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 Thursday, February 01, 2018
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 58    4/4 87      SUSITNA BASIN 2/5 82    3/5 109      NORTHERN KENAI MOUNTAINS 5/7 66    6/7 93      SOUTHERN KENAI 3/6 71    5/6 102      COPPER BASIN 2/3 115    2/3 131      PRINCE WILLIAM SOUND 1/7 39    3/7 112      CHENA BASIN 5/7 166    6/7 178      UPPER TANANA 2/4 120    2/4 143      KOYUKUK BASIN 2/6 167    4/6 148      CENTRAL YUKON BASIN 0/5 *   3/5 162      NORTON SOUND 0/4 *   2/4 149      KUPARUK-SAGAVANIRKTOK RIVER BASIN 0/3 *   3/3 147      NORTHWEST ARCTIC RIVER BASIN 1/1 179    1/1 174      SOUTHEAST ALASKA BASIN 1/3 49    2/3 80    ARIZONA   VERDE RIVER BASIN 9/10 22    8/10 18      SAN FRANCISCO PEAKS 1/1 28    1/1 22      CENTRAL MOGOLLON RIM 4/4 25    4/4 15      LITTLE COLORADO RIVER BASIN 11/11 26    11/11 17      SALT RIVER BASIN 9/10 20    8/10 15      SAN FRANCISCO / UPPER GILA RIVER BASIN 8/8 14    7/8 15      CHUSKA MOUNTAINS 2/2 9    2/2 28    CALIFORNIA   NORTHERN GREAT BASIN 7/8 50    7/8 80      TRUCKEE RIVER 11/12 43    11/12 81      LAKE TAHOE 11/11 42    11/11 82      CARSON RIVER 12/12 44    12/12 72      WALKER RIVER 7/8 46    7/8 68    COLORADO   GUNNISON RIVER BASIN 15/16 50    15/16 50      UPPER COLORADO RIVER BASIN 32/35 71    32/35 77      SOUTH PLATTE RIVER BASIN 21/22 84    21/22 99      LARAMIE AND NORTH PLATTE RIVER BASINS 12/12 85    12/12 92      YAMPA AND WHITE RIVER BASINS 20/22 72    21/22 73      ARKANSAS RIVER BASIN 11/11 45    11/11 58      UPPER RIO GRANDE BASIN 17/20 38    18/20 43      SAN MIGUEL, DOLORES, ANIMAS AND SAN JUAN RIVER BASINS 20/21 37    20/21 30    IDAHO   NORTHERN PANHANDLE REGION 10/10 114    9/10 110      COEUR D'ALENE-ST. JOE RIVER BASIN 7/7 113    7/7 110      CLEARWATER BASIN 16/16 110    15/16 111      SALMON BASIN 20/20 98    20/20 97      WEISER BASIN 4/4 67    4/4 88      PAYETTE BASIN 12/12 84    12/12 93      BOISE BASIN 10/11 75    10/11 88      BIG WOOD BASIN 8/9 78    8/9 82      LITTLE WOOD BASIN 4/5 86    4/5 96      BIG LOST BASIN 5/5 94    5/5 98      LITTLE LOST 3/3 100    3/3 95      BIRCH, MEDICINE LODGE, BEAVER, CAMAS BASINS 4/4 96    4/4 89      HENRYS FORK, TETON BASINS 8/8 104    8/8 101      SNAKE BASIN ABOVE PALISADES 21/21 111    21/21 106      WILLOW, BLACKFOOT, PORTNEUF BASINS 5/7 75    6/7 84      SNAKE BASIN ABOVE AMERICAN FALLS 28/29 105    29/29 101      RAFT BASIN 2/2 77    2/2 70      GOOSE CREEK BASIN 2/2 63    2/2 77      SALMON FALLS BASIN 4/6 65    4/6 83      BRUNEAU BASIN 5/8 59    5/8 86      OWYHEE BASIN 8/12 45    9/12 87      BEAR RIVER BASIN 20/21 86    21/21 85    MONTANA   KOOTENAI RIVER BASIN 8/8 114    8/8 106      FLATHEAD RIVER BASIN 13/17 124    13/17 117      UPPER CLARK FORK RIVER BASIN 14/14 126    14/14 119      BITTERROOT RIVER BASIN 8/8 112    8/8 104      LOWER CLARK FORK RIVER BASIN 9/9 114    9/9 108      JEFFERSON RIVER BASIN 19/21 123    19/21 102      MADISON RIVER BASIN 11/12 120    11/12 106      GALLATIN RIVER BASIN 7/7 132    7/7 117      MISSOURI HEADWATERS 31/31 123    31/31 106      HELENA VALLEY 4/4 134    4/4 118      SMITH, JUDITH, AND MUSSELSHELL RIVER BASINS 7/9 115    7/9 101      SUN, TETON AND MARIAS RIVER BASINS 4/6 113    4/6 120      MISSOURI MAINSTEM RIVER BASIN 17/21 122    17/21 114      ST. MARYS RIVER BASIN 2/2 101    2/2 108      MILK RIVER BASIN 1/1 112    1/1 156      UPPER YELLOWSTONE RIVER BASIN 21/22 145    21/22 130      WIND RIVER BASIN (WYOMING) 11/13 131    11/13 115      SHOSHONE RIVER BASIN (WYOMING) 6/6 140    6/6 131      BIGHORN RIVER BASIN (WYOMING) 24/26 128    24/26 112      TONGUE RIVER BASIN (WYOMING) 7/7 90    7/7 77      POWDER RIVER BASIN (WYOMING) 