Summary of Western US 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 Tuesday, February 20, 2024
State/River Basin Snow Water Equivalent Water Year-to-Date Precipitation # of Sites Percent of Median # of Sites Percent of Median Alaska 28/59 119    47/59 102    Arizona 21/23 131    19/23 90    California 32/32 85    32/32 86    Colorado 100/105 95    103/105 94    Idaho North of Salmon River 30/31 60    30/31 76    Idaho South of Salmon River 65/65 92    65/65 95    Montana 87/91 65    87/91 76    Nevada 30/32 124    31/32 115    New Mexico 21/21 116    21/21 95    Oregon 78/81 93    78/81 104    Utah 89/90 115    90/90 108    Washington 69/76 58    67/76 86    Wyoming 82/85 87    82/85 97    Arkansas River Basin 6/6 102    6/6 96    Colorado River Basin 104/108 99    106/108 98    Columbia River Basin 261/266 74    261/266 91    Missouri River Basin 45/48 67    45/48 80    Rio Grande River Basin 28/29 100    29/29 92    The Great Basin 104/105 106    105/105 103

-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.