Pineapple Express

Saturday, December 11, 2010
2:18 P.M.

Wait a minute...

There we go. :)

The word is out that we will likely see some of the biggest flooding since January 2009 on some rivers, and January 2009 was a record-breaking event for the Snoqualmie @ Carnation and saw major flooding on many other rivers. Some rivers are certain to flood, like the Skokomish, and others will probably flood also, like the Snoqualmie. Thankfully, the Green River doesn't look like it will quite reach flood stage, although with qpf (precipitation amount) forecasts going upwards over the last few model runs, we will have to keep a close eye on the situation there. 

We have a lot to talk about, and I'm sorry I couldn't get to it earlier. I was studying for the ACT, which I took this morning. Anyways, the leading edge of the warm front from this system is over us now and is bringing light to moderate rain to many areas, which will only increase in intensity as the weekend progresses. The radar below shows that a lot of rain has already spread over the area, and it will only get heavier as time goes on.

We also have some snow issues to deal with today. While this will mainly be a rain event, there is some cold air trapped in Eastern Washington and that cold air is causing snow from the passes eastward. Rocky Canyon, east of Cle Elum, is getting moderate snow right now.

Snoqualmie Pass is getting dumped on as well.

This cold air will work its way out as milder air from Hawaii starts to invade the area. Until then, expect heavy snows in and east of the Cascade passes. We could also encounter some sleet and freezing rain as well during the transition.

But the real story here will be the rain. Freezing levels will shoot up all the way to 8,000 feet with this storm, which means pretty much everything falling in the mountains will be rain, save the volcanoes and highest peaks. The new models showed generally 2-3 inches of rain in most parts of the lowlands in the 24 hour period between 4 P.M. tonight and 4 P.M. Sunday. You can see some areas of white in the graphic below, and those areas illustrate where there is the potential for over 10 inches of rain in 24 hours. 

This is a serious flooding event, but it isn't too out of the ordinary. We usually get a storm like this every year or so, and this one won't be as serious as the ones of November 2006 and December 2007, which caused catastrophic flooding on many rivers. However, I do expect major flooding on many rivers flowing off of the Cascades and Olympics for several reasons. The forecast models have been trending wetter and commonly underestimate precipitation amounts in Pineapple Express events, which is why I feel like we are going to get more serious flooding than the National Weather Service's hydrological center is predicting. 

Looking at the forecast model above, which is the 12z GFS, you can see an intense rain shadow northeast of the Olympics. While some areas of the Olympics will likely see a foot of rain in this period, some places 60 miles away might get only .01 inches. That is 1200 times less rain! Just goes to show how pronounced the Olympic rainshadow can be. So if you live north of Seattle, you'll start to feel the effects of the rainshadow, and if you live by Port Townsend, you'll probably be wondering what all this fuss about flooding is about. Because the winds in the middle atmosphere are traditionally very strong with Pineapple Expresses, they drop a ton of rain over the mountains via orographic enhancement, and then sink rapidly on the leeward sides, preventing much more precipitation from falling (at least until they hit the Cascades again).

We will have to be careful of urban flooding as well. While we won't have any convective downpours like we did that one morning last week, we will see a lot of rain in a fairly short period of time, and with all the leaves down, expect storm drains to get clogged up and large puddles to result.

Latest river forecasts can be found HERE: http://water.weather.gov/ahps2/forecasts.php?wfo=sew&view=1,1,1,1,1,1,1,1&toggles=10,7,8,2,9,15,6

Stay dry, and stay safe :)
Charlie

Flooding?

Tuesday, December 7, 2010
5:44 P.M.

I know... I know... I haven't updated it in a while. Same story as always... I've been extremely busy. I thought senior year was supposed to be a breeze! Not with my class schedule... we will see if all my hard work pays off and I get into college. Hopefully I can at least get in somewhere.

Alas, this will be a short post, as there is more work to do in the homework department. However, I've been watching the models very intently for the past few days and they have been EXTREMELY consistent in showing a Pineapple Express event. The nature of the event, however, has been anything but consistent. Model runs have ranged from bringing all the rain to Oregon to a bulls-eye over Seattle to bringing the majority over Vancouver Island. They seem to be trending further northward. Things could change, and it will be wet around here, but I don't expect major river flooding issues in the Central and South Cascades. This means that the Green River will probably escape the flood threat, which is good news. The Olympics, North Cascades, and southern mountain ranges of British Columbia (Vancouver Island and the mainland) look to get a lot of rain, but we just aren't sure how much. The latest model runs don't stall the front as much either, which means more areas will get rain but less overall than if it stayed over one specific area.

In the meantime and in between time, it's raining heavily over the lowlands right now, and we could see an inch out of this storm system over the next couple days. The "Pineapple Express" over the weekend has the potential to give us even more significant rains, but the model runs as of now don't show a ton of rain for Seattle. It is a situation that bears watching.

And no snow in the foreseeable future.
Thanks for reading. :-)

Charlie

0:09 minutes

A Little Bit Of Light Snow This Morning, Then Changing To Rain

Thursday, November 25, 2010
8:59 A.M.

Hey ya'll, so we are seeing a little bit of light snow this morning. It's not that big of a deal because it is going to change to rain later in the afternoon and it will melt. I suspect some roads will still be slushy (especially sidestreets) but as time goes on we will warm up enough that that slush won't last too long either. I've gotten less than an inch so far at my house, and most other places will receive the same amount of snow before it changes to rain, save the hills and up north in Bellingham where you could see up to 2 and 3 inches respectively. A WINTER WEATHER ADVISORY is in place for all of Western Washington except the Cascades, where a WINTER STORM WARNING is in place for a foot of snow.

Other than that, there isn't too much to talk about. The DOT handled the roads nicely with salt, which of course, I didn't really like, but it was ok because I got school off anyways. Salt kills engines and the environment, but it works. Still, I like seeing the arterials white with snow. I went skiing down some back in 2008. THAT was fun.

We will be gradually warming up to "balmy" temperatures in the mid 40s with showers most of the time, except some drying during the weekend. No big storms look to be headed our way.

However, there could be another arctic outbreak on the horizon. It looks very unlikely at this point, but some models have been showing some arctic air spilling down. Right now, it is much too far to our east. We will see if we get some more Fraser River outflow. This would be in approximately one week. I'll keep you posted. LAWES level 1.

But it heads off much further east later. Still, an impressive arctic high!

Of course, the mountains are looking good for snow. Here's the Alpental base...

And here's Snoqualmie Pass...

So the lowlands are done with snow for a while, but the mountains will get some, and there is a possibility, albeit slim, that we could return to colder weather next week. Have a great day and give thanks for the snow we did have. :)

0:26 minutes

Visibility

Ok, visibility kinda sucks, at least right now. It may change. I'm not sure why. Maybe because the snow is giving off some moisture, maybe because there is more particulate matter. But it will get better throughout the day today. I might talk with Scott Sistek more about this. For those of you who don't know Scott, he's the man. Find him on "Scott Sistek Weather" on facebook. In addition to his insights, me and a bunch of weather nerds always post stuff on his wall. It's a really cool community, and those who are excited about weather should check it out.

Midnight Update

Monday, November 22, 2010
11:50 P.M.

So the snow has now largely come to an end. Don't be surprised if you see a flurry, but I doubt you will see any additional accumulation.

Generally, I've been hearing of about 5 inches of snow in the Seattle area. I have 5 inches at least. Very, VERY cool stuff. I'm pretty darn happy right now. And the mountains are getting tons too.

This has been pretty crazy. This much snow this early. Let's hope that it is a precursor of things to come. I think I already said this too, but Barrow, Alaska was warmer than Seattle today.

The big stories now are going to be cold and wind. First, let's look at some temperatures. This model below shows the 7:00 A.M. (generally coldest part of morning this time of year) temperatures for Tuesday morning. Seattle will likely get down to 20 degrees or so. Even areas near the water will still be below freezing.

