The Art of Inconsistency

September 8, 2010
2:30 P.M.

Have you ever looked at one eather forecast one day, seen it as forecasting rain, then seeing the forecast switch to sun, only to have it switch back to rain? That is what is happening in the models right now, and it is very, very hard to make accurate forecasts when models can't decide what path to take with a certain storm. It makes it particularly hard if all the models are doing this, which is what they have been doing.

Thankfully, they seem to be converging on a solution of sun Thursday and Friday, with light rain returning Saturday night and Sunday. This is September, so the sunshine won't be your July sunshine, and the storm won't be your typical November storm. Things will generally remain quiet and benign around here as summer transitions into fall. Fall transitioning into winter brings the big storms, and winter transitioning into spring often brings instability and heavy showers, but summer to fall (and spring to summer) are both fairly quiet as far as weather phenomena go.

Our long range forecast shows this low pressure trough hanging around for a while, directing cool air from the northern Pacific right in our neck of the woods from a westerly direction. The mountains, especially the Cascades, will likely pick up some decent orographic (topographically enhanced) precipitation, but the Seattle area will likely get rain shadowed. It depends on how much onshore flow there is, but we could also see a PSCZ form, although it is hard to predict convergence zones one day in advance, much less 5 days. But if this scenario shown in the models were to come true, I would expect a convergence zone of some sort, likely near the eastern entrance to the Strait of Juan de Fuca. Also, I expect we will be seeing a lot of these upper-level lows (although this is a very weak one) dropping down from the Gulf of Alaska and directing a cool westerly flow into the Cascades. This type of setup is not conductive to a lot of rain in Seattle (shadowed by the Olympics) or lowland snow but snow levels are usually around 1000 feet in the winter with these types of setups and snow can really pile up in the Cascades. I remember one such event in early February 2008 where Snoqualmie Pass got 7 feet in 4 days. 2007-2008 was a La Nina year much like the upcoming one, and Snoqualmie Pass got 50 feet of snow (as opposed to maybe 20 feet last year). I'm excited for it and I hope you are too.

Here is the latest update on the SSTs in the tropical Pacific. As you can see, there is a wide swath of cooler-than-average temperatures. This swath is only expected to grow with time, and La Nina itself will really start to have an impact on our weather after Christmas, although it will certainly have an impact before then as well.

Hurricane Earl, Long-Range Pacific Northwest Weather Forecast

August 30, 2010
7:38 P.M.

Hey everybody, I apologize for not updating for like a month and a half, I've been out of town practically the whole time. I'm actually still not home yet, I'm in Denver visiting colleges.

Hurricane Earl has caught my attention. This system is now a major hurricane, and as of 9 o'clock EDT, it has sustained winds of 135 miles per hour and a central pressure of 938 millibars, putting it at category 4 status. This is an extremely dangerous storm and I would not be surprised if it intensified to a weak category 5. Looking at the infared satellite, I see cooling cloud tops (this means the storm is strengthening - the clouds are reaching higher into the atmosphere and therefore reaching a higher altitude with cooler temperatures) and I also see the absence of strong wind shear, which will prevent the storm from falling apart.

The east coast will feel the effects from this storm. Will it get a direct landfall? Probably not. This storm looks to make landfall up by Newfoundland, where it would have weakened significantly by then, becoming a category one or tropical storm. But there still is a possibility that this storm could in fact make a land fall on the East Coast, and I think it is more likely than others are making it out to be. Here's why.
The reason I think this is because the models may be a little too quick in breaking down an area of high pressure that is responsible for keeping earl going west. A cold front is expected to sweep away this high pressure system, and take Earl out northeast with it, but I think the models are a little too quick with the cold front based on their trends. Earl is expected to come closer to the coast now than before. Also, very strong hurricanes like Earl sometimes build their own high pressure systems ahead of them, because if air is rising somewhere (the eye of Earl) it must be sinking somewhere else (places ahead of the track). The saying "the calm before the storm" is a true saying, blue skies often precede violent storms because of this very reason.
The eye of Earl is also very impressive, look how tightly wound it is!

