Wet but Calm

November 25, 2009

5:35 P.M.

Hey guys! Thanksgiving is less than a day away! I am soooooooo excited. Man... I haven't tasted that creamy mash potatoes that melt in your mouth infused with a concoction of gravy and stuffing for over a year. And the turkey... I just took a look at it. It's huge. And I'm going to eat as much as I can. We are also hosting an apple cider pressing party up at our beachhouse on Whidbey Island, where we will cut and grind apples and them press them to make apple cider. Let me know if you want some! I'm sure we will have way too much. It's great stuff and it is really fun to make too.

These two images show the expected rain from now to 4 A.M. tomorrow and then that time to 4 P.M. As the title says, the weather will be fairly uneventful this Thanksgiving in terms of wind and general storminess, but we should get a good shot of light but steady rain starting tonight and lasting into early Friday. All this rain is due to a front stalling over the area. Where most fronts sweep right on through, this front will have little eastward progress (storms go from west to east in our neck of the woods). Due to that, we could see an inch of rain throughout the lowlands, and the Skokomish could see some minor flooding. Still, the mountains will not see the prodigal widespread 5-10 inch amounts they were seeing with some of the systems earlier this November because the winds in the upper atmosphere will not be that strong, which means that there will not be much orographic enhancement on the mountain peaks. Of course, that means there won't be much of a rain shadow effect in locales like Sequim either. Everybody will be wet. And the snow levels will be high too, which is great news for travelers across the pass but bad news for us skiers.

I have to go eat dinner but I will be out of town until Sunday. Apart from some rain on Saturday the forecast looks pretty uneventful. Have a FANTASTIC Thanksgiving and thanks for reading. :)

Charlie

Benign Weather Week Ahead

November 24, 2009
4:37 P.M

Hey guys. Sorry for not making an update earlier... I had tons of homework and was studying for multiple large tests. Although I still have to do some stuff tonight, it is looking like a less strenous day tomorrow which means I'm not currently swamped at the moment. I am pretty tired though. I can't wait for Thanksgiving, which is my second favorite (and Christmas isn't even my favorite, its like Winter Break before Christmas that I absolutely adore) holiday (although technically that isn't really a holiday, in which case Thanksgiving would come in first (and sorry for all the parentheses btw)). Thanksgiving is my favorite Holiday for several reasons. First of all, there is delicious food. What is your favorite Thanksgiving dish? I personally die for a mix of stuffing, gravy, and mash potatoes. Write your answer below as a comment to this post!

I also love Thanksgiving because it is, on average, the stormiest holiday of the year. Although we will have rather pleasant weather this time around, there have been many a stormy Thanksgiving, and many of those have been celebrated in the dark, which really makes you thankful you have a roof over your head. Maybe Mother Nature is playing tricks on us. Such a situation occurred on Thanksgiving 1983.

The image above is taken from Wolf Read's "The Storm King" website, a website I highly recommend for anybody interested in severe weather events, particularly windstorms, in the Pacific Northwest. It shows peak gusts at the Sea-Tac airport for each day during the entire month of November 1983, which was really stormy in general. For the "granddaddy" of them all, the Thanksgiving storm made landfall just north of Hoquiam as a 972 millibar low. It delivered a powerful gale to the Puget Sound region with a 62 mile per hour gust at Sea-Tac. As I'm sure you can imagine, this type of wind, combined with the saturated soil I'm sure was present at the time from all of the previous storms, toppled trees and power lines across the region, making for many a cold turkey. Don't get me wrong, I love charred barbecue - it makes me feel like a true Northwesterner -, which is what many families resorted to during the time, but I like a fresh turkey out of an electrically-heated oven more. I'm not that tough.

This week will bring fairly benign weather to the region. Fronts will arrive Thanksgiving day and Saturday with showers in between before we see some drier weather setting up by next Monday. Have a good one folks!

Charlie

So... What Happened?

November 22, 2009

10:59 A.M.

