What is Snow Drought?
Snow drought is defined as period of abnormally low snowpack for the time of year, reflecting either below-normal cold-season precipitation (dry snow drought) or a lack of snow accumulation despite near-normal precipitation (warm snow drought), caused by warm temperatures and precipitation falling as rain rather than snow or unusually early snowmelt. (AMS Glossary of Meteorology)
Current situation and impacts in the West
This June 21 current situation update will be the last for the 2018 Water Year as snowpack and snowmelt are past peak values. Updates will resume in the 2019 Water Year (October 2018). Access to the tools is available year round.
June 21, 2018:
Most snow-monitoring sites have already melted out in Oregon, California, southern Idaho, Utah, Colorado, and northern New Mexico, and the remaining higher-elevation snowpack in these areas is well below normal.. A few sites in the northern Rockies are still well above normal snowpack, continuing to contribute to above normal streamflows in places like Montana. Alaska is not shown as most snow-monitoring sites have already melted out. [This is the final update of the 2018 Water Year]
USDA Natural Resources Conservation Service (NRCS) percent of 1981-2010 median snow water equivalent (SWE) over the western U.S. for June 18, 2018. Only stations with at least 20-years of data are shown. For an interactive version of this map, including percent of period of station record median SWE, please visit NRCS.
SNOw Data Assimilation System (SNODAS) percent of average (2003-2018) snow water equivalent (SWE) for June 17, 2018. Percent of average SNODAS processed using Climate Engine. Please note the shorter historical period of this dataset compared to the station data above.
SNOTEL basin-wide average SWE (inches) time series for Baker, Skagit, and Nooksack in the northern Washington Cascades from June 19, 2018. Black line is this year and red line is the 1981-2010 median. The regional SWE peaked higher than the median value in April, but is now near the median value.