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 Wednesday, December 29, 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	126	4/4	121
SUSITNA BASIN	1/5	60	3/5	89
NORTHERN KENAI MOUNTAINS	6/7	107	6/7	116
SOUTHERN KENAI	2/6	75	4/6	84
COPPER BASIN	2/3	73	2/3	54
PRINCE WILLIAM SOUND	1/7	119	3/7	87
CHENA BASIN	4/7	262	5/7	225
UPPER TANANA	2/5	193	2/5	180
KOYUKUK BASIN	2/6	203	4/6	142
CENTRAL YUKON BASIN	0/5	*	3/5	202
NORTON SOUND	0/4	*	2/4	121
KUPARUK-SAGAVANIRKTOK RIVER BASIN	0/3	*	3/3	134
NORTHWEST ARCTIC RIVER BASIN	1/1	162	1/1	129
SOUTHEAST ALASKA BASIN	1/3	127	1/3	68
ARIZONA
VERDE RIVER BASIN	9/10	146	8/10	103
SAN FRANCISCO PEAKS	1/1	149	1/1	117
CENTRAL MOGOLLON RIM	4/4	117	4/4	88
LITTLE COLORADO RIVER BASIN	11/11	124	11/11	93
SALT RIVER BASIN	9/10	85	8/10	74
SAN FRANCISCO / UPPER GILA RIVER BASIN	8/8	43	7/8	43
CHUSKA MOUNTAINS	2/2	175	2/2	115
CALIFORNIA
NORTHERN GREAT BASIN	7/8	158	7/8	159
TRUCKEE RIVER	11/12	240	11/12	223
LAKE TAHOE	11/11	230	11/11	222
CARSON RIVER	12/13	215	12/13	217
WALKER RIVER	7/8	221	7/8	234
COLORADO
GUNNISON RIVER BASIN	15/18	132	15/18	127
UPPER COLORADO RIVER BASIN	32/36	116	32/36	120
SOUTH PLATTE RIVER BASIN	21/22	94	21/22	102
LARAMIE AND NORTH PLATTE RIVER BASINS	12/12	110	12/12	115
YAMPA AND WHITE RIVER BASINS	20/22	108	21/22	121
ARKANSAS RIVER BASIN	11/11	71	11/11	79
UPPER RIO GRANDE BASIN	17/22	83	18/22	85
SAN MIGUEL, DOLORES, ANIMAS AND SAN JUAN RIVER BASINS	20/22	124	20/22	115
IDAHO
NORTHERN PANHANDLE REGION	10/10	102	9/10	128
COEUR D'ALENE-ST. JOE RIVER BASIN	7/7	115	7/7	113
CLEARWATER BASIN	16/16	108	15/16	113
SALMON BASIN	20/20	116	20/20	116
WEISER BASIN	4/4	122	4/4	117
PAYETTE BASIN	12/12	113	12/12	116
BOISE BASIN	10/11	118	10/11	126
BIG WOOD BASIN	8/9	140	8/9	134
LITTLE WOOD BASIN	4/5	159	4/5	188
BIG LOST BASIN	5/5	157	5/5	168
LITTLE LOST	3/3	137	3/3	154
BIRCH, MEDICINE LODGE, BEAVER, CAMAS BASINS	4/4	124	4/4	173
HENRYS FORK, TETON BASINS	8/8	100	8/8	114
SNAKE BASIN ABOVE PALISADES	21/21	98	21/21	111
WILLOW, BLACKFOOT, PORTNEUF BASINS	6/7	99	6/7	141
SNAKE BASIN ABOVE AMERICAN FALLS	29/29	99	29/29	117
RAFT BASIN	2/2	116	2/2	121
GOOSE CREEK BASIN	2/2	77	2/2	124
SALMON FALLS BASIN	4/6	81	4/6	122
BRUNEAU BASIN	5/8	88	5/8	126
OWYHEE BASIN	8/12	105	9/12	138
BEAR RIVER BASIN	21/21	102	21/21	131
MONTANA
KOOTENAI RIVER BASIN	8/8	118	8/8	138
FLATHEAD RIVER BASIN	14/17	111	14/17	129
UPPER CLARK FORK RIVER BASIN	14/14	93	14/14	105
BITTERROOT RIVER BASIN	8/8	94	8/8	106
LOWER CLARK FORK RIVER BASIN	9/9	114	9/9	117
JEFFERSON RIVER BASIN	19/21	92	19/21	116
MADISON RIVER BASIN	11/12	104	11/12	124
GALLATIN RIVER BASIN	7/7	94	7/7	110
MISSOURI HEADWATERS	31/31	96	31/31	115
HELENA VALLEY	4/4	75	4/4	91
SMITH, JUDITH, AND MUSSELSHELL RIVER BASINS	7/9	81	7/9	74
SUN, TETON AND MARIAS RIVER BASINS	5/6	106	5/6	118
MISSOURI MAINSTEM RIVER BASIN	18/21	89	18/21	91
ST. MARYS RIVER BASIN	2/2	117	2/2	154
MILK RIVER BASIN	1/1	90	1/1	73
UPPER YELLOWSTONE RIVER BASIN	21/22	88	21/22	95
WIND RIVER BASIN (WYOMING)	11/13	100	11/13	109
SHOSHONE RIVER BASIN (WYOMING)	6/6	85	6/6	92
BIGHORN RIVER BASIN (WYOMING)	24/26	91	24/26	101
TONGUE RIVER BASIN (WYOMING)	7/7	84	7/7	116
