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It wasn’t snow water or precipitation accumulation but rather high temperatures breaking records last month. With daytime temperatures reaching nearly 70 degrees Fahrenheit and night time temperatures staying well above freezing at most all SNOTEL sites many new high temperature records were set. This factor, in conjunction with a couple of warm rain events, helped push most all basins over the top and into the melt cycle. Most snow surveys this month indicated snow pack densities in the 40-48% range which means that most sites are on the verge of a major thaw. Even though the first few days of May have been cold and wet, short term weather forecasts indicate a trend toward warming and drying with freezing levels rising above 10,000 feet. The 90-day long range and summer forecasts predict drier than normal conditions however temperature forecasts are still up in the air.

The May 1 statewide SNOTEL readings were 140% of average, only slightly higher than last month. All basins have passed the normal peak accumulation period, generally April 1-15, and have entered the melt cycle. Easy Pass SNOTEL has the highest SWE ever recorded by a Washington SNOTEL site. On May 3, it recorded 124.6 inches of SWE, eclipsing the old record set by Paradise SNOTEL back on May 7, 1997 of 123.1 inches. During the month of April, the National Weather Service and Natural Resources Conservation Service climate stations reported above average precipitation totals throughout most Washington river basins.  Forecasts were refined this month but still vary from 93% of average for Icicle Creek to 139% of average for Ahtanum Creek, but for the most part remain unchanged from last month. Above average rainfall, snowmelt and normal reservoir operations led to mostly above normal runoff throughout the state.

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