Aircraft wake turbulenceLast night I was flying back to Seattle from the Bay Area and it got fairly bumpy at times, with the pilot periodically putting on the seat belt sign.What were the origins of that turbulence?The cause last night was vertical wind shear, a large change in wind speed/direction with height. We were not flying in clouds or storms,...
OutdoorFun Winter Weather Index: A Record Tying Year!
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You come to this blog for the latest information on weather prediction. Cutting edge technology and modeling. Today we will push the envelope with the latest UW advance:The OutdoorFun Winter Weather Index (OWWI)When do you feel comfortable working and playing outside? 40s are too cold for most. 50, 51, 52 a little bit chilly and you still need...
Inversion and A Significant Change
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We clear skies and light winds we had perfect nighttime weather for the development of an inversion last night (remember, inversions occur when temperature increases with height). Take a look at the Sand Point observations ending 10 PM last evening. Temps in degrees C and height in meters. The yellow line was for 4 PM...no inversion then. But you...
Big Diurnal Range in Temperature
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During the last two days we have had something we haven't seen in a while. No, I am not talking about highs near 60F...although that is true. What we have had is a very large diurnal (daily) range of temperature. Look at the plot above at Sea Tac, today the high was 59 with a low of 39F, a 20F temperature range....far greater than we have had since...
Sunny Skies are Good For Olympic Snow
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The forecasts for the next four or five days at the Olympic venues is for lots of blue skies and sun. No snow. None.Believe it or not, this is very good for maintaining snow at Whistler and Cypress Mountains! The worst of the snow melt is over. The games will be ok.So why is sun and lack of clouds and rain a good thing?It turns out that the very...
Ridgodzilla
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What is very big, very persistent, brings lots of heat on one side and chills on another? A huge ridge and blocking pattern...or in meteorological parlance-- RIDGODZILLA! And its coming to a winter Olympics in your neighborhood!Take a look at at series of upper level (500 mb pressure level) charts starting Wednesday at 10 AM. You will notice substantial...
Olympics Weather Forecast: Heavy Rain and Fog
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Current condition at the top of Whistler: FOG!!I hate to say it, but for the next day the weather for the Olympics venues will be better for surfboarding than snowboarding. Heavy rain. Thick fog. Not luge, but deluge.Bringing snow to Cypress Mt.Lets face it. Our Canadian friends were mighty unlucky...a moderate El Nino at just the wrong time....
The Northwest Weather Workshop
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On March 5th and 6th there is the Northwest Weather Workshop, the annual gathering for local folks interested in Northwest weather. There is always a wide range of interesting weather talks and roughly 70% are quite accessible to laymen. Everyone from local TV weather and university types, to NWS forecasters, private sector meteorologists, and weather enthusiasts. The meeting takes place in north Seattle at the NOAA Sand Point facility.The meeting is open to everyone, but you should register if you are going. There is also a Friday night banquet, with the speaker this year talking about weather and wine growing....
Why dense morning fog is a good sign!
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You wake up and look outside only to find amazingly dense fog. Like the example above. You can barely see across the street, if that. Time to get depressed about another cloudy day? Pull the covers over your head and think of Maui? No way! Super dense fog is ironically a very good sign...one suggesting a sunny day ahead. Get out your sunglasses and...
Humility and Forecast Busts
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Weather Prediction is a Stern MasterWeather prediction is a business that promotes humility, and nothing brings one down to earth like a forecast failure--known as a "forecast bust" in the business. Major forecast failures are less frequent than even a decade ago...mainly due to a huge increase in satellite data and better computer models... but they...
Why was January so warm? A detective story.
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As I mentioned in an earlier blog, January 2010 was the warmest on record in Seattle (back to 1891) and one of the warmest years at virtually every western Washington site with long records. This is a major record. The big question is why? What was so extraordinarily unusual last month?Yes, it was an El Nino January and they tend to be warm...but...
Mis-communicating Global Warming
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As many of you know from my previous blogs, I believe that anthropogenic global warming (AGW)--warming due to mankind's emissions of greenhouse gases--is a very serious issue. The world's climate will warm up substantially if we continue our current course. I also believe that there has been considerable hype of past and current effects of man-produced...
Records Broken (UPDATED) and Alligators in the Duwamish
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Its official!JANUARY 2010 WAS THE WARMEST JANUARY ON RECORD IN SEATTLE INCLUDING THE RECORDS FROM THE FEDERAL BUILDING THAT GO BACK TO 1891. Yes, 1891.This is a major new record.Seattle had a mean temperature in January of 47.0F. The old record was 46.55F in January 2006. Take a look at this table of Seattle-Tacoma Airport observations. The fifth...
