WSU AgWeatherNet reports warmer Spring good for growers

PROSSER, Wash. – After 2011’s chilly spring temperatures, this spring was a relief to Washington’s growers. Although not unusually hot, the relative warmth was welcome, especially when compared to the record cold and the associated crop damage of last spring.

“Despite periods of seasonally cool weather, no major frost or weather-related crop damage has been reported during the early portion of Washington’s 2012 growing season,” said Washington State University AgWeatherNet Director Gerrit Hoogenboom. “Unlike 2011, Mother Nature has for the most part cooperated with Washington’s agricultural interests this year.”

Overall, temperatures were around average during the March to May period. Spring temperatures at the WSU Prosser Research and Extension Center were 3.3 degrees warmer than last year, while May temperatures were 3.6 degrees warmer.

“This spring has featured significant temperature variability, as well as several episodes of hot, summer-like weather — two things not seen in great abundance last year,” said AgWeatherNet meteorologist Nic Loyd. “The persistently cool and unsettled weather of last spring was characterized by a notable lack of heat or large temperature fluctuations.” Spring 2012 rainfall was slightly above average at WSU Prosser due to a wet March and April but, again, conditions were notably drier than last spring.

March was somewhat cool and wet, with Long Beach recording 15 inches of rain during the month, including 3 inches on March 12. Notable weather events included snowfall at coastal regions on March 12, and cold and snowy conditions from Pullman to Spokane on March 21. By contrast, April was quite warm and featured an unusually early heat wave that led to several AgWeatherNet monthly high temperature records.

On April 23, Moxee, Prosser and Wenatchee weather stations all recorded highs in the upper 80s, temperatures more typical of July than April. Many areas recorded warmer monthly maximum temperatures during the April 2012 heat wave than during June of 2011, even though June is typically 15 degrees warmer than April. The Prosser station recorded the warmest April average low temperature since 1994, while the monthly average high temperature was seven degrees warmer than last April. April 26 was a uniquely wet day in Washington, with all 138 AgWeatherNet stations recording rainfall.

May temperatures were slightly below average, despite being warmer than the previous year. May 2012 rainfall at WSU Prosser was less than half of the monthly average, and much less than in May of 2011. The month began with unsettled and cool conditions, as Long Beach recorded 0.8 inches of rain, while Paradise, at Mt. Rainier, received one foot of snow on May 3rd. The presence of very dry air led to large temperature fluctuations during the middle of May. A few locations experienced cold morning temperatures, while summer-like heat returned a few days later.

The temperature at the AgWeatherNet station near Moxee fell to 27 degrees on May 10, while Pullman recorded a brisk 25 degrees on the morning of May 11. May also featured one episode of particularly hot weather around mid-month. The high temperature at Vancouver climbed to 86 degrees on May 13, while the mercury in central Washington rose above 90 degrees on May 15. Last May, most areas in central Washington did not even reach 80 degrees, with Vancouver barely surpassing 70 degrees.

The hot and sunny weather was followed by a very unsettled period from May 21 to 24, which brought the first significant rain in several weeks to Washington. Long Beach received over 2 inches of rain during the active period, while parts of eastern Washington recorded around three quarters of an inch. Significant snow also fell at Mt. Rainier during the cool period, with over 6 inches at Paradise. Clouds and windy conditions caused very cool daytime temperatures, with Pullman and areas west of the Cascades climbing only into the mid-50s on May 22.

For more information on Washington’s spring weather, as well as other weather information, please see the Spring Weather Review on the AgWeatherNet website, www.weather.wsu.edu, located under the News link. A Web based, publicly available system, AgWeatherNet provides access to near real-time weather data and value-added products from WSU’s statewide weather network, along with decision aids for agricultural producers and other users.