Western US SNOTEL Snow/Precipitation Update Report

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
State River Basin	# 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	2/5	*	2/5	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	12/13	*	12/13	66
WALKER RIVER	7/8	0*	7/8	65
COLORADO
GUNNISON RIVER BASIN	15/18	*	15/18	78
UPPER COLORADO RIVER BASIN	32/36	0*	32/36	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	17/22	0*	18/22	97
SAN MIGUEL, DOLORES, ANIMAS AND SAN JUAN RIVER BASINS	20/22	0*	20/22	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	12/12	3*	12/12	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	22/22	2*	22/22	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*	11/13	74
KLAMATH	17/20	*	17/20	67
LAKE COUNTY, GOOSE LAKE	5/7	*	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.	19/26	*	19/26	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	5/12	*	5/12	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	2/4	*	3/4	73
KLICKITAT	3/5	*	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	5/5	0*	5/5	81
YELLOWSTONE HEADWATERS IN WYOMING	12/12	2	12/12	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.