POWDER RIVER BASIN (WYOMING)	7/7	83	7/7	108
LOWER YELLOWSTONE RIVER BASIN	33/35	89	33/35	106
NEVADA
NORTHERN GREAT BASIN	7/8	158	7/8	159
SNAKE RIVER	7/11	84	7/11	126
OWYHEE RIVER	6/10	102	7/10	138
UPPER HUMBOLDT RIVER	9/17	109	10/17	139
LOWER HUMBOLDT RIVER	6/10	136	7/10	168
CLOVER VALLEY & FRANKLIN RIVER	5/7	113	5/7	139
EASTERN NEVADA BASINS	5/14	166	5/14	161
SOUTHERN NEVADA - Spring Mountains	3/3	229	3/3	186
NEW MEXICO
RIO CHAMA RIVER BASIN	4/5	118	4/5	100
UPPER RIO GRANDE BASIN - New Mexico	10/12	56	10/12	59
SANGRE DE CRISTO MOUNTAIN RANGE BASINS	10/11	46	10/11	57
JEMEZ RIVER BASIN	3/4	89	3/4	65
SAN FRANCISCO RIVER BASIN	6/6	48	5/6	49
GILA RIVER BASIN	3/3	25	3/3	36
MIMBRES RIVER BASIN	2/2	21	2/2	22
PECOS RIVER BASIN	3/3	54	3/3	51
SAN JUAN RIVER BASIN	13/13	116	13/13	111
ANIMAS RIVER BASIN	7/7	117	7/7	116
CANADIAN RIVER BASIN	6/7	39	6/7	53
ZUNI/BLUEWATER RIVER BASIN	1/1	133	1/1	112
RIO HONDO BASIN	1/1	11	1/1	19
CHUSKA MOUNTAINS	2/2	175	2/2	115
OREGON
OWYHEE	8/12	105	9/12	138
MALHEUR	3/3	87	3/3	85
GRANDE RONDE, POWDER, BURNT, IMNAHA	19/19	101	19/19	98
UMATILLA, WALLA WALLA, WILLOW	10/10	105	10/10	99
JOHN DAY	13/13	85	13/13	91
UPPER DESCHUTES, CROOKED	14/14	107	14/14	97
HOOD, SANDY, LOWER DESCHUTES	9/10	147	9/10	112
COAST RANGE	2/2	1817	2/2	132
WILLAMETTE	21/23	143	21/23	107
ROGUE, UMPQUA	12/13	132	12/13	96
KLAMATH	18/20	122	18/20	102
LAKE COUNTY, GOOSE LAKE	6/7	134	6/7	126
HARNEY	11/12	134	11/12	134
UTAH
RAFT RIVER	2/2	116	2/2	121
BEAR RIVER	25/26	102	25/26	131
WEBER-OGDEN RIVERS	20/23	92	20/23	123
PROVO R.-UTAH LAKE-JORDAN R.	19/26	100	19/26	132
TOOELE VALLEY-VERNON CREEK	3/4	91	3/4	116
NORTHEASTERN UINTAHS	11/13	128	11/13	134
DUCHESNE RIVER	14/15	144	14/15	150
PRICE-SAN RAFAEL	8/14	123	8/14	152
DIRTY DEVIL	5/9	107	5/9	141
SOUTH EASTERN UTAH	5/11	133	5/11	141
UPPER SEVIER RIVER	17/23	131	18/23	132
SAN PITCH RIVER	6/12	109	6/12	133
LOWER SEVIER RIVER	3/5	110	3/5	126
BEAVER RIVER	3/3	146	3/3	142
ESCALANTE RIVER	4/5	123	4/5	123
SOUTHWESTERN UTAH	10/13	172	10/13	159
WASHINGTON
SPOKANE	9/9	108	9/9	111
LOWER PEND OREILLE	5/5	96	5/5	119
UPPER COLUMBIA	7/9	107	7/9	133
CENTRAL COLUMBIA	11/11	100	11/11	120
UPPER YAKIMA	7/7	91	7/7	112
NACHES	8/8	96	7/8	116
LOWER YAKIMA	3/4	97	3/4	110
KLICKITAT	4/5	103	4/5	113
LOWER SNAKE, WALLA WALLA	14/14	100	14/14	98
LOWER COLUMBIA	15/17	120	14/17	128
SOUTH PUGET SOUND	13/14	104	12/14	118
CENTRAL PUGET SOUND	9/9	117	9/9	123
NORTH PUGET SOUND	12/13	109	11/13	137
OLYMPIC	4/4	100	4/4	120
WYOMING
SNAKE RIVER	22/22	97	22/22	110
MADISON HEADWATERS IN WYOMING	4/5	111	4/5	118
YELLOWSTONE HEADWATERS IN WYOMING	11/12	95	11/12	99
WIND RIVER	9/11	102	9/11	113
BIGHORN BASIN	11/11	85	11/11	97
SHOSHONE RIVER	6/6	85	6/6	92
POWDER RIVER	7/7	83	7/7	108
TONGUE RIVER	7/7	84	7/7	116
BELLE FOURCHE	3/3	52	3/3	102
CHEYENNE RIVER BASIN	2/2	57	2/2	90
UPPER N. PLATTE	19/20	108	19/20	116
SWEETWATER	2/3	87	3/3	104
LOWER N. PLATTE	4/4	55	4/4	110
LARAMIE RIVER	7/7	99	7/7	109
S. PLATTE	1/1	29	1/1	81
LITTLE SNAKE RIVER	8/9	113	8/9	125
UPPER GREEN RIVER	13/15	92	14/15	112
LOWER GREEN RIVER	10/12	107	10/12	128
UPPER BEAR RIVER	12/12	107	12/12	132

-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.