By the way, tomorrow will feature SPECTACULAR visibility. The atmosphere is very dry, there is little air pollution, and it will be completely sunny. There will be a marked difference. When you don't have humidity or particulate matter clogging up the atmosphere, you can see a lot further. That is why deserts (except when they have dust storms) are often very good for viewing stars - very low humidities.

The day after tomorrow (haha) will be even colder. Here is the same chart 21 hours later (the morning low will occur earlier because the sun will be out).

Even colder for Seattle! You can already see warming off the coast - that is part of the high pressure that gave Barrow a high of 34 today coming in. Yeah, it's that big of a high pressure ridge. But in Seattle, lows will get into the mid teens. Outlying locations could get to 0 degrees.

This graphic shows how dry the air mass is by measuring the RELATIVE HUMIDITY of the atmosphere. It is for mid-morning tomorrow. See that orange around us? It means we have a relative humidity of 25 %. That is extraordinarily dry. And colder air masses hold less moisture (90 degrees 100% relative humidity is much more humid than 50 degrees 100% rh) so a subfreezing air mass with a relative humidity of 25 % is extremely dry.

Haven't shown the relative humidity graphic before. It's a cool one. :)

Now - winds! The saga never ends. The winds are blowing like crazy up north right now, as this graphic shows. This shows what was forecasted for 10 P.M., so it is actually an old graphic, but that is when the winds peaked and this is how fast they were. Note - these are SUSTAINED winds. Multiply by 1.5 to get gusts (approximation).

You can see a very localized, but intense, area of winds up north.

These winds will weaken, but winds will spread throughout Puget Sound Tuesday as this graphic indicates.

It will be cold and windy, especially in the sound. This graphic doesn't show Seattle getting real strong winds, but all you need to do is shift the gradient a little, so I would still be on the lookout for some gusts tomorrow. Places over water, however, will take the main beating. These winds, however, will be nowhere near as strong as the ones being witnessed right now over the San Juans. A high wind warning is in effect for those areas right now. Winds over most of the sound look to be below advisory level for most of the day (except in that dark band of blue and green).

One last graphic - the 1000-500mb level thickness model is regarded as "the" model to determine the true strength of an arctic outbreak. Simply put, it measures the temperature of the lower atmosphere. More complexly put, it measures the distance in decameters from the 1000mb air pressure level to the 500mb air pressure level in the atmosphere and calculates how cold it is based on the distance, with a lower distance being colder (cold air is denser, takes up less space) and a higher distance being higher. Heat waves generally have a value of above 580 decameters in Washington. You have to start thinking about snow when it gets to 522 dam (dam=decameters). Right now, it is like 507 dam. That is extremely low.

This is for tonight at 1 P.M. As I write this now it is 12:51 A.M. Yeah this has so far taken me one hour, but I enjoy doing it. I was watching the Bourne Trilogy but decided I'd rather write an update.
You can see that there is clearly a lot of arctic air in Western Washington. If this was in December or January, I would seriously be concerned about highs getting out of the teens. No joke. They might reach twenty. But we are gonna get an arctic blast that has not been diluted too much.

Wow! The models actually showed this 16 days ago. Not this exact scenario, but this idea. Pretty crazy. Then they shifted to highs in the 40s, believe it or not. There is not a lot of data over the arctic, so models commonly have problems with these situations. Given that it is a La Nina year, I expect that we will see more arctic outbreaks. This is definitely a good way to start. :).

To wrap it up - cold tomorrow and FRIGID Wednesday morning, before moderating while remaining mostly dry through Wednesday. A more active, typical storm track will return after a system affects us on Friday.

1 hour, 12 minutes (now I'm going to post how long I've worked on these. Hopefully someday I can count them all up. :)
Charlie

Yes, I failed!!!

Monday, November 22, 2010
6:22 P.M.

WOOHOO!!! I can't believe this is happening. Winter storm warning and 2 inches of snow and counting! The models predicted zip. Cliff Mass predicted zip. Scott Sistek predicted pretty much nil. I gave you a 5% chance of snow. The National Weather Service was just ignoring the models and going on their own judgment, which I thought was silly because one of the models was very very consistent (the GFS) in showing no precipitation whatsoever for us. Well, they were definitely wrong. And we have gotten very cold. I just got a report from Nicholas Efthimiadis of an air temperature of 23 degrees with three inches of snow. The extremely cold weather and extreme warm weather in Alaska due to a huge ridge over the central Pacific that is making all this possible in the first place has given us something I thought I would never see in my lifetime. Barrow, Alaska, the northernmost point in the U.S. and well within the arctic circle (they are seeing no daylight right now) is warmer than us. That is truly phenomenal. They are 25 right now. We had a high of 32, they had a high of 34. I don't know what else to say but that I'm completely blown away. I can't ever recall a time of that happening.

So what is happening tonight?
Right now we have periods of light snow that I expect will intensify in the next hour or so. Now, most weather guys would tell you that and just end it there. But I'm not content. This blog is about explaining WHY some things happen, so that you can leave each read with a better understanding of Pacific Northwest weather and have an appreciation for it.

 As you can see, there are some snow showers around the area. There is not much upper-level motion in the atmosphere right now - that is: the precipitation isn't really moving - but as you can see, there is a fairly wide swath of snow to our north, with some embedded heavier rates (like the yellows you see). Now, this isn't moving much, but it is moving to the south very very slowly. Snow has already increased around my area, however. There is a good chance that this feature could give us quite a bit of snow, especially it stalls over us and intensifies. By quite a bit of snow, I mean above 4 inches. That is a possibility, particularly if this feature has a convective element to it. A convective element is pretty much instability in the atmosphere.

Alright, so we got that out of the way. What will happen tonight?
The models have been pretty consistent with wind. I haven't seen the new GFS come out, so this is the model from this morning, but I suspect that the forecast will now be for even higher winds because the low that did come in was MUCH stronger than forecast. I'm sure you were able to figure that one out. this will create tighter pressure gradients. I would not, under any circumstances, be surprised to see a 80 mph gust up by Bellingham. Even Seattlites will encounter brisk windchills in the teens with gusts up to 40 miles per hour, or perhaps even 50 miles per hour in spots. I will look again at the new models when they come out tonight and update this forecast. But anyways, here's a graphic for 10 P.M. tonight, showing some rather high wind gusts from the northeast, especially by Bellingham. Windchills there will be below 0 in most spots. Cold temperatures combined with losing power present a danger, so if you know people who lose power or do lose power, do things to keep warm. Start a fire. Get a blanket. Use a generator if you have one, but do NOT under any circumstances put the generator in your house. This causes asphyxiation and you will die.

The San Juans in particular will get pounded. There may be some freezing spray, so it is a very bad idea to be out there. Storm force winds and frigid temperatures. Don't be out there tonight.

Photo disclaimer - I LOVE Andy Wappler. This is just a photo one of my friends made satirizing all weathermen who claim there will be snow, then students don't do their hw, and then they get bad grades. I do NOT think any weatherman is a douchebag. But if I had a final and I was lazy and the snow forecast didn't consolidate, I'd be kinda tempted to call the weatherman a douchebag. If I mess up and your grades are affected, there is an official 24 hour window from the beginning of the school day to the next where you may call me a "Douchebag."

Of course, the issue of people hating weathermen is going to come up, although I think it applies more for when snow IS forecasted and doesn't come true. It's easy to say "why didn't we think this" in retrospect, but the fact is, weather is a prediction. You never for sure know what is going to happen until it already is happening. So the best we can do from events like this is learn from them, and if we see a similar situation evolving in the models, take it with a grain of salt, because our models are not perfect. There lies the main difference in forecasting between the two powerhouses of Pacific Northwest weather prediction, the National Weather Service's chief forecaster Brad Coleman and UW's atmospheric sciences professor extraordinaire Cliff Mass. Cliff goes with the models more, while Brad has more human input. I'm generally with Cliff, although I do definitely take historical context, satellite, radar, and other stuff into context. He does too. Two years ago, the models were forecasting snow, but it was a really chancy situation and nobody believed it would happen. NWS said slushy accumulation of an inch possible. I said we could have 4 inches. We got 6. It's hard though, so cut us some slack.

