Ellensburg, just to the east of Snoqualmie Pass (see red A on map), is a really windy place in the summer. I mean windy. A listing of the winds (in knots, 1 knot=1.15 mph) and other weather is show below for the 24 h ending 1 PM today (times are in UTC--same as GMT). Strong northwesterly winds were evident (270 is west, 360 is north, etc), with...
Weak Front Moving Through
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A weak cold front is now moving into western Washington (see satellite and radar) imagery...with increasing clouds and a few light showers on the coast and NW washington. The onshore pressure gradient is rising (currently about 2.5 mb) and that will cause a modest influx of cooler, marine air overnight. So expect a cooling of 5-10F tomorrow and more...
Weather Politics
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This week I was in Boulder, Colorado at the National Center for Atmospheric research (NCAR) for the annual WRF model workshop. WRF stands for the Weather Research and Forecasting Model (pronounced WORF--like the security officer on the U.S.S. starship Enterprise). The WRF model is the main high-resolution weather simulation/forecast model used by the research community and most of the local weather predictions you see on the Atmospheric Sciences department web site (and which I show on this blog) are from WRF. It was designed to simulate down to ultra high resolution (e.g., the small turbulence eddies near the...
High Lows
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An interesting aspect of the weather of the past few weeks, has been the minimum temperatures. Most days have had minima above normal, while the maximum temperatures have gone above and below with relatively equal frequency (see first graphic). The drought is continuing even with the sprinkles of the last day-with June, a relatively dry month average,...
Good news and showers
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A few positive weather-related developments during the past week:1. It is looking like we will be able to save the observations taken on Washington State ferries--observations you can view on the Ferry Weather web site (http://i90.atmos.washington.edu/ferry/Ferryjs/mainframe1.htm). WA State Ferries has agreed to pay for the communication service a...
Close, but no cigar.
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We just missed breaking the dry-spell record by minutes...the official story by the National Weather Service....ITS OVER... A SHOWER THAT HIT SEA-TAC AT 0749Z BROUGHT 0.01 INCHES OF PRECIP TO THE AIRPORT BEFORE 08Z ENDING THE DRY STREAK AT THE AIRPORT AT 29 DAYS. (NOTE: THE DAILY MIDNIGHT TO MIDNIGHT DATA IS ACTUALLY FROM 1 AM TO 1 AM LOCAL TIME WHEN WE ARE ON DAYLIGHT SAVINGS TIME ). THE LAST TIME SEA-TAC GOT MEASURABLE PRECIP WAS BETWEEN 9 AND 10 PM BACK ON MAY 19TH.(Note: 0800 Z is 1 AM P...
No! It Can't End This Way!
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If it doesn't rain by midnight we will beat the all time record for consecutive days without rain at Sea Tac during May and June. But, look at the radar image at 8:44 PM...I can't believe it! A band of rain is approaching rapidly! It will take a miracle to save the record now.So if you know any meteorological incantations...this is the ti...
Record Tied
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For you record lovers...it didn't rain at SeaTac yesterday (I know there were some sprinkles elsewhere)....so we tied the record. The convergence zone was weaker than forecast last night and we have a very good shot of breaking the record today (longest dry run in May-June).Eastern Washington and the lower eastern Cascade slopes are very dry for this...
Will the record fall?
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Everyone likes breaking a weather record. Well, we are coming close to beating a "minor league" record...the record number of consecutive dry days in May and June at Sea Tac . The record is 29 days and we are right behind it now with 28. Check out this list of mega-dry periods at Seattle Tacoma Airport.29 DAYS MAY 28TH - JUNE 25TH 198228 DAYS...
Convection over the Mountains
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During the past week it has been completely dry over the western WA lowlands, but not over the crest and eastern slopes of the Cascades, where convection (cumulus, cumulus congestus, and cumulonimbus--thunderstorms) have developed each afternoon. A satellite picture from Friday afternoon shows an example (see image). I have also include radar images...
El Nino Returns
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Some major changes have been occurring in the tropical Pacific. Most of the last winter was characterized by La Nina conditions in which the surface temperatures of the central/eastern tropical Pacific were cooler than normal. But recently there has been a shift to the opposite, El Nino, where the water in that region is warmer than normal. The...
The Aftermath
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The marine push event of last Thursday appears to have resulted in the deaths of three individuals...all of which were on the water that evening. Strong marine pushes generally follow periods of above normal temperatures...which tempt people to get on the water. It is easy to forget how quickly things can change around here.And lets be honest about the forecast. The official predictions and model forecasts were clear that there was going to be a push, but no one expected it to be as strong as it was. I have studied these events extensively and have published several papers on them and it was only in the hour...
A Meteorologically Religous Experience
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I just experienced one of the finest weather experiences of my life. I knew a very major push was coming (see my previous post) and headed to the kite hill of Magnuson Park with my wife to experience it. We got to the top of the hill about 8:30 PM, with an extraordinary sunset...the sky aflame in orange and red. I looked to the south wherethe visibility was clearly less...a good sign of an approaching push (see my book for a discussion of this). It was warm up there, with little wind.And then IT hit. The winds started gusting and a veritable dust storm surrounded us. Some of the dust was from dirt paths, but...
All Hell is About to Break Loose
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The funny thing about the weather business is that when things happen, many things happen at once. Today and tonight is such a period.A powerful marine push is about to happen. Extraordinary onshore pressure differences have developed as the thermal low has shifted into eastern Washington. Look at the attached pressure differences . The difference...
Heat Wave
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Yesterday (Tuesday) got to 88F at Seattle and today should be very similar. There is one more day of the hot stuff (tomorrow could hit 90F) and then the marine air will move in for cooler temps on Friday and the weekend.Lets talk about some subleties of the heat. An essential ingredient is the thermal trough (see sea level pressure forecast at 2 PM)....
KCTS and Convection
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If you aren't tired of me yet, I will be on KCTS9 tomorrow (Tuesday) at 7 PM. I taped a one-hour weather talk a few weeks ago that will be shown, plus live questions tomorrow night (you can submit them on the web site)....By the way, there was some nice convection on the Cascades this afternoon....you can see it on the high-resolution satellite imagery...