Good morning everybody. Many of you guys weren't up late at night like me, but if you were, I'm sure you'd be asking the same question... "where is the wind?"

Well, the surface low, instead of taking a track towards the central Washington coast like the models showed, took a track towards Astoria. This southern track put us further from the low which gave us less wind and put the Olympia/Southwest Interior area right under the low, where there is also a weak pressure gradient and not much wind. Why was there this short term forecast failure? Simply because of one thing. We don't have a coastal radar. If we did, we would not have this problem. All of the high wind warnings that were put up would either be wind advisories or nothing at all, and devoted weather maniacs like me would have actually fallen asleep instead of staying of late to see if the winds were going to come.

On the plus side, one part of the forecast went very well. There was tons of snow in the mountains! More on that later... I g2g

Update on Surface Low

November 21, 2009

10:07 P.M.

Hey everybody. I just got back from eating some delicious Indian food so I thought I'd make an update on the forecast as far as winds are concerned for tonight.

Here is the water vapor imagery for . This satellite shot shows the amount of water vapor in the atmosphere. Notice the "dry slot" behind the storm headed towards us. A pronounced dry slot is a telltale sign of an intense low pressure system or one that is still developing. Even when the storm is not visible on the infared satellite, a dry slot can often be observed on the water vapor one.

Here is the infared satellite. In the past few hours, a "bent back occlusion" has developed, which is where the occluded front wraps around the low pressure center. This is also conductive of a vigorous and intensifying low pressure system.

I really can't give a straight forecast (a coastal radar would really help here!) but I don't think the Seattle area will be too windy. Still, we have a wind advisory from midnight till 10 A.M. tommorow I think for gusts up to 45 miles per hour. The southwest interior and coast still have high wind warnings. Also, something I forgot to mention earlier was that this storm will bring a very strong westerly surge of wind down the Strait of Juan de Fuca after it passes early Sunday. Expect winds up to 70 miles per hour there as well.

Charlie

An Intense Low and SNOW!!!

November 21, 2009

1:38 P.M.

Look at the graphic above. It shows the track of the vigorous low I was talking about in earlier posts. This low looks like it will not bring high winds to our area, but the coast and southwest interior could get slammed.

Usually we don't see winds as strong as forecasted (gusts to 70 miles per hour) with lows this deep (this low is only 990 millibars). Winds, however, are not determined by the absolute barometric minimum of the low. Rather, they are determined by the gradient of low pressure. This is a small-scale, surface low pressure system that will still be in the development phase when it comes ashore. All these factors combine to make a very steep pressure gradient. I would not be surprised in the slightest to see a gust to 90 miles per hour in one particular spot - Naselle Ridge in the SW coastal mountains. This place commonly receives high winds, and a similar (albeit much stronger) event on November 3, 1958 gave it a 161 mile per hour gust. Go to http://www.climate.washington.edu/stormking/November1958.html for more information on this storm. The Seattle area should not see strong winds from this storm.

Another aspect of this storm is that it will bring tons of snow to the mountains! Take a look at the 4km mm5-gfs mesoscale model. Amounts of 30-40 inches are seen throughout the Olympics and amounts of 2-3 feet are seen in the Cascades, with even even higher amounts at higher elevations like Mt. Baker and Mt. Rainier.

Even Seattle will see a fair amount of rain from from this storm. From 4 P.M. Saturday to 4 P.M. Sunday, I'd expect an inch of rain here in Seattle, and the rain will be heavy at times tonight. The coast will see higher amounts, with local amounts up to 4 inches possible.

After this, we will get into a MUCH more benign weather pattern with only a few weak systems approaching the NW. One will clip the area Monday and showers will persist through Thursday. After that, Thanksgiving weekend looks completely dry! I'm not too happy about that but I bet a lot of other people are. After getting all the new snow we should pick up in the next day and the additional stuff during mid-week, the weekend should make for some fantastic skiing in the mountains. I'm definitely going to try to check that out. :)

Have a good weekend,

Charlie