The snow is increasing and will continue to increase. Tomorrow will be VERY cold. I need to eat dinner with my family, but I will look to make another update later tonight. Recap - up to 4 more inches of snow is expected tonight as this feature moves down from the north, keep an eye out for convection, and wear a coat. And PHOTOGRAPHERS!!! Take some shots tomorrow, it will likely be the clearest day of the entire year. Extremely low humidities, and the mountains will have snow. Parents are getting anxious. Ciao. :)
Your local weatherman,
Charlie Phillips

FOR THOSE INTERESTED IN POSTING SNOW TOTALS - Post them as a comment. Hardly anybody comments on my blog. I'd like to change that!!!

Snow chances today and tomorrow

Sunday, November 21, 2010
12:28 P.M.

Hey guys. Some of you saw some snow flurries this morning. Some of you did not. It depends on where you live and your elevation. I say some flurries but no accumulation. It was pretty though.

Let's discuss snow probabilities. I read Cliff Mass' blog the other night and he said "forget about snow in Seattle, it's going to Oregon." He's probably right. The models which are usually more accurate (the Euro and GFS) have been showing this scenario, and they have been showing it consistently. The Canadian model has also been showing it as well. The latest 12z run of the UW 4 km GFS, our region's best model, shows absolutely no accumulating snow for Seattle (except traces).

Notice how there is a good amount of snow south of Olympia. But we don't get any.
However, the NAM model does paint a better picture for snow enthusiasts and school procrastinators around the region. It shows a bit of snow later today, maybe accumulating to an inch in spots, although most places will see no accumulation. The bigger story is the Puget Sound Convergence Zone that it is forecasting for Monday. The timing would be weird - it is forecast to occur during the morning of the school day. But it might deliver a few solid inches of snow to the area if it does verify. However, the NAM has not been consistent, and the GFS is the preferred model here. Sorry guys.

However, as you can see, through 4 P.M. Monday, it shows 1-3 inches of snow over Seattle. Your biggest tool here will be the radar. Keep your eyes peeled to the radar because we may not know what is actually going to happen until it actually is.

I need to do more hw, but I'll update this more if needed. However, that's most of it right there. Perhaps some snow, but not likely. Any snow we do have is likely to be focused on South Seattle with points north and south getting some as well.

However, the models aren't accounting for the large wave of hope providing HOPE on some of the clouds here as well as a possible arctic front of BELIEVE sweeping down from the north. Thanks will. :)

Have a nice day,
Charlie

UPDATE - 1:09 P.M. The National Weather Service now has a WINTER WEATHER ADVISORY for all of Western Washington. 1-3 inches expected Monday, according to them, and up to two inches in isolated spots tonight. I'm not sure if I believe it yet though...

The Truth About Snow

November 16, 2010
8:53 P.M.

Alright ladies and gents, it's time to tell you the TRUTH about snow in the upcoming days. There have been a lot of rumors flying around. I don't know if I've ever told you, but I hate rumors. But not weather rumors! Weather rumors create an exciting atmosphere (there's a knee-slapper right there). However, I don't want you guys to get your hopes up and then have a massive let down, because snow is a chance at best. However, I am becoming more optimistic about it after seeing the latest model runs.

Before, models were showing most of the cold air being shunted to our east, which is what usually happens. The location of the arctic high has to be just perfect to direct significant arctic outflow into our area. Why? Because we have not one, but two major mountain ranges ready to funnel air to our east. The air has to be just far west enough to avoid these mountain ranges, but if it is too far to the west, it will moderate over the ocean. It's one of those classic situations in which even small changes in the models could have huge changes in the forecasts.

Let's first discuss the most likely scenario, which, at this point, is a blend between the European (ECMWF - European Centre for Medium-Range Weather Forecasts, if you wanna impress your friends) and American models (mainly the GFS - Global Forcast System) as well as just common sense with what usually happens with predicted snow events (i.e. - one thing can completely screw it up). Most t.v. forecasting stations are predicting dry-ish conditions once the cold air sets in, which is correct, and they aren't going all-out on the intensity of the cold air, which is what I am also forecasting.

Let's break it down. Tomorrow, we will be wet and rainy. The mountains, however, will be very snowy. I have a feeling that the models are underdoing the precipitation for Snoqualmie Pass. They are calling for around 8 inches of snow there, but I'm expecting a foot. The orographics are very favorable for snow in the passes from the looks of it. The volcanoes will get pounded. Don't be surprised if Paradise and Mt. Baker pick up 2-3 feet of snow from this storm. The below model shows the thickness of the atmosphere near the surface to the 500 millibar level (level in the atmosphere where the air pressure is 500 mb) and is measured in decameters. Don't ask me why it is measured in decameters, it just is. But anyways, the brighter reds and yellows mean that the temperature in the atmosphere is higher because the number of decameters it takes to cross 500 mb in the atmosphere is greater, meaning the air is less dense (warm air is less dense than cold air). The blues, purple, and whites mean colder air. Once you get to around the 522 decameter level in our area, it's time to start thinking about snow.

This image shows the low off Vancouver Island, and you can tell there is a front over us because of the large change in thickness (a front divides different air masses). This forecast is for tomorrow Wednesday at 1 P.M. PST. Now, watch what happens.

The low has weakened and moved to the southeast, right off of our coast. This is a crucial detail in the forecast. Dropping this low southward now gives us winds from the northeast. And there is a lot of purple to our northeast.

I don't think that that low is going to be strong enough to pull in a whole bunch of arctic air. However, a reinforcing shot of arctic air might hit us early next week. The models are showing different things, but the GFS model (shown) has been consistent in showing this solution. Unfortunately, we also run out of moisture.

So the question remains: will we get snow?

There is a chance we might get a few isolated snow showers over the weekend, but I don't think they will be heavy and widespread enough to close school. However, if a convergence zone forms over Seattle at night and dumps a whole bunch of snow, we may have a shot at a day off. One of the models was showing highs in the low 20s for Seattle and snow totals of 8-18 inches for us. I doubt that is going to happen, I'm just using it to illustrate how tough of a forecast this is. I think our best shot at snow is either with an arctic front with the reinforcing shot of cold air (and then it would freeze on the roads as the arctic air sets in) or an overunning event with a system off the Pacific "overunning" the cold air, producing snow. That is a very real possibility. But so many things could change. A couple things are for certain - it will get colder - the mountains will see snow - and the days will keep getting shorter until the winter solstice.

I HIGHLY recommend friending Scott Sistek and Steve Pool on facebook. Type in "Scott Sistek weather" and "Steve Pool komotv" and they will come up. They provide discussions, but their walls are also discussion places for me and other weather nuts to discuss what we see in the models. It's a very fun place!

On the windstorm last night - it was very unique, I'll talk about it some other time.

Pray for snow please. :)

Charlie

Charlie Phillips' LAWES (Likelihood of an Arctic Weather Episode with Snow) scale

November 11, 2010
9:09 P.M.

Making an acronym that sounds like an actual word (aka: not MOFACASOSWWWW - Major Outbreak of  Frigrid Air, Copious Amounts of Snow or Other Severe Winter Weather in Western Washington) actually took me a really long time. And I'm sorry I haven't been updating this, the weather has been boring and I've been absolutely swamped with schoolwork. However, there could be some interesting weather on the horizon and the quarter just ended, meaning that although I still have a ton of college apps to do my schedule has lightened up slightly.

