United States Natural Resources Water and Climate Center Department of Conservation Portland, Oregon Agriculture Service S N O W - P R E C I P I T A T I O N U P D A T E Based on Mountain Data from NRCS SNOTEL Sites As of FRIDAY: APRIL 20 , 2018 ----------------------------------------------------------------------------- STATE PERCENT OF Normal RIVER BASIN Number Snow Water Accum of Sites Equivalent Precip ----------------------------------------------------------------------------- ALASKA ANCHORAGE/SHIP CREEK BASIN ................... 4 of 4 48 76 SUSITNA BASIN ................................ 3 of 5 103 117 NORTHERN KENAI MOUNTAINS ..................... 6 of 7 50 82 SOUTHERN KENAI ............................... 3 of 6 58 87 COPPER BASIN ................................. 2 of 3 82 108 PRINCE WILLIAM SOUND ......................... 1 of 7 * 91 CHENA BASIN .................................. 3 of 7 * * UPPER TANANA ................................. 2 of 5 * * KOYUKUK BASIN ................................ 2 of 6 * 109 CENTRAL YUKON BASIN .......................... 0 of 5 * 156 NORTON SOUND ................................. 0 of 4 * 135 KUPARUK-SAGAVANIRKTOK RIVER BASIN ............ 0 of 3 * 119 NORTHWEST ARCTIC RIVER BASIN ................. 0 of 1 * * SOUTHEAST ALASKA BASIN ....................... 1 of 3 * 74 ARIZONA VERDE RIVER BASIN ............................ 5 of 10 * 33 SAN FRANCISCO PEAKS .......................... 1 of 1 0 35 CENTRAL MOGOLLON RIM ......................... 3 of 4 0* 27 LITTLE COLORADO - SOUTHERN HEADWATERS ........ 5 of 6 0* 28 UPPER SALT RIVER BASIN / WHITE MOUNTAINS ..... 7 of 9 * 30 SAN FRANCISCO / UPPER GILA RIVER BASIN ....... 7 of 8 0* 37 CHUSKA MOUNTAINS ............................. 0 of 2 * * CALIFORNIA NORTHERN GREAT BASIN ......................... 4 of 5 82* 83 TRUCKEE RIVER ................................ 8 of 9 77 94 LAKE TAHOE ................................... 8 of 8 66 101 CARSON RIVER ................................. 8 of 9 81 90 WALKER RIVER ................................. 7 of 7 76 95 KLAMATH ...................................... 16 of 18 54* 82 COLORADO GUNNISON RIVER BASIN ......................... 13 of 16 53 60 UPPER COLORADO RIVER BASIN ................... 27 of 31 86 88 SOUTH PLATTE RIVER BASIN ..................... 16 of 22 91 102 LARAMIE AND NORTH PLATTE RIVER BASINS ........ 12 of 12 105 105 YAMPA AND WHITE RIVER BASINS ................. 19 of 20 92 86 ARKANSAS RIVER BASIN ......................... 6 of 9 63 68 UPPER RIO GRANDE BASIN ....................... 12 of 16 28 52 SAN MIGUEL, DOLORES, ANIMAS AND SAN JUAN RIVER BASIN .................. 17 of 19 31 46 IDAHO NORTHERN PANHANDLE REGION .................... 10 of 10 146 122 SPOKANE RIVER BASIN .......................... 10 of 10 143 120 CLEARWATER BASIN ............................. 15 of 16 150 124 SALMON BASIN ................................. 22 of 22 119 105 WEISER BASIN ................................. 4 of 4 81 92 PAYETTE BASIN ................................ 11 of 11 99 96 BOISE BASIN .................................. 9 of 10 93 99 BIG WOOD BASIN ............................... 8 of 9 105 99 LITTLE WOOD BASIN ............................ 5 of 5 92 98 BIG LOST BASIN ............................... 5 of 5 109 100 LITTLE LOST, BIRCH BASINS .................... 4 of 4 137 105 MEDICINE LODGE, BEAVER, CAMAS BASINS ......... 4 of 4 113 102 HENRYS FORK, TETON BASINS .................... 8 of 8 129 109 SNAKE BASIN ABOVE PALISADES .................. 18 of 18 138 113 WILLOW, BLACKFOOT, PORTNEUF BASINS ........... 5 of 6 103 99 SNAKE BASIN ABOVE AMERICAN FALLS ............. 28 of 29 132 110 RAFT BASIN ................................... 1 of 2 109 92 GOOSE CREEK BASIN ............................ 2 of 2 79 86 SALMON FALLS BASIN ........................... 5 of 5 75 89 BRUNEAU BASIN ................................ 5 of 5 68 93 OWYHEE BASIN ................................. 