This website provides real-time tracking and summaries of snow drought conditions across the western United States and Alaska using data from the Natural Resources Conservation Service SNOw TELemetry network (NRCS SNOTEL). The Phase Diagrams are described in detail in Hatchett et al. (2022) and show the daily progression (November-May) of accumulated precipitation and daily snow water equivalent (SWE) percentiles. Phase diagrams use hydrologic unit code 6 (HUC 6) river basin mean precipitation and SWE obtained from NRCS SNOTEL.
The statewide snow drought scatter plots show the snow drought classifications for a single point in time (most recent day) and for all individual SNOTEL stations within a given state. Dry snow drought is when both SWE and precipitation are below the 30th percentile, warm snow drought is when SWE is below the 30th percentile and precipitation is above the 50th percentile, and warm and dry snow drought is when SWE is below the 30th percentile and precipitation is between the 30th and 50th percentile. For both phase diagrams and state-wide scatter plots the SWE value is for the most recent day and precipitation value is the accumulation from November 1 through the current day.
Contact
For questions or comments please contact Dan McEvoy at the Desert Research Institute: mcevoyd@dri.edu
References
Hatchett, B. J., Rhoades, A. M., & McEvoy, D. J. (2022). Monitoring the daily evolution and extent of snow drought. Natural Hazards and Earth System Sciences, 22(3), 869-890.
https://nhess.copernicus.org/articles/22/869/2022/nhess-22-869-2022.html
NRCS SNOTEL. https://nwcc-apps.sc.egov.usda.gov/imap