So, lets go through this scale.
LAWES level 0: You are on a planet that has the ingredients necessary for snow
LAWES level 1: Models are showing a chance of snow beyond a week out, 0-20% chance of snow
LAWES level 2: Models are showing a chance of snow within a week, 20-40% chance of snow
LAWES level 3: Models are all showing a scenario that would easily produce snow within a couple days, 40-60% chance of snow
LAWES level 4: Places around the area are already getting snow AND snow is forecasted for Seattle, 60-99 % chance of snow
LAWES level 5: Snow is occurring, 100% chance of snow (derp)


Now, notice how there are no measurements for how strong a Seattle snowstorm could be. But have no fear! That's what suffixes are for.
Ending in:
.1 - 0-2 inches of snow
.2 - 2-4 inches of snow
.3 - 4-6 inches of snow
.4 - 6-8 inches of snow
.5 - over 8 inches of snow
.6 - board the next plane to Panama

So a level 5.6 (below) would mean that snow is occuring and that you should leave the country if possible. Photo props to Alex Jonlin. That storm brought 21.5 inches of snow to Seattle in 24 hours.

Now that that is out of the way, let's discuss the weather forecast. This week is boring. If you want to know about this week, go to a different blog. However, things get rather (pause) "interesting" (sly smile and rubs his hands together) next week. The atmosphere will shift into a classic La Nina pattern, with a HUGE ridge over the eastern Pacific and then a trough on the eastern coast of it (us), directing arctic air down from Canada into the western U.S. Now, there are a lot of questions remaining about this scenario - how cold will the air mass be? How far west will it go? Will it be deep enough to cross the mountains into Western Washington? Seeing as the models have been inconsistent, I am giving this a LAWES advisory level 1 (no specific sublevel), which means there is a 0-20 percent chance of snow occuring in the lowlands. I will keep you posted on if things change. One thing is for certain though. The rest of the country will get extremely cold. We just don't know if the arctic high will go west enough for us to get some of the cold air.

This model shows the weather forecast for a whopping 2 weeks out. That is way too far out to look at individual storms. However, you can look at trends. Here, the models show an arctic high diving into Western Washington and giving us cold air. That's what all this fuss about snow is. We will see if it comes true!
Have a nice night!
Charlie

P.S. The Garfield News Network needs another weatherman! If you are interested in the position, let me know, and we will see if you can get the spot!

Putting that Big Midwest Storm in Perspective

October 27, 2010
1:59 P.M.

Look at that storm!!!

Now, many of you may have heard about the huge storm in the Midwest. There has been a lot of talk about it being the strongest extratropical storm on record on the contiguous 48 states. The media generally says it is. However, many of the local weather guys around here say no. Who should you believe? Well, you should believe me, and both sides have valid points.


This storm officially has the lowest pressure ever recorded by an extratropical cyclone on the contiguous 48 states. The mercury bottomed out at 28.20" (954.9 millibars) in Bigfork, Minnesota yesterday at around 5:13 CDT. This is an official, all time record. Now, note that I respect Cliff Mass very much and regard him as a GOD, but I think he is mistaken when he says that we have had the deepest storms. We have had some very deep storms - the most recent example being a storm from December 12, 1995.  According to Wolf Read that storm probably bottomed out at 953 millibars, (see my Storm King website link - he has put together a fantastic website of historical Pacific Northwest) which is deeper than this storm, but by the time it reached land, it was above 955, and I think the lowest actual measured pressure was like 958 mb or something. So that storm is not the deepest storm to hit the continental U.S. There may be a storm back in January 1880 (which has been nicknamed "The Storm King" itself) that may have been deeper, but there is not a real official reading. So the record belongs to Bigfork. What a funny name for a town.


BUT... our windstorms are stronger than theirs by far. Why? Because our storms are more compact and have  stronger pressure gradients. Look how big the storm is in that satellite photo. The winds cover a huge area. However, since they cover such a big area, they are also less extreme. The pressure gradients drive the winds, and if the storm is bigger and the pressure gradients are more relaxed, the winds are not going to be as strong. There was an 81 mile-per-hour gust and it made national headlines. I think that's pathetic, personally. That really is not that fast. The coast sees gusts like that every winter, and even Puget Sound gets them sometimes. 


A great example to show how our storms are more compact than the ones over the rest of the nation is our "Intense Cyclone of November 3, 1958." 

This is from Wolf Read's website. This storm was only 985 mb, yet it produced a 161 mph gust. Contrast that to a 955 mb storm that produced a 81 mph gust. This clearly shows the difference in wind velocity between the two storms. Our wind velocity is higher because this cyclone was much more compact.


But no windstorm can even approach the Columbus Day Storm in terms of wind speeds. 

Gusts of 116 in downtown Portland, 127 in Corvallis, 160 at the Naselle Radar site (it commonly gets really windy there), 170 in the Tillamook Forest, 150 SUSTAINED at Cape Blanco with gusts to 179, or they may have been as high as 195, as one of my many weather books estimates. Renton got to 100. Newport got to 138. The list just goes on and on. THIS is the "perfect storm." Not that 1991 weak thingy. The "Perfect Storm" of 1991 had a peak gust of 85, and that was at a coastal station. There is a possible 110 mile-per-hour difference in peak wind gusts. So much for the "Perfect Storm!" When you add that on to the fact that the Pacific Northwest has tons of huge, shallow rooted trees to blow down and the Northeast has a lot less, you wonder where that storm got that name in the first place. Here are some Columbus Day photographs to give you an idea of the damage. Everything is from Wolf Read.

There is one thing that those easterners do have on us though in the "who has more gnarly extratropical cyclones" and that is severe thunderstorms. Their cyclones produce severe thunderstorms. This last one produced a little over 20 tornadoes, and although I don't think any of these tornadoes were huge, there was one storm that produced a huge tornado outbreak. April 3, 1974 was a date that will live in infamy as the largest tornado outbreak ever recorded. And these tornadoes were strong. 315 people died and over 5,000 were injured. 


Take a look at this tornado. It hit Xenia, Ohio as an F5 with estimated 300 mph winds and completely decimated the town.

So, the most damaging event was not the Columbus Day Storm or the one that we just saw over the Midwest.  It was the "Super Outbreak" of 1974! A great website to learn more about this outbreak is http://www.april31974.com/. When people talk about the strength of extra-tropical cyclones, they are generally talking about wind speed that is associated with the pressure gradients directly. In that case, the Columbus Day Storm outshines everything else by several orders of magnitude. But the Super Outbreak was a horrifically powerful weather event in a different way, and that's why I am calling it the most destructive extratropical storm the United States has seen in the last 110 years.


Oh yeah... a weather forecast.
We could see flooding next week. Stay tuned...
Charlie Phillips, over and out.

And... Storm Season is Underway!

October 24, 2010
10:21 P.M.

I hope you guys like the new blogger template by the way. I don't care for it too much but it is a newer update so I can do more stuff, like put bigger pictures on it and stuff. I'm a fan of bigger pictures. 'merica, right? Bigger is better.

However, if you happened to be kayaking off the Washington Coast this weekend, you would probably disagree with me. The huge waves that we've been advertising for a while are hitting the beaches. These waves are not just large, they are gigantic. The average significant wave height is expected to be 33.5 feet off the coast tonight and tomorrow. As far as I can remember, there has only been one event with bigger waves, and that was when 44-foot average waves were recorded with individual heights as high as 70 feet during the December 2007 Great Coastal Gale (crazy windy on coast, not windy here, flooding everywhere). There's still a 10 foot difference in the wave heights though, which just serves to show how intense the 2007 storm was.

Snoqualmie Pass is getting a rain-snow mix, and Stevens Pass is all snow. I gotta go to bed (school tomorrow!) but we may have some more interesting weather at the end of the week. I'll keep you posted.
Charlie :)

Big Coastal Storm on the Way!

October 23, 2010
2:01 P.M.

