Wyoming SNOTEL Snow/Precipitation Update Report

Wyoming SNOTEL Snow/Precipitation Update Report

Based on Mountain Data from NRCS SNOTEL Sites

**Provisional data, subject to revision**

Data based on the first reading of the day (typically 00:00) for Friday, May 09, 2025

Basin Site Name	Elev (ft)	Snow Water Equivalent			Water Year-to-Date Precipitation
Basin Site Name	Elev (ft)	Current (in)	Median (in)	Pct of Median	Current (in)	Median (in)	Pct of Median
SNAKE RIVER
Basin Index (%)		85			99
MADISON HEADWATERS IN WYOMING
Basin Index (%)		70			93
YELLOWSTONE HEADWATERS IN WYOMING
Basin Index (%)		86			98
WIND RIVER
Basin Index (%)		92			104
BIGHORN BASIN
Basin Index (%)		93			97
SHOSHONE RIVER
Basin Index (%)		78			96
POWDER RIVER
Basin Index (%)		74			93
TONGUE RIVER
Basin Index (%)		104			100
BELLE FOURCHE
Basin Index (%)		*			90
CHEYENNE RIVER BASIN
Basin Index (%)		*			88
UPPER N. PLATTE
Basin Index (%)		70			90
SWEETWATER
Basin Index (%)		99			99
LOWER N. PLATTE
Basin Index (%)		53			78
LARAMIE RIVER
Basin Index (%)		61			88
S. PLATTE
Basin Index (%)		*			80
LITTLE SNAKE RIVER
Basin Index (%)		59			87
UPPER GREEN RIVER
Basin Index (%)		90			103
LOWER GREEN RIVER
Basin Index (%)		70			100
UPPER BEAR RIVER
Basin Index (%)		64			101

-M = Missing data.
* = Analysis may not provide a valid measure of conditions.
N/A = Not available.

Footnotes for median and average:
(##) = If less than 30 years are available, this value specifies the number of years used for the median and average calculations.
Sites with less than 10 years available do not have medians or averages.

If the Basin Index (%) percent value is flagged as potentially invalid,
care should be taken to evaluate if the value is representative
of conditions in the basin.

The SNOW WATER EQUIVALENT represents the depth of water in the snowpack, if the
snowpack were melted, expressed in inches.

The WATER YEAR-TO-DATE-PRECIPITATION represents total precipitation since October 1st, expressed in inches.

Contact your state water supply staff for assistance.

Medians and averages are calculated for the period 1991-2020.

Provisional data, subject to revision.

* Site -- Either: (a) the current value is missing; (b) the median or average for the day is not available or is zero; or (c) for snow water equivalent, the median or average for the day is less than 10% of the maximum median or average value for the year.

* Basin - More than half of the stations for a basin with normals report missing or invalid data.

The basin index is calculated as the sum of the valid current values divided by the sum of the corresponding medians or averages and the resulting fraction multiplied by 100.