Wyoming – NRCS

Report #23                                   Weekly Snow Report                             May 18, 2026

 

Good day to all. This is the 23rd Snow Report for Water Year 2026 (2025-2026 snow season). Currently the state’s SNOTELs are reading 33% of median with a basin high of 74% and a basin low of 3%. Last year the state was at 69%, and at 103% in 2024. The map may differ slightly from the table depending upon how many stations were reporting at the time. This report and a map displaying basin SWE percentages of median for the state may be found at: http://www.wrds.uwyo.edu/wrds/nrcs/nrcs.html.

 

For information on the use of median vs. average go to http://www.wcc.nrcs.usda.gov/normals/median_average.htm

 

SNOW WATER EQUIVALENT AS PERCENT OF MEDIAN. The following table shows the percent of median for today, the 2 previous weeks, one year ago, and two years ago for Wyoming basins. Normal (median) is based on all reporting SNOTEL sites in the basin with calculated medians (newer SNOTEL sites do not have medians figured), but does not include manually measured snow courses. The statewide SNOTEL percent of median is calculated by averaging medians for all stations associated with Wyoming basins. The weighted state average is figured using the area of basins (square miles). The reference period for computing medians is the 30-year period 1991 through 2020.

Basin	5/18/2026	5/11/2026	5/4/2026	5/18/2025	5/18/2024
Snake	39	47	62	80	90
Madison	43	50	65	62	77
Yellowstone	74	84	94	79	77
Wind	27	43	55	66	125
Bighorn	46	55	62	69	114
Shoshone	62	73	79	65	85
Powder	5	19	22	34	105
Tongue	19	45	50	78	107
Belle Fourche	*	*	*	*	*
Cheyenne	*	*	*	*	*
Upper North Platte	27	37	36	69	114
Sweetwater	3	19	37	65	150
Lower North Platte	16	2	3	17	151
Laramie	6	3	6	52	117
South Platte	*	*	*	*	*
Little Snake	25	30	31	57	119
Upper Green	32	45	53	79	93
Lower Green	29	31	29	67	115
Upper Bear	26	29	34	57	124
Statewide SNOTEL Percent of Median	33	41	49	69	103
Weighted State Average (Area)	24	30	35	51	98
Minimum	3	2	3	17	77
Maximum	74	84	94	80	151

 

red = down       blue = up      green = same       * Basin SWE values, close to dates of first measurable                                                                                                                      snowfall and melt-out, can be irregular or erratic

 

For more info contact:

 

Jeff Coyle Jeffrey.Coyle@usda.gov

(307) 233-6787

NRCS Snow Survey

100 East B St., Room 3124

Casper, WY 82601