As for the extended forecast for this winter and beyond, we have a La Nina, and we are expected to have cooler temperatures and above normal precipitation, and looking at the Climate Prediction Center maps from NOAA at http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.php, it really looks like we will have a wet and cold winter. At least we are colored in darkly. The SSTs in the tropical Pacific aren't super cold yet, but that is the trend, and the Pacific Decadal Oscillation is in its cool phase for the Pacific Northwest. All these signs point to above average snowfall for us, not only in the mountains but in the lowlands as well! Keep your fingers crossed.

Charlie

Well into Summer

Thursday, July 15, 2010

9:52 A.M.

It's hard to believe that only a few weeks ago we were wondering if we were ever going to reach 75 degrees for a high. I, for one, was hoping for us to stay at 74 for the rest of the summer. In other words, have a nice, comfortable summer, but just keep the record going. Getting to 75 would be like stopping a marathon when you are on the closing stretch. But now that we have gotten all the way up to 95 this year, I don't want it to be 74! I want it to be 94! Maybe it is a little uncomfortable, but I really want the lake to warm up enough so that the perch start biting. Once the temperature gets above 70 degrees or so, they really start biting, and right now the temperature in the lake is around 65. Give it a couple more weeks and the lake will be teeming with hungry yellow perch. If you've never gone fishing in the lake, I highly recommend it off of any of the docks. Just go to Linc's tackle shop on rainier and they'll get you set up with everything you need.

What's the weather forecast looking like for this week and beyond? It looks like it will be dominated by a light onshore flow. This will keep things seasonable, with highs in the mid 70s and lows in the mid 50s. High temperatures will drop a couple degrees later this week as the onshore flow becomes more moderate. All in all, a pretty lame-duck weather situation. To give you an idea of how much the weather will change, look at the current situation above, and the one forecasted

The main thing we will see, technically speaking, is a retrogration of the ridge of high pressure to even further west out over the Pacific, allowing some cooler air from up north to sneak in via the jet stream.

The weather is frankly pretty boring around here during the summer, so what is happening around the world? The Atlantic is fairly quiet, but the big story that caught my eye were the record breaking dew points in the midwest. Places in Iowa had dewpoints over 90! That is absolutely unbearable. Anything above 60 is sticky. Once you get above 70, you are closing in on the torture zone. 90? That's unheard of.

Have a good one.

Charlie

Finally getting warmer

Thursday, July 1, 2010

4:40 P.M.

Remember how I said I didn't think it was going to get to 75 last week? Well, I was wrong. We finally broke the streak. I was hoping we could extend it as long as possible. Now that it is over however, I am ready for the heat. And it is going to get pretty hot around here!

We aren't talking about a major heat wave. However, the persistent trough that has been over us will finally move east, making way for a ridge of high pressure. This will cause an increased thickness over the atmosphere, which basically a way of saying the level between two millibar points in the atmosphere will increase due to increased temperature and/or humidity. Still, we wiull get above 80 easily next week, and we start to really feel the effects of summer on July 5th (as always).

I'm having problems with web pictures on blogger. I post them but it doesn't resize them to the correct resolution. If anybody could help me with this, that would be awesome.

Thanks and have a great day,

Charlie

I'm back!

Wednesday, June 23, 2010
12:38 P.M.

Hey everybody! After a long break from this website due to an extremely hectic schedule, school is officially out, and I have no reason at all to not be writing these forecasts. We have a lot to talk about.

The last day we got to 75 degrees was September 21. This means we have gone through all of fall, all of winter, and all of spring without getting once to 75. That is absolutely rediculous. We've gotten to 74 a few times, but we have not yet achieved that elusive 75. It's officially summer! I think it's rediculous that e haven't reached 75 yet, but I want this streak to keep going for as long as possible. All this for a summer that was originally thought to be warmer and drier than normal.

Today we have a very decent shot at getting to 75. It is 71 degrees now and we still have several hours before the day will be at its hottest (I've usually found this to be around 5 or so). Komo4 and many other tv stations believe we will get to 75 today. I'm not so sure. I woke up this morning and there was a light marine layer, which may have retarded the morning heating for our area. I also think that there are too many clouds to cause the temperature to get above 74. It will be very, very close however. The upper atmosphere has warmed a lot, and that's why many people think we will finally get above 75.

Some thhunderstorms may develop in the Cascades today. After today, things will cool down, and will have done so significantly by next week. It looks like we may once again find ourselves in the low 60s for highs, but this remains to be seen and confidence in the extended periods as of late has been rather low.

Thanks for looking!
Charlie