Tuesday, March 20, 2012

Spring begins for most, but
Winter stays strong out West

1:10 PM EDT 3/20/12 (Advisor/Meteorologist Justin Berk) While 2011-12 may have been "a winter without winter" for much of the East, a deep trough of cold air has recently produced heavy snow in the West from Washington state to northern Arizona. The enclosed graphic shows the extent of a heavy snowpack out west which has led to an extended ski season for some resorts in that region, including Lake Tahoe. 

Mt. Rainier, WA has been showing off it's heavy snowfall, as indicated by the  images comparing last summer to this week. That's incredibly deep snow! Look closely at the car height and smaller trees on the left and compare to the snow wall on the left. I estimate that is 10-15 feet in snow depth. Wow!

Even Flagstaff, AZ's recent "snowbowl" had a 7-day new snow total of 57". The colder than normal air made it all the way to Phoenix where Monday's high temperature of 58 F was 20 degrees BELOW normal. Contrast that with Baltimore's high of 75 F which was 20 degrees ABOVE normal and you have the extremes more or less balance out.

A warm Winter means 
a hot Spring or Summer?

The quick answer is, no! Back in the east, the end of a long regime of above-normal temperatures has been dangled out like a carrot all winter. It does look more likely that just as Spring begins, a temporary end of the warmth will become a reality. The current upper level pocket of cold air that brought Arizona snow and chill, is currently spawning severe weather in Texas and the deep South, is slowly moving east. That unstable weather should reach Maryland and the mid-Atlantic this weekend. Temperatures in that region should get closer to normal, in the mid 50s, with rain. This may be the first sign of a pattern change for April.

Looking at past years, the first comparison that jumps out is 1990. That year, Baltimore set record highs between March 12-15 with four days in a row in the 80s. The end of the following week, record snow fell on March 24th. Another comparison was the year 1946. The average high temperature was 10 degrees above normal (this current March is +7F). That year was followed by a return to a cooler spring and the pattern did flip in the summer. The three month period of June-August ended up 0.5F below normal. Not much, but a distinct swing from the end of winter. 

While pattern of each year varies, there is good indication that many regions under a drier than normal pattern may not swelter as like last summer. Keep in mind the past two winters were followed by more 100F+ days than many states have ever experienced in a two-year period. Not surprisingly, this extreme heat was followed by below-normal winters in terms of snowfall for those same regions.  

A reversal of fortunes this year? After all in 2011-12, many places accustomed to cold winters saved money on their heating bill, while others in the mid-South saw above-normal snowfall such as the early December 2011 event. Perhaps if this trend continues, the pattern can finally balance out with the majority of places having suffered under extreme conditions can equal out. A cooler and wetter summer might just do the trick, reducing need for air conditioning just as gas prices are beginning a record climb. 

At least we can dream, and hope it will turn out that way. 

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