7/7 108    7/7 96      LOWER YELLOWSTONE RIVER BASIN 33/35 119    33/35 105    NEVADA   NORTHERN GREAT BASIN 7/8 50    7/8 80      SNAKE RIVER 7/11 60    7/11 83      OWYHEE RIVER 6/10 49    7/10 88      UPPER HUMBOLDT RIVER 10/17 47    10/17 78      LOWER HUMBOLDT RIVER 6/10 45    7/10 82      CLOVER VALLEY & FRANKLIN RIVER 6/7 43    5/7 75      EASTERN NEVADA BASINS 5/14 42    5/14 48      SOUTHERN NEVADA - Spring Mountains 3/3 22    3/3 46    NEW MEXICO   RIO CHAMA RIVER BASIN 4/5 30    4/5 35      UPPER RIO GRANDE BASIN - New Mexico 10/12 14    10/12 36      SANGRE DE CRISTO MOUNTAIN RANGE BASINS 10/11 24    10/11 42      JEMEZ RIVER BASIN 3/4 19    3/4 22      SAN FRANCISCO RIVER BASIN 6/6 17    5/6 15      GILA RIVER BASIN 3/3 14    3/3 15      MIMBRES RIVER BASIN 2/2 0    2/2 13      PECOS RIVER BASIN 3/3 12    3/3 34      SAN JUAN RIVER BASIN 13/13 37    13/13 27      ANIMAS RIVER BASIN 7/7 38    7/7 28      CANADIAN RIVER BASIN 6/7 11    6/7 37      ZUNI/BLUEWATER RIVER BASIN 1/1 18    1/1 6      RIO HONDO BASIN 1/1 5    1/1 42      CHUSKA MOUNTAINS 2/2 9    2/2 28    OREGON   OWYHEE 8/12 45    9/12 87      MALHEUR 3/3 50    3/3 86      GRANDE RONDE, POWDER, BURNT, IMNAHA 19/19 77    19/19 97      UMATILLA, WALLA WALLA, WILLOW 10/10 79    10/10 106      JOHN DAY 13/13 58    13/13 86      UPPER DESCHUTES, CROOKED 14/14 54    14/14 87      HOOD, SANDY, LOWER DESCHUTES 9/10 65    9/10 102      COAST RANGE 2/2 2400*   2/2 116      WILLAMETTE 21/23 56    21/23 96      ROGUE, UMPQUA 12/13 51    12/13 79      KLAMATH 18/20 41    18/20 78      LAKE COUNTY, GOOSE LAKE 6/7 52    6/7 83      HARNEY 11/12 46    11/12 82    UTAH   RAFT RIVER 2/2 77    2/2 70      BEAR RIVER 24/26 83    25/26 83      WEBER-OGDEN RIVERS 20/23 59    20/23 66      PROVO R.-UTAH LAKE-JORDAN R. 19/25 54    19/25 59      TOOELE VALLEY-VERNON CREEK 3/4 49    3/4 51      NORTHEASTERN UINTAHS 11/13 80    11/13 68      DUCHESNE RIVER 14/15 59    14/15 60      PRICE-SAN RAFAEL 8/14 41    8/14 53      DIRTY DEVIL 5/9 35    5/9 49      SOUTH EASTERN UTAH 5/11 37    5/11 38      UPPER SEVIER RIVER 17/23 43    18/23 47      SAN PITCH RIVER 6/12 44    6/12 55      LOWER SEVIER RIVER 3/5 45    3/5 52      BEAVER RIVER 3/3 35    3/3 37      ESCALANTE RIVER 4/5 32    4/5 36      SOUTHWESTERN UTAH 10/13 36    10/13 40    WASHINGTON   SPOKANE 9/9 110    9/9 110      LOWER PEND OREILLE 5/5 115    5/5 108      UPPER COLUMBIA 7/9 127    7/9 115      CENTRAL COLUMBIA 11/11 109    11/11 113      UPPER YAKIMA 7/7 107    7/7 107      NACHES 7/8 104    6/8 113      LOWER YAKIMA 3/4 77    3/4 98      KLICKITAT 4/5 85    4/5 99      LOWER SNAKE, WALLA WALLA 14/14 80    14/14 100      LOWER COLUMBIA 15/17 108    14/17 112      SOUTH PUGET SOUND 12/14 100    11/14 115      CENTRAL PUGET SOUND 9/9 100    9/9 111      NORTH PUGET SOUND 12/13 117    11/13 113      OLYMPIC 4/4 124    4/4 113    WYOMING   SNAKE RIVER 22/22 111    22/22 106      MADISON HEADWATERS IN WYOMING 4/5 115    4/5 109      YELLOWSTONE HEADWATERS IN WYOMING 11/12 145    11/12 133      WIND RIVER 9/11 128    9/11 112      BIGHORN BASIN 11/11 119    11/11 96      SHOSHONE RIVER 6/6 140    6/6 131      POWDER RIVER 7/7 108    7/7 96      TONGUE RIVER 7/7 90    7/7 77      BELLE FOURCHE 3/3 105    3/3 101      CHEYENNE RIVER BASIN 2/2 100    2/2 102      UPPER N. PLATTE 19/20 85    19/20 89      SWEETWATER 3/3 92    3/3 82      LOWER N. PLATTE 4/4 76    4/4 75      LARAMIE RIVER 7/7 100    7/7 106      S. PLATTE 1/1 33    1/1 111      LITTLE SNAKE RIVER 8/9 70    8/9 73      UPPER GREEN RIVER 14/15 107    14/15 102      LOWER GREEN RIVER 10/12 89    10/12 76      UPPER BEAR RIVER 12/12 87    12/12 83

-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.