4 PM Update...the Hoquiam-Seattle pressure difference is now 3.8 mb. A strong onshore push is thus guaranteed. Put up your wind chimes. It is coming. If anyone is planning on hitting the water...particularly in sail boats...please be prepared and careful. The winds will pick up later and get quite gusty.We had a minor intrusion of cooler air at low levels last night into the interior, but this thin veneer is rapidly getting mixing out...so temperatures will surge now back into the 90s...sorry. The coast is much cooler (60s). There should be a modest onshore push of marine air tonight...watch the difference...
Update III (Updated 10:45 PM)
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The 5 pm observations are in. Sea Tac got to 103F. Thunderstorms have developed and the clouds are spreading over the crests and foothills...beautiful anvils from space (see image). And low clouds have spread to the coast.Temperature ReadingsSeveral of you have been sharing temperature readings, which I and others really appreciate! But keep...
UPDATE II: The Record is Broken!
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It happened...Sea Tac is now 101 and STILL CLIMBING. Everett is an amazing 98 and Renton 102. And this is not over yet. We will not only break the record but smash it. Locations near the foothills are reaching 104- 106. This is an extraordinary event. Many stations will break their all-time record temperatures today and even more their daily values. Ballads will be written about the heat experienced today.Convection is forming over the mountains. Today I noticed altocumulus castellanus...midlevel convection... on this side of the Cascades. The focus of the convection may shift our way.... In fact, looking...
Update
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I don't know if I have ever seen temperatures rise this fast around here before. We had very warm air aloft and a very shallow inversion above the surface. This inversion was rapidly mixed out by surface heating and the easterlies aloft...thus, the rapid temp rise. Some of the warmest temps are in the foothills (e.g., North Bend) due to the downslope flow off the Cascades. In fact, with offshore flow the foothills can be the warmest locations in the whole region. The north Sound is much warmer today (now 93 in Everett)Probcast (www.probcast.com) is back up....the power outage on campus is over. I bet it was...
One Record Down, One to Go?
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Looking at the hourly data at Sea-Tac Airport, it appears that we have broken the record for highest minimum temperature in Seattle history. It was 69F and so far today the airport has only dropped to 71F, and it has subsequently rise...so that is probably it. This is a major record to break. At 9 AM Sea-Tac is 88F, 10F ahead of yesterday (due to...
Heat Update
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What is happening now is really amazing. The atmosphere above us has warmed substantially during the past 24-h. Seattle is 5F warmer than it was a day ago and the air aloft (measured by the Sand Point profiler) is about 6F warmer. The minimum temperatures this morning are considerable warmer this morning compared to yesterday morning. Clearly, today will be substantially warmer and SEA-TAC will get close to 100F today. Some warmer Puget Sound locations will get to the century mark. And remember, the Willamette Valley got to 100F yesterday...although they have done that many times (they don't have the cooling...
Major Heat Wave and Possible Record
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Today is running 7F ahead of yesterday, which got to 89F. It is clear that temps will get into the lower to mid 90s around the region today. Our most skillful tool for predicting temps...probcast..is now forecasting 102 for sea tac on Wed...this would be the all time record for any date in any year. Above is the probcast forecast for the max temps...
Thunderstorms and the Upcoming Major Heat Wave
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Last night there was some thunderstorms and rain from the central Sound northward associated with an upper level low/trough over the region (see upper level chart and radar image above and below). The action was greater to the north, particularly over southern British Columbia. Air rotates counterclockwise around lows and convection forming to the...
The Noctilucent Clouds Return and the Upcoming Heat Wave
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Many saw the noctilucent clouds again last night and a few of you sent some pictures. Above are some pictures provided by Reid Wolcott (top) and Dennis Bell. The "tendrils" of white and blue-white structures of these extraordinarily high (roughly 50 miles up) clouds are other worldly.The number of observations of these clouds seem to be increasing...
Drought and Heat
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This morning, Mark Albright of the UW shared these numbers with me:2009 is the driest 20May-19 Jul period on record using the combined SeaTac/downtown observations:2009 60 0.241925 60 0.421938 60 0.571922 60 0.611945 60 0.671911 60 0.722003 60 0.771965 60 0.791926 60 0.831927 60 0.87This is really an extraordinary drought we are in. And the surface "fuels" are tinder-dry in eastern Washington and in the Cascades.Tonight we will have a minor onshore push of marine air. The pressure difference between Seattle and the coast is now 2.7 mb and southwest winds are pushing through Shelton. It got...
Eastern Washington Smoke
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Today I flew to Cape Cod for a meeting on moving weather research to operations. I ALWAYS get a window seat. As we crossed the Cascades I was stunned on how murky it looked....there was clearly lots of smoke and it was pushed up against the eastern slopes of the Cascades. Take a look at this satellite picture from this morning....there is a significant...
When is the windiest time of the day?
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This time of the year there are real differences in wind speed during various times of the day and in virtually all locations it is windiest during the late afternoon. Take a look at the above trace of weather observations at my department at the UW (you can click on it to see a bigger version). Note: times are in GMT/UTC... 00Z is 5 PM, 18Z is 10...
The highest clouds of the world over Seattle
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Above is a picture taken after sunset at Seattle's Shilshole Bay Marina by Joseph Marsh on Tuesday evening. Just clouds? Not quite...these are very special clouds that are the highest clouds on earth...noctilucent clouds.These clouds are most commonly seen on clear nights north of roughly 50N during the summer months. They are located in the...
Amazing Amounts of Lightning
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There were nearly 35,000 lightning strikes over the area over the 48h period ending this morning around 7:30 AM. Pretty amazing. The graphic above is from the national lightning network-- a series of sensors that can receive the electromagnetic pulses produced by lightning.You will notice there is positive and negative lightning strikes indicated....
Thunderstorms
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We have some potentially interesting weather coming up. But not tomorrow. Saturday will be beautiful...warm (into the lower 80s over much of the lowlands) and dry away from the mountains. Up in the Cascades there is a slight chance of some convective showers. But nothing serious.And then there is Sunday. The air over us will be unstable, which...
My Weather DVD
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You have the book...now you can get the Northwest weather DVD! I am a strong supporter of Public TV and when they asked me to tape an introduction to Northwest Weather as a pledge gift, I was happy to do it. This hour-long presentation is a general introduction to Northwest weather and includes many of the graphics from the book. This was not easy...
Dry Sky Parties
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One of the inside jokes of the meteorological profession is that summer in the Northwest begins on July 12. And usually that is about right. June often is cloudy and gloomy (but not this year!), and sometimes showers darken the skies around the fourth of July. But in the later portion of July the climatological probability of precipitation plummets...
The Onshore Push has occurred
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As predicted, marine air has surged into western Washington. I can hear the leaves blowing outside my window right now..and the wind chimes are ringing. Just heaven! A weaker onshore surge than June 4th and one that started in the mid-afternoon--which is unusual...most wait until the evening....
Firework Pollution? and a Major Change
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Many times I have noticed that particles in the atmosphere tend to increase rapidly on July 4th...with a reduction of air quality. I took a look this morning...and it was there again..above is the trace at Puyallup and Queen Ann Hill from the excellent web site of the Puget Sound Clean Air Agency (http://www.pscleanair.org/airq/aqi.aspx). As you...
How Bad Has the Drought Been?
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We have been in an extraordinary dry period--and this does not bode well for the summer. Here is some fascinating statistics given to me by Mark Albright (who used to be State Climatologist). For the period May 20 through the end of June, Sea-Tac this year was drier than ANY OTHER YEAR in the 116 yr record (see numbers below). On .18 inches of rain....
