Olympic Peninsula snowpack at 27%

The Olympic Peninsula’s snowpack dropped to 27% of median as of May 21, according to the Port Townsend & Jefferson County Leader, extending a season of unusually low mountain snow in Washington. The figure puts the peninsula well below normal late in the spring melt season, when snowpack is still a key source of runoff for rivers, reservoirs and ecosystems. State and federal monitoring had already shown the Olympics among Washington’s weakest snow regions this year. By early May, the Washington State Climate Office said warm and dry weather had pushed snowmelt faster than normal across much of the state. ### Why does 27% of median matter this late in May? The 27% figure refers to snow water equivalent — the amount of water stored in the snowpack compared with the 1991-2020 median for the same date. On the Olympic Peninsula, that means the remaining mountain snow holds only a little more than one-quarter of the water that is typical for May 21. USDA’s snowpack reports use that same median-based measure to track how much runoff may still be available as temperatures rise. (ptleader.com) May 21 is also well past the normal peak of Washington’s snow season. The Washington State Climate Office said statewide snowpack usually peaks in early April and then melts gradually through April, May and June. This year, it said, snowpack peaked two to three weeks early and then declined quickly during the second half of April and into early May. (nrcs.usda.gov) ### How unusual has this spring been in Washington? Washington entered April with statewide snowpack at 53% of median, according to the Washington State Climate Office, which said deficits were largest in the Olympics, central Cascades, Blue Mountains and Okanogans. The office said that level was near the 5th percentile, meaning statewide snowpack was lower than 95% of years on record since 1985. (climate.uw.edu) By May 12, the climate office said statewide snowpack had fallen further to 33% of median as of early May. It said most sub-basins across the state were below 30% of normal snow water equivalent by May 4, and that low-elevation stations in the Cascades and Olympics had fully melted out. ### What drove the Olympic Peninsula decline? (climate.uw.edu) The Port Townsend & Jefferson County Leader said rapid spring melt and higher-than-normal temperatures contributed to the decline on the Olympic Peninsula. The Washington State Climate Office described the broader state pattern in similar terms, saying warm and dry conditions caused snow to melt more quickly than normal this spring. (climate.uw.edu) A March snow event briefly added to mountain snow, but the climate office said a later warm spell removed around half of those gains statewide. It said that melting likely pushed the peak snow-water-equivalent date about two weeks earlier than normal in many basins. ### Does this fit a wider drought picture? Washington’s Department of Ecology issued a statewide drought emergency on April 8 because of very low snowpack and summer water-supply concerns, the Washington State Climate Office said. (ptleader.com) The office also said many major river basins were expected to receive less than 75% of normal water supply. (climate.uw.edu) The Olympic Peninsula does not depend on snow in the same way as every irrigated basin east of the Cascades, but mountain snow still matters for late-spring and summer streamflow. The climate office said early melt can also set the stage for a longer fire season because fuels dry sooner. ### What should readers watch next? (climate.uw.edu) June is the next key checkpoint for this story. USDA’s Washington water-supply outlook and daily snowpack updates will show how much snow remains in the Olympic Basin, while Washington drought reporting will track streamflow and summer water-supply conditions. The Port Townsend & Jefferson County Leader’s May 21 report provides the local benchmark: 27% of median on the Olympic Peninsula. (climate.uw.edu) (nrcs.usda.gov)