Many of you guys probably noticed that I didn't update the blog the last couple days. I had a ton of homework. I'm not taking the easy way out of high school, I'm taking some really advanced classes so I can get into some good colleges. Then it will be a matter of seeing how much money they give me (I don't care what college you go to, 50,000 dollars a year is a scam). But yes, we have a major storm slated for later tonight that will give the coast some huge waves, as well as giving some wind inland and some rain both in the mountains and lowlands. The Cascades could see their first significant snowfall of the season with this storm as well. First, though, let's look at the water vapor imagery to give you an idea of what is really the driving force behind this storm.

You can see the beginnings of the low-pressure system starting to form. There is a bent-back occlusion and a strong "dry slot" to the south of the center of the low. What is even more impressive to me, however, is the visible jet stream in the water vapor imagery all across the Pacific. You want to know what zonal flow is? THAT, my friends, is zonal flow. The jet stream is extremely powerful and centered right across the Pacific, and it has tapped into a ton of moisture (most of it from that big supertyphoon, Megi, which actually got down to 895 mb with 180 mph sustained winds!). Very, very impressive water vapor imagery from our satellites.

But what's the actual forecast? This graphic should sum it up.



Waves! Look at those wave heights! 40 foot waves could batter the central Washington coast! That is just astounding. I've seen higher waves (December 2007 - average recorded height at a buoy by the Columbia was 44 foot waves with individual ones as high as 70 feet before the buoy became unmoored) but these are still extraordinary wave heights. I'm trying to convince my mom to take me to La Push tomorrow to witness these waves but she says absolutely not.

Some of the coastal areas have storm warnings, Willapa Bay southward has a high-wind warning (coast only), the Skokomish River might get flooded, and the mountains even have winter storm watches! As I've been advertising for a while, the mountains above 4000 feet could get a real dose of snow. I would not be surprised if they got a foot from the highly unstable air that will be filtering in Sunday night after this big event is over. The air temperatures in the upper atmosphere will be cool enough to support snow at the higher passes. I think Snoqualmie Pass will see a rain-snow mix, but would happily be proven wrong. For those of you who ski at Alpental, the upper mountain should get a good dumping! Because of the snow, there will be no flooding concerns on the Cascades.

Sit back and enjoy the show folks! What a way to kick off the storm season!

Storm Details Uncertain

October 20, 2010
4:34 P.M.

The details on the storms this weekend are still very, very murky. The American models, the GFS and the NAM, have been forecasting a large low pressure system to bottom out in the Gulf of Alaska at around 950 millibars, sending a strong front right into our area. This is a very deep low, but, surprisingly, these type of events are not all that uncommon where sub-950 millibar lows intensify until they kind of stall in the Gulf of Alaska. Here is a picture of the mm5-GFS model for 5 P.M. Saturday.



It is pretty similar to what we have been seeing all along. The coast has the best chance at getting high winds with this storm, and I wouldn't be surprised to see a stray 70 mile per hour gust, especially at Tattoosh Island. Gusts inland will be in the 30-40 mile per hour range. 

Now, let's look at the Canadian model, which is showing a scenario that would give us some wind. This model takes that one big storms and splits it into two smaller storms, but they come right at us. The same sounds true with the Euro, although since I'm not in the NWS I don't really have good access to that model. Here is the 00UTC Monday map (around 4 P.M. local time I think)

As you can see there is a powerful 965 mb cyclone slamming right into us. That would give us high winds. The latest GFS also *kind of* follows this, though the storm is further north and it kind of fizzles out before hitting us, stll giving us lots of rain and wind but not windstorm-type winds. One thing is for sure - the Cascades above 4000 feet will get a LOT of snow from this storm, and I think Snoqualmie Pass will end up getting some too.

The NWS guys will be busy over the next couple days. Come to think of it, so will I. :)

It's Gonna Get Bad, but Where and How Stormy?

October 19, 2010
5:24 P.M.

Well, the models have been all over the place over the past few runs with what they are showing, and I know exactly why. First, the jet stream is very strong, and although models are good at picking up this pattern, they have a hard time pinning down what storms will affect which areas at which time. Often, when the models are as inconsistent as they are now, meteorologists will "broadbrush" the forecast, meaning they say it will be wet but don't give any specific details. Usually it is reserved for longer range forecasts outside of a week or so, and this storm is expected to come in Saturday night. However, due to the inconsistencies in the models, the NWS guys are just saying it is gonna be wet and giving more details later. Another reason is that the NWS confirmed that tropical moisture IS going to be entrained in this system (I called it!) from supertyphoon Megi, which once had a central pressure of 895 millibars and sustained winds of 180 miles per hour! Obviously, that powerful of a storm is going to offer some very deep tropical moisture, and just how much of it gets entrained in the jet stream is going to make a huge difference on what kind of a storm we will see. Our models generally have issues pinning down details when tropical moisture is involved.

The trend over the last few model runs has been to put the heaviest precipitation in California. We will see if this comes true. Washington will still get a good soaking though, and there could be very strong winds out on the coast and at least blustery winds inland. Here's the 24 hour precip ending at 5 P.M. Sunday. Lots of 10+ inch totals in the mountains of Northern California.

Beyond, models still show active stuff, but I'm not going to give any details because they will change. It will, however, be wet and windy. There's a broadbrush forecast!

Charlie

Pacific Storm Train Update

October 18, 2010
4:04 P.M.

So, that strong surface low that looked like it was going to plow right into Western Washington has gone away, but the models are still showing an active pattern with a lot of rain possible. Here are some shots from this morning's MM5-GFS run (12 UTC cycle).

You can see the beginnings of a storm on the left (where all the precipitation is). I don't know if this moisture is fed from tropical sources but it looks like it is at the very least subtropical. Of course, it is being driven by a very strong jet stream directly westward and that is what will allow it to strengthen.

The next image shows it in the process of what is called "explosive cyclogenesis," or as seasoned meteorologists around here say, "bombing." This basically means that the central pressure of the low is dropping rapidly and the system is quickly increasing in intensity.

As you can see, the occluded front is well-formed, there is a very strong and moist warm front out ahead of
the system, and there is a long cold front trailing behind it. And look where the bulk of the moisture goes!

... you guessed it - right into Western Washington. In fact, from 5 P.M. Saturday to 5 P.M. Sunday, some places could see 2-5 inches of rain, perhaps up to 8 inches in the wettest spots, as the red in the graphic below shows.

Seattle may be rain-shadowed though, especially north Seattle, and might not see much at all. It is VERY important to point that out - weather forecasters often do not communicate things like rain shadows very well to the public, so when Seattle ends up getting very little rain they are not surprised while the rest of the city just thinks the weather forecasters got it wrong... again. That's something all weather forecasters need to do. However, from this graphic, it looks like Seattle will still get a good amount of rain, but you can see a sizable shadow with a bullseye around the Kingston area.

Remember, this is only one possible scenario. Other models are not showing this situation quite yet, so we might end up with a fairly dry day (though we would probably still see some rain). But it is never fun to analyze those models. I guess we will just have to wait and see how everything unfolds! It's that time of year...
Charlie

Pacific Storm Train Ramping Up?

October 17, 2010

Hey everybody, thanks for continuing to read my blog, it means a lot. I know I've not been writing for a while, that generally means I just have a bunch of homework to do, as was the case this past week. I still have a ton of homework to do, but I thought I'd write a little update on what we can expect weather-wise the coming week and beyond. Just remember that when I'm not writing, it's because I'm busy, not because I've forgotten about the blog or suddenly lost interest in weather. You just have to straighten out your priorities, you know?

