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, June 15, 2021
State   River Basin Snow Water Equivalent Water Year-to-Date Precipitation # of Sites Percent of Median # of Sites Percent of Median ALASKA   ANCHORAGE/SHIP CREEK BASIN 4/4 *   4/4 94      SUSITNA BASIN 2/5 *   3/5 87      NORTHERN KENAI MOUNTAINS 6/7 409*   6/7 91      SOUTHERN KENAI 3/6 *   5/6 98      COPPER BASIN 2/3 *   2/3 97      PRINCE WILLIAM SOUND 1/7 *   3/7 94      CHENA BASIN 5/7 *   6/7 105      UPPER TANANA 2/4 *   2/4 114      KOYUKUK BASIN 2/6 *   4/6 89      CENTRAL YUKON BASIN 0/5 *   2/5 77      NORTON SOUND 0/4 *   2/4 101      KUPARUK-SAGAVANIRKTOK RIVER BASIN 0/3 *   3/3 85      NORTHWEST ARCTIC RIVER BASIN 1/1 *   1/1 82      SOUTHEAST ALASKA BASIN 1/3 *   2/3 127    ARIZONA   VERDE RIVER BASIN 9/10 *   8/10 58      SAN FRANCISCO PEAKS 1/1 *   1/1 71      CENTRAL MOGOLLON RIM 4/4 *   3/4 52      LITTLE COLORADO RIVER BASIN 11/11 *   10/11 59      SALT RIVER BASIN 9/10 *   7/10 51      SAN FRANCISCO / UPPER GILA RIVER BASIN 8/8 *   7/8 60      CHUSKA MOUNTAINS 2/2 *   2/2 81    CALIFORNIA   NORTHERN GREAT BASIN 7/8 *   7/8 79      TRUCKEE RIVER 11/12 0*   11/12 55      LAKE TAHOE 11/11 *   11/11 58      CARSON RIVER 12/12 *   12/12 66      WALKER RIVER 7/8 0*   7/8 65    COLORADO   GUNNISON RIVER BASIN 15/16 *   15/16 78      UPPER COLORADO RIVER BASIN 32/35 0*   32/35 78      SOUTH PLATTE RIVER BASIN 21/22 0*   21/22 95      LARAMIE AND NORTH PLATTE RIVER BASINS 12/12 0*   12/12 81      YAMPA AND WHITE RIVER BASINS 20/22 0*   21/22 74      ARKANSAS RIVER BASIN 11/11 0*   11/11 98      UPPER RIO GRANDE BASIN 17/20 0*   18/20 97      SAN MIGUEL, DOLORES, ANIMAS AND SAN JUAN RIVER BASINS 20/21 0*   20/21 75    IDAHO   NORTHERN PANHANDLE REGION 10/10 1*   9/10 78      COEUR D'ALENE-ST. JOE RIVER BASIN 7/7 34*   7/7 82      CLEARWATER BASIN 16/16 51*   15/16 90      SALMON BASIN 20/20 0*   20/20 76      WEISER BASIN 4/4 *   4/4 77      PAYETTE BASIN 12/12 0*   12/12 76      BOISE BASIN 10/11 0*   10/11 76      BIG WOOD BASIN 8/9 *   8/9 66      LITTLE WOOD BASIN 4/5 *   4/5 59      BIG LOST BASIN 5/5 *   5/5 59      LITTLE LOST 3/3 *   3/3 70      BIRCH, MEDICINE LODGE, BEAVER, CAMAS BASINS 4/4 *   4/4 68      HENRYS FORK, TETON BASINS 8/8 2*   8/8 81      SNAKE BASIN ABOVE PALISADES 21/21 0*   21/21 83      WILLOW, BLACKFOOT, PORTNEUF BASINS 6/7 *   6/7 71      SNAKE BASIN ABOVE AMERICAN FALLS 29/29 1*   29/29 79      RAFT BASIN 2/2 *   2/2 70      GOOSE CREEK BASIN 2/2 *   2/2 70      SALMON FALLS BASIN 4/6 *   4/6 72      BRUNEAU BASIN 5/8 *   5/8 72      OWYHEE BASIN 8/12 *   9/12 71      BEAR RIVER BASIN 21/21 *   21/21 72    MONTANA   KOOTENAI RIVER BASIN 8/8 0*   8/8 87      FLATHEAD RIVER BASIN 14/17 61    14/17 95      UPPER CLARK FORK RIVER BASIN 14/14 77*   14/14 94      BITTERROOT RIVER BASIN 8/8 0*   8/8 97      LOWER CLARK FORK RIVER BASIN 9/9 40*   9/9 81      JEFFERSON RIVER BASIN 19/21 14*   19/21 82      MADISON RIVER BASIN 11/12 3*   11/12 82      GALLATIN RIVER BASIN 7/7 4*   7/7 86      MISSOURI HEADWATERS 31/31 7*   31/31 83      HELENA VALLEY 4/4 *   4/4 86      SMITH, JUDITH, AND MUSSELSHELL RIVER BASINS 7/9 0*   7/9 83      SUN, TETON AND MARIAS RIVER BASINS 5/6 0*   5/6 98      MISSOURI MAINSTEM RIVER BASIN 18/21 0*   18/21 90      ST. MARYS RIVER BASIN 2/2 81    2/2 89      MILK RIVER BASIN 1/1 *   1/1 109      UPPER YELLOWSTONE RIVER BASIN 21/22 2*   21/22 89      WIND RIVER BASIN (WYOMING) 11/13 0*   11/13 94      SHOSHONE RIVER BASIN (WYOMING) 6/6 0*   6/6 91      BIGHORN RIVER BASIN (WYOMING) 24/26 0*   24/26 90      TONGUE RIVER BASIN (WYOMING) 7/7 *   7/7 91      POWDER RIVER BASIN (WYOMING) 7/7 *   7/7 94      LOWER YELLOWSTONE RIVER BASIN 33/35 0*   33/35 92    NEVADA   NORTHERN GREAT BASIN 7/8 *   7/8 79      SNAKE RIVER 7/11 *   7/11 72      OWYHEE RIVER 6/10 *   7/10 71      UPPER HUMBOLDT RIVER 9/17 *   10/17 75      LOWER HUMBOLDT RIVER 6/10 *   7/10 89      CLOVER VALLEY & FRANKLIN RIVER 5/7 *   5/7 79      EASTERN NEVADA BASINS 5/14 *   5/14 85      SOUTHERN NEVADA - Spring Mountains 3/3 *   3/3 61    NEW MEXICO   RIO CHAMA RIVER BASIN 4/5 *   4/5 86      UPPER RIO GRANDE BASIN - New Mexico 10/12 *   10/12 88      SANGRE DE CRISTO MOUNTAIN RANGE BASINS 10/11 *   10/11 89      JEMEZ RIVER BASIN 3/4 *   3/4 68      SAN FRANCISCO RIVER BASIN 6/6 *   5/6 61      GILA RIVER BASIN 3/3 *   3/3 66      MIMBRES RIVER BASIN 2/2 *   2/2 58      PECOS RIVER BASIN 3/3 *   3/3 62      SAN JUAN RIVER BASIN 13/13 0*   13/13 79      ANIMAS RIVER BASIN 7/7 *   7/7 75      CANADIAN RIVER BASIN 6/7 *   6/7 96      ZUNI/BLUEWATER RIVER BASIN 1/1 *   1/1 72      RIO HONDO BASIN 1/1 *   1/1 73      CHUSKA MOUNTAINS 2/2 *   2/2 81    OREGON   OWYHEE 8/12 *   9/12 71      MALHEUR 3/3 *   3/3 77      GRANDE RONDE, POWDER, BURNT, IMNAHA 18/19 *   18/19 87      UMATILLA, WALLA WALLA, WILLOW 10/10 *   10/10 90      JOHN DAY 13/13 *   13/13 81      UPPER DESCHUTES, CROOKED 14/14 15*   14/14 83      HOOD, SANDY, LOWER DESCHUTES 9/10 70*   9/10 93      COAST RANGE 2/2 *   2/2 100      WILLAMETTE 20/23 15*   20/23 87      ROGUE, UMPQUA 12/13 16*   12/13 72      KLAMATH 18/20 *   18/20 65      LAKE COUNTY, GOOSE LAKE 6/7 *   6/7 63      HARNEY 11/12 *   11/12 82    UTAH   RAFT RIVER 2/2 *   2/2 70      BEAR RIVER 25/26 *   25/26 71      WEBER-OGDEN RIVERS 20/23 *   20/23 70      PROVO R.-UTAH LAKE-JORDAN R. 19/25 *   19/25 70      TOOELE VALLEY-VERNON CREEK 3/4 *   3/4 66      NORTHEASTERN UINTAHS 11/13 *   11/13 82      DUCHESNE RIVER 14/15 *   14/15 70      PRICE-SAN RAFAEL 8/14 *   8/14 65      DIRTY DEVIL 5/9 *   5/9 70      SOUTH EASTERN UTAH 5/11 *   5/11 72      UPPER SEVIER RIVER 17/23 0*   18/23 65      SAN PITCH RIVER 6/12 *   6/12 64      LOWER SEVIER RIVER 3/5 *   3/5 67      BEAVER RIVER 3/3 0*   3/3 72      ESCALANTE RIVER 4/5 *   4/5 62      SOUTHWESTERN UTAH 10/13 *   10/13 60    WASHINGTON   SPOKANE 9/9 34*   9/9 82      LOWER PEND OREILLE 5/5 0*   5/5 75      UPPER COLUMBIA 7/9 167*   7/9 94      CENTRAL COLUMBIA 11/11 77*   11/11 98      UPPER YAKIMA 6/7 *   7/7 96      NACHES 7/8 65*   7/8 95      LOWER YAKIMA 3/4 *   3/4 73      KLICKITAT 4/5 *   4/5 77      LOWER SNAKE, WALLA WALLA 13/14 *   13/14 88      LOWER COLUMBIA 14/17 158*   14/17 91      SOUTH PUGET SOUND 12/14 119*   12/14 98      CENTRAL PUGET SOUND 8/9 210*   9/9 101      NORTH PUGET SOUND 12/13 108    11/13 97      OLYMPIC 4/4 210*   4/4 92    WYOMING   SNAKE RIVER 22/22 1*   22/22 82      MADISON HEADWATERS IN WYOMING 4/5 0*   4/5 81      YELLOWSTONE HEADWATERS IN WYOMING 11/12 2    11/12 91      WIND RIVER 9/11 0*   9/11 93      BIGHORN BASIN 11/11 0*   11/11 87      SHOSHONE RIVER 6/6 0*   6/6 91      POWDER RIVER 7/7 *   7/7 94      TONGUE RIVER 7/7 *   7/7 91      BELLE FOURCHE 3/3 *   3/3 78      CHEYENNE RIVER BASIN 2/2 *   2/2 83      UPPER N. PLATTE 19/20 1*   19/20 79      SWEETWATER 3/3 *   3/3 82      LOWER N. PLATTE 4/4 *   4/4 81      LARAMIE RIVER 7/7 *   7/7 89      S. PLATTE 1/1 *   1/1 84      LITTLE SNAKE RIVER 8/9 0*   8/9 77      UPPER GREEN RIVER 14/15 0*   14/15 82      LOWER GREEN RIVER 10/12 *   10/12 85      UPPER BEAR RIVER 12/12 *   12/12 74

-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.