This is an image of the jetstream over our area (more specifically, the winds at the 300 millibar level in the atmosphere). As you can see, it is aimed right at us, and when we have the jet stream aimed right at us, the "Pacific Storm Train" occurs. If you remember either January or November 2006, it is easy to see why they have given it this name. Once the "door is open" (that is, there is no blocking ridge of high pressure and the jet stream is pointed directly at us), storm after storm after storm can hit the Pacific Northwest. These storms are usually strong and progressive, which means that they can bring a lot of wind, rain, and snow for several hours, then they will pass, only to have another storm arrive several hours later. Flooding is generally not a huge issue with this type of zonal flow because snow levels are lower than if the jet stream had a more southerly component and the periods of rain are usually shorter with more breaks between them. However, we can still get flooding rains, don't misinterpret what I am saying. They are just more likely in a setup that is not as fast or progressive and where the jet stream dips down towards Hawaii and is then shunted in our direction by a ridge of high pressure to our south. Pineapple Express (flooding) events are often triggered by a pattern in the tropics called the Madden-Julian Oscillation, but I will talk about that at a different time.

In the meantime, take a look at some of the forecast images from the GFS model that show a potential windstorm about a week from now and a very strong jet. Normally I would just discount this individual windstorm and say we are just going to be in an active pattern, but the models have been very consistent with this individual storm. And yes, I finally found out how to make everything clickable, so now you can actually get a good idea of what is going on because you will be able to see the pictures at the right size! Thanks for looking and savor your sunshine while it lasts folks because it looks like we are going to get stormy.

Charlie

A Little Bit of Housekeeping and a child abduction emergency

Hey Everybody! I just put pretty much all the stuff I ever posted on my facebook blog which I am no longer using (http://www.facebook.com/group.php?gid=33875355514)
on to this website. I put them in posts organized by months and it goes back to April 2008. So yeah, feel free to take a look at them! There aren't any pictures though. :(
That's what makes blogger so good though. :)

And what about this child abduction emergency? Well look what I found on the national weather service website. The yellow for the state of montana? That is a "Child Abduction Emergency"

BULLETIN - EAS ACTIVATION REQUESTED
CHILD ABDUCTION EMERGENCY
MONTANA DEPARTMENT OF JUSTICE
RELAYED BY NATIONAL WEATHER SERVICE GREAT FALLS MT
1010 PM MDT WED OCT 6 2010

THE FOLLOWING MESSAGE IS TRANSMITTED AT THE REQUEST OF THE
MONTANA DEPARTMENT OF JUSTICE.

THIS IS AN ACTIVATION OF THE AMBER ALERT SYSTEM.

THE ALERT IS ISSUED ON BEHALF OF THE STATE OF WASHINGTON. WE HAVE
JUST RECEIVED THIS IMPORTANT INFORMATION REGARDING ABDUCTED
CHILDREN IN SPOKANE...WASHINGTON...SPOKANE COUNTY. WASHINGTON
STATE POLICE IN SPOKANE...DISTRICT FOUR...ARE LOOKING FOR
CHILDREN WHO WERE LAST SEEN AT WEST 1100 MALLON IN
SPOKANE...WASHINGTON...AND ARE BELIEVED TO BE IN DANGER. THE
CHILDREN/S NAMES ARE...

KALEB PHILLIPS...HE IS A 10 YEAR OLD WHITE MALE WITH BLONDE HAIR
AND BLUE EYES. HE IS BELIEVED TO BE FOUR FEET...WEIGHING 80 POUNDS.

DAWSON PHILLIPS...HE IS AN 8 YEAR OLD WHITE MALE WITH BLONDE HAIR
AND BLUE EYES. HE IS BELIEVED TO BE THREE FEET...WEIGHING 60 POUNDS.

BISHOP PHILLIPS...HE IS A 6 YEAR OLD WHITE MALE WITH BLONDE HAIR
AND BLUE EYES. HE IS BELIEVED TO BE THREE FEET...WEIGHING 50
POUNDS.

AUTHORITIES SAY THAT THE CHILDREN MAY BE IN THE COMPANY OF CHAD
PHILLIPS...HE IS A 33 YEAR OLD WHITE MALE WITH BLONDE HAIR AND
BLUE EYES. HE IS BELIEVED TO BE FIVE FEET...10 INCHES
TALL...WEIGHING 180 POUNDS. THEY MAY BE TRAVELING IN A 1996 DARK
GREEN CHEVROLET MONTE CARLO VEHICLE...INDIANA LICENSE NUMBER
IU4676. IF YOU HAVE ANY INFORMATION ON THE WHEREABOUTS OF THESE
CHILDREN...PLEASE CONTACT 509-456-2233 IMMEDIATELY.

My prayers go out to these children, and I hope they return safely. It is weird that the person beleived to have abducted them is Chad (nickname for Charlie) Phillips. I think it is kind of strange and a little funny that this is on a weather website, but child abduction itself is no laughing matter, and I will be praying for the welfare of these children. Just something I've never seen before.

Have a nice night (or good morning if you would prefer),
Charlie

What is El Nino Southern Oscillation? (ENSO)

El Nino and La Nina are both part of the El Nino Southern Oscilliation (ENSO) pattern in the eastern tropical Pacific ocean. This oscillation, or switching, refers to the temperature of the water in that region. In a La Nina phase, the water temperatures are cooler than normal, and in an El Nino phase, the water temperatures are warmer than normal. This is because in a La Nina phase, there is more upwelling in the eastern tropical Pacific, which brings cool, nutrient rich water up from the depths to the surface, and in an El Nino phase, there is decreased upwelling, so the water is more sterile and warmer. El Nino and La Nina both have different effects around the world, but since there are so many, I'm just going to talk about their effects in our location, the Pacific Northwest. Generally, El Nino will make us warmer and drier, while La Nina will make us cooler and wetter. Unfortunately for skiers, it looks like this year will be an El Nino year, with warmer and drier conditions prevailing during the winter. Still, we live in the Pacific Northwest, so we should get a good amount of snow anyway. And if there is no snow here this year, you can always head south to California during an El Nino year because the storm track is centered over them in El Nino years as opposed to us. In a La Nina year, the mountains get tons of snow because we are both wetter and cooler than normal. Especially in La Nina years, upper-level trofts from the Gulf of Alaska slide down south and direct cool and unstable air into our state. The Seattle metropolitan area usually is shadowed by these events, but the Cascades, who are perpendicular to this flow, commonly pick up foot after foot of snow. That is what happened during the 2007-2008 ski season, when Alpental, my local ski area, picked up 50 feet of snow. One interesting thing about El Nino and La Nina is that we generally do not have windstorms on these years. However, we can still get "Pineapple Express" flood events with El Nino and La Nina years.
Here's a great website to check out the tropical Pacific and see what it is doing. http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/sstanim.shtml
Somebody asked me about the probability of Pineapple Expresses in El Nino years as opposed to others, and here was my response.
Pineapple express events can happen in the El Nino, La Nina, and neutral phases of the ENSO, but they are most common in weak El Nino or neutral phases. Most Pineapple Express events are first set off by the Madden-Julian Oscillation. MJOs are pretty complex, but what they ultimately end up doing for the West Coast is bringing copious amounts of rain and warm temperatures via a long, "training" (staying in one spot, stalled) subtropical plume of moisture originating from the Hawaiian Islands or beyond (hence the name "Pineapple Express").
The thing is, in El Nino winters, a "blocking" ridge of high pressure usually sits off the Pacific Northwest, pushing the jet stream to the north and south. So while Southern Alaska and California (especially California) see enhanced precipitation, the Northwest is left dry. This means that even if an MJO produces a Pineapple Express event, it may not be pointed directly at the Pacific Northwest, which is the location most Pineapple Expresses over the past two years have been pointed. So while there may be more Pineapple Expresses, they may not be directly pointed at us.
Do you remember the huge landslides that occurred in Southern California several years back? I know for sure that they were associated with El Nino; they might have been associated with a Pineapple Express. The chance of Southern California, normally dry in the winter, getting extremely heavy rain will be much greater this year due to El Nino than other years. So if we aren't getting flooded, somebody else will be.

August 2009

August 27, 2009
1:34 P.M.

So, today I'll talk about our early autumn storms and our very tricky extended forecast. First of all, as most of you know, the tropics are very active in the months of august and september, since the warm water temperatures allow hurricanes and to develop. In October, when the northern regions have cooled significantly but the tropics are still warm, there is a large difference in temperature to support the development of extremely strong extratropical storms. Deep, tropical moisture is often entrained in low pressure systems at this time, and the differences in air temperature across the latitudes give the storm more fuel and make it stronger. The earliest major windstorm to hit the northwest, the Columbus Day Storm of 1962, was also the strongest, with gusts estimated at 195 mph at Cape Blanco, a headland on the Oregon Coast. I know this was a brief and maybe confusing explanation but frankly I just subjugated myself to an extremely intense workout and I can't really think straight right now.
The extended looks very complex. A "cut off" low pressure system (a low pressure system that stalls because it has been "cut off" from the jet stream) will heavily influence our weather over the next couple days. The models have been flip flopping a little, as these lows tend to have a mind of their own, but after a weakening system comes ashore Friday (rain will mainly stick to the coast) we will return to a pleasant late summer pattern with highs in the mid 70s and partly cloudy skies. I will be out of town Friday through Sunday to go tuna fishing. Wish me luck!
Thanks for reading,
Charlie


August 25, 2009
11:02 A.M.

Hey guys. Again, not too much new stuff to talk about. I don't know if any of you guys noticed, but there was a fairly decent marine push last night as a weak system came onshore. It opened all the doors in my house and kept me awake for a while (it was pretty loud).
Anyway, I am leaving to go tuna fishing Thursday night and I will be back late Sunday. Wish me luck! I'll have a more in-depth analysis of what to expect tomorrow, as well as some notes on what generally happens to the atmosphere when we begin the transition from summer to fall, and maybe talk about the rare but extremely powerful storms we occasionally see in early autumn.
Thanks,
Charlie

August 24, 2009
8:44 A.M.

Hey everybody. The forecast hasn't changed one bit, so I'm not going to make one right now. I hope you can understand.
Also, if you have any feedback for my blog or things you would like to see, post your ideas on the wall. It's always good to hear how this thing is working and what people want from it.
Thanks,
Charlie

August 23, 2009
9:36 A.M.

Ok, so this is the third time I've tried to write this forecast... I'm kinda sick of trying... so I'll do an update later today. My computer keeps crashing and spazzing out. Actually, what the heck I'll just do it right now and hope my computer doesn't repeat history. Anyway, there isn't really much new to talk about today as far as the short range forecast is concerned, but I thought I'd talk about El Nino and La Nina since we will be under the influence of El Nino this coming winter. El Nino and La Nina are both part of the El Nino Southern Oscilliation (ENSO) pattern in the eastern tropical Pacific ocean. This oscilliation, or switching, refers to the temperture of the water in that region. In a La Nina phase, the water temperatures are cooler than normal, and in an El Nino phase, the water temperatures are warmer than normal. This is because in a La Nina phase, there is more upwelling in the eastern tropical Pacific, which brings cool, nutrient rich water up from the depths to the surface, and in an El Nino phase, there is decreased upwelling, so the water is more sterile and warmer. El Nino and La Nina both have different effects around the world, but since there are so many, I'm just going to talk about their effects in our location, the Pacific Northwest. Generally, El Nino will make us warmer and drier, while La Nina will make us cooler and wetter. Unfortunately for skiers, it looks like this year will be an El Nino year, with warmer and drier conditions prevailing during the winter. Still, we live in the Pacific Northwest, so we should get a good amount of snow anyway. And if there is no snow here this year, you can always head south to California during an El Nino year because the storm track is centered over them in El Nino years as opposed to us. In a La Nina year, the mountains get tons of snow because we are both wetter and cooler than normal. Especially in La Nina years, upper-level trofts from the Gulf of Alaska slide down south and direct cool and unstable air into our state. The Seattle metropolitan area usually is shadowed by these events, but the Cascades, who are perpendicular to this flow, commonly pick up foot after foot of snow. That is what happened during the 2007-2008 ski season, when Alpental, my local ski area, picked up 50 feet of snow. One interesting thing about El Nino and La Nina is that we generally do not have windstorms on these years. However, we can still get "Pineapple Express" flood events with El Nino and La Nina years.
Here's a great website to check out the tropical Pacific and see what it is doing. http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/sstanim.shtml

August 22, 2009
9:05 P.M.

So I was out of town yesterday and most of today, but since I'm still back before the day is out, I thought I might entertain my friends and apprentices alike with another entry on my blog. The forecast looks pretty much the same; morning clouds and afternoon sunshine will abound. A few showers will occur Tuesday and Friday as decaying fronts, weakened by high pressure stationed over the eastern Pacific, clip our area. The extended forecast brings us warmer conditions for next weekend!
My pleasure,
Charlie

August 21, 2009
9:56 A.M.

Probably my favorite summertime weather (besides thunderstorms of course) is when we get a huge marine push after a hot spell. There's nothing I like more that sweltering in heat one day, leaving all the doors and windows open, and going to sleep with a cool refreshing breeze permeating throughout the house. Then when you wake up in the morning, you are shivering! There's no severe weather or tons of rain involved, but there is something to be said about a refreshing marine push after a stretch of hot weather. It's almost like going through microsoft word and getting all the typos out of your paper, or completely cleaning and reorganizing your room. It's like somebody just swept away everything and replaced it with something new. And although I love hot weather where you can go down to the beach or go fishing, I love it even more when everything is blown away and all you are left with are cloudy skies and cool temperatures. There is something really refreshing about that.
Anyway, these marine push events can only really occur when there is a heat wave to begin with. Our thermal troft- an area of low pressure west of us that draws in dry and hot air from the east- eventually shifts west because the predominant flow of the atmosphere in our latitudes is westerly. When this happens and the low is in eastern Washington, it now pulls in air from the west, which is cool and moist. That's why we are so cloudy and cool today; the thermal troft has passed to our east and is now drawing in cool air from the west, which we are under the influence of.
We should warm up a couple degrees this week, as highs will struggle to reach 70 today but should be in the mid 70s by next Friday, although there is a slight chance of rain for next weekend, which is our annual tuna fishing trip. Stay tuned...
Charlie

August 20, 2009
10:35 A.M.

There isn't really much new to report today. The convection that I speaked of a couple days ago possibly developing on the east side of the Cascades doesn't look like it is going to happen because there is not enough moisture. We will see a full-blown marine push event tonight, and tomorrow will look nothing like yesterday or today. I will be out of town starting tomorrow and I'm not sure exactly when I will get back but I'll be back by Sunday at the latest.
Charlie

August 19, 2009
10:45 A.M.

You always know how the media tends to hype up certain weather events, especially snow ones? Well as I read Cliff Mass' weather blog this morning, he brought to my attention that they hype up nearly every type of event, including heat waves. Let's examine the bias.
Jeff Renner is a very knowledgable forecaster, and I think he was a student of Professor Mass. Still, King5 News (In Mass' opinion the station that tends to hype things up the most) sent Jeff Renner out there with the goal to not provide a totally accurate forecast but to scare the public to get their attention (and therefore get more people to watch King5 News for "the latest" on the situation. Jeff Renner quoted the high temperature for Vancouver, Washington because it will be one of the hottest areas in the state today since it gets the Willamette Valley heat. And maybe Jeff Renner went on to explain that we, up by Puget Sound, won't be as hot because we are under more of a marine influence since we are right next to Puget Sound. Still, that's not what is going to stick in people's minds. Many people are going to subconsciously equate the Willamette Valley heat to what they can expect in Seattle. And to make matters worse, they have some extremely scary on-scene reporters. Like Jim Foreman. Check out the Cliff Mass Weather Blog @ http://cliffmass.blogspot.com/ . I have to say, the reason why Professor Mass is such a good professor is because he mixes extensive knowledge with charm and a great sense of humor and that he absolutely loves weather and does tons of things for the community to educate them even if it doesn't translate into any gain for him. He's just happy to share his passion, which I think is great.
The story remains the same... we will top out at about 90 degrees today and will begin cooling down Thursday. Friday, it will really be noticeable, as models predict that we won't break out of stratus clouds the entire day. Thursday will be 7-10 degrees cooler than today, and Friday will be nearly 20. For the rest of the extended forecast, we will be in a more typical summer pattern, with highs in the mid 70s and clouds in the morning burning off into clear skies in the afternoon or early evening.

August 18, 2009
11:33 A.M.

Today and the next few days will be absolutely beautiful. High pressure is over the region, and a thermal troft will develop over the coast, which will allow Seattle to be under the influence of dry and hot offshore flow off the Cascades. The good news is that this heat wave will be shorter, cooler, and much drier than our last one in late July into early August. Beginning Thursday, the offshore flow will switch to onshore, and by Friday, we will be back to normal, with highs in the mid 70s. This is a typical "marine push" event, in which the thermal troft shifts eastward, ushering in cooler oceanic air off the Pacific. Wednesday will be the warmest day, and we will likely reach 90 for the 8th time this year. The record, 9, was set back in 1958.
There is a slight risk of isolated thunderstorms Thursday east of the Cascade crest, and I also see some convection on the radar, where heavy showers are occuring on the north side of Mt. Rainier.
On an interesting note, some of the models at the UW Atmospheric sciences website show more vigorous low pressure systems developing. They are going to mainly go north, but still, this is a sign that fall is just around the corner. Go to http://www.atmos.washington.edu/~ovens/loops/wxloop.cgi?mm5d1_x_pcp3+%2F%2F%2F3 to see what I was looking at. The more active pattern can be seen in frames 40-60.
Have a great rest of the summer,
Charlie

August something, 2009 (welcome to summer... I think it's in the mid teens)
7:18 P.M.

Hey everybody. I thought I'd give an update since I haven't looked here for quite a while. I've been all over the Pacific Northwest lately and only been home for a couple days for the past month. I actually just got back from Portland, where I saw my uncle and some friends. I had a great time, but duty calls. Let's talk meteorology!
Ok, so the past month or so the weather has been rather cool. Since the heat wave died, we've been under a westerly flow, and cool air off the pacific has flooded into the region, giving us highs in the 70s and even only in the 60s some days. For the sun and heat lovers, I have some good news, though. We are going to see a much more traditional (as opposed to the last one) heat wave in the area. A thermal troft will develop offshore, which will turn the flow in our area from westerly to easterly. Now, instead of cool air coming off the ocean, you will have warmer continental air. To add to that, when the air slopes off the Cascades, it warms and dries as it is compressed (it is compressed since the pressure at sea level is higher than it is at places of elevation). That will give us clear skies and warm temperatures topping out at the lower 90s in the Puget Sound lowlands later this week, with Wednesday being the hottest day. After that, we will cool down a little, and expect some showers by next weekend.
Enjoy the rest of your summer,
Charlie

July 2009

July 30, 2009
4:03 P.M.

Today went as expected; highs were again near 100 or above near the foothills, but temperatures were in the 60s at the coast due to a strong onshore flow. For the rest of us in between, highs topped out at "only" the mid 90s. There aren't many situations where you can call 90 degrees cool, but this is one of them. Convection has again developed over the Cascades, but it isn't as strong or widespread as yesterday. In the meantime, we can expect a similar scenario of temperatures in the mid 80s until next week, when we will finally see the 70s again, which, may I remind you, are quite pleasant.


July 29, 2009
5:16 P.M.

Hottest day in the history of Seattle: July 29, 2009 (well at least so far).
Today officially broke the record for the hottest temperature ever measured at Sea-Tac airport. The thermometer reached 103 degrees today, 3 degrees hotter than it has ever been in Seattle. I'm on a limited time schedule since I'm on vacation at Whidbey, but I can give you some brief things and I will definitely later make a writeup about the hottest day in Seattle ever. Today was so hot, we were hotter than Tuscon, Arizona, which had a high of 101. How often does that happen?
Temperatures were even hotter towards the foothills, with readings of 110 degrees common in that area. There are some places where it has been dramatically cooler though. Due to the extreme temperatures and relatively humid air of this heat wave compared to others, strong thunderstorms have developed over the Cascades, and with no upper-level air movement to move them around, flash flooding has resulted. In fact, a FLASH FLOOD WARNING has been issued for the towns of Mineral, Elbe and Alder until 5:45 p.m. near Mt. Rainier due to stalled thunderstorm. Rain is falling at the rate of 2 inches per hour. Also, current doppler radar imagery shows a thunderstorm with TORRENTIAL rains; I'd estimate 3-5 inches per hour, developing in the geographic center of Snohomish county. I'm gonna try to convince my mom to drive me there so I can get some footage on my camera, but I don't think it's gonna happen. I'm vacationing with out of town guests who I must entertain. Now, if THEY want to see that thunderstorm, then I might be lucky. So those places, in addition to being flooded, the temperatures are much cooler. Also, the mercury at our beachhouse on Whidbey never climbed above 85 today since it is right at sea level. So, if you want to get relief from the heat without seeking air conditioning, go to the water or a thunderstorm.
Tomorrow looks very hot with highs at 100, but hey, that's cooler than today! Again, there will be thunderstorms in the mountains. Friday looks much cooler, with highs "only" in the mid-upper 80s. Monday and Tuesday, temperatures will finally cool into the 70s and more clouds will appear.

July 27, 2009
9:22 A.M.

Hey everybody. I just got back from a jazz camp in Port Townsend, and now I am vacationing around the state with some family friends.Right now, I am in Port Angeles.
So the weather for the next couple days looks rather eventful.We are going to be extremely hot as high pressure builds across our region and a thermal troft resides along our coast. A thermal troft is a weak area of low pressure that serves to give us not rain but hot and dry conditions.Since winds follow low pressure, a thermal troft on our coast will draw in winds from the east and west. Since we are to the east of the thermal troft, easterly downsloping winds will envelop us as they slope down the cascades. Due to adiabatic warming (the process of air warming and drying as a parcel of it decreases in elevation due to the characteristics and, most importantly, pressure, of our atmosphere,the air downsloping off the cascades will be very warm and dry when it gets down here.
You can check Komo for the actual forecast (or as they like to say, 4cast) but I can tell you that Wednesday will be our hottest day. Even along the coast, temperatures will break 90, and closer to the cascades at places like North Bend, where the forces of adiabatic warming are in full effect, temperatures will break 100. In Seattle, temperatures should peak out at just below 100, but it will be close. I'm going to say 99. Thursday should be a few degrees cooler, and Friday should be around 90. We won't see any definitive cooloff, but temperatures will settle into the mid-low 80s and clouds will be on the increase this weekend. It will also be interesting to see if any thunderstorms will come off the cascades as temperatures drop, but humidity increases.

July 14, 2009
3:13 P.M.

Yikes. Yet another long stretch of no forecasts. Oh well. It's summer. The more free time you have, the less you accomplish.
The fairly stable summer weather we have had recently will continue, and temperatures may even be above average for the next couple days, reaching into the 80s. Friday should be mostly sunny and the warmest day of the week, and highs will climb all the way up into the mid 80s. After this, however, we will get a typical marine push and temperatures will fall back down into the 70s. Whoops! Looks like it's time for me to get a haircut. Enjoy the beautiful weather!

July 2, 2009
2:44 P.M.

Well, I told you that I'd explain what a pyrocumulus cloud is, and explain I shall. Theo Floor entertained me with a guess that pyrocumulus are meteor showers, but unfortunately this is wrong. Props to Mr. Floor for trying though!
Pyrocumulus clouds are cumulus clouds formed by fires. Fires release vast amounts of heat into the air, and as this heat rises and expands, it condenses! This means that fires can create rain! Pretty interesting stuff, and pretty ironic as well.
The forecast remains the same as summer is in full swing around the region. Get outside and swim! It is fantastic beach weather and the lake has warmed up nicely.