7 of 8 38 90 BEAR RIVER BASIN ............................. 14 of 15 94 88 MONTANA KOOTENAI RIVER BASIN ......................... 8 of 8 149 119 FLATHEAD RIVER BASIN ......................... 12 of 16 162 133 UPPER CLARK FORK RIVER BASIN ................. 13 of 15 174 134 BITTERROOT RIVER BASIN ....................... 7 of 7 173 125 LOWER CLARK FORK RIVER BASIN ................. 8 of 8 150 118 JEFFERSON RIVER BASIN ........................ 19 of 19 142 116 MADISON RIVER BASIN .......................... 11 of 11 130 113 GALLATIN RIVER BASIN ......................... 7 of 7 148 130 MISSOURI HEADWATERS .......................... 31 of 31 140 118 HEADWATERS MISSOURI MAINSTEM ................. 5 of 5 174 137 SMITH, JUDITH, AND MUSSELSHELL RIVER BASINS .. 9 of 10 152 118 SUN, TETON AND MARIAS RIVER BASINS ........... 3 of 6 185 137 MISSOURI MAINSTEM RIVER BASIN ................ 17 of 21 168 128 ST. MARY AND MILK RIVER BASINS ............... 3 of 3 170 127 UPPER YELLOWSTONE RIVER BASIN ................ 22 of 24 173 140 WIND RIVER BASIN (WYOMING) ................... 9 of 13 129 112 SHOSHONE RIVER BASIN (WYOMING) ............... 4 of 6 160 143 BIGHORN RIVER BASIN (WYOMING) ................ 14 of 16 146 129 TONGUE RIVER BASIN (WYOMING) ................. 6 of 7 118 87 POWDER RIVER BASIN (WYOMING) ................. 6 of 7 132 121 LOWER YELLOWSTONE RIVER BASIN ................ 28 of 35 134 113 NEVADA NORTHERN GREAT BASIN ......................... 7 of 9 76* 86 SNAKE RIVER .................................. 7 of 10 72 90 OWYHEE RIVER ................................. 5 of 5 50 94 UPPER HUMBOLDT RIVER ......................... 9 of 9 59 89 LOWER HUMBOLDT RIVER ......................... 5 of 9 53* 86 CLOVER VALLEY & FRANKLIN RIVER ............... 4 of 6 53 89 EASTERN NEVADA BASINS ........................ 4 of 4 45 65 NEW MEXICO RIO CHAMA RIVER BASIN ........................ 4 of 4 19 47 UPPER RIO GRANDE BASIN ....................... 9 of 9 32 50 SANGRE DE CRISTO MOUNTAIN RANGE BASINS ....... 9 of 11 0 43 JEMEZ RIVER BASIN ............................ 3 of 3 0* 31 SAN FRANCISCO RIVER BASIN .................... 3 of 3 0* 38 GILA RIVER BASIN ............................. 3 of 3 0* 42 MIMBRES RIVER BASIN .......................... 2 of 2 * 44 PECOS RIVER BASIN ............................ 1 of 1 0 26 SAN JUAN RIVER HEADWATERS .................... 5 of 5 36 48 ANIMAS RIVER BASIN ........................... 7 of 7 39 43 CIMARRON RIVER BASIN ......................... 2 of 2 0 41 ZUNI/BLUEWATER RIVER BASIN ................... 1 of 1 * 20 RIO HONDO BASIN .............................. 1 of 1 0* 79 CHUSKA MOUNTAINS ............................. 0 of 1 * * OREGON OWYHEE ....................................... 7 of 8 38 90 MALHEUR ...................................... 3 of 3 54* 85 GRANDE RONDE, POWDER, BURNT, IMNAHA .......... 15 of 17 101 107 UMATILLA, WALLA WALLA, WILLOW ................ 7 of 8 113* 111 JOHN DAY ..................................... 13 of 13 59 89 UPPER DESCHUTES, CROOKED ..................... 14 of 14 73 87 HOOD, SANDY, LOWER DESCHUTES ................. 7 of 8 110 106 COAST RANGE .................................. 1 of 2 * 106 WILLAMETTE ................................... 19 of 23 92 95 ROGUE, UMPQUA ................................ 12 of 12 60 81 KLAMATH ...................................... 16 of 18 54* 82 LAKE COUNTY, GOOSE LAKE ...................... 9 of 9 72* 86 HARNEY ....................................... 9 of 9 61* 79 UTAH RAFT RIVER ................................... 1 of 2 109 92 BEAR RIVER ................................... 17 of 24 94 87 WEBER-OGDEN RIVERS ........................... 17 of 20 59 71 PROVO R.-UTAH LAKE-JORDAN R. ................. 15 of 17 58 70 TOOELE VALLEY-VERNON CREEK ................... 3 of 4 51 64 NORTHEASTERN UINTAHS ......................... 6 of 10 75 77 DUCHESNE RIVER ............................... 12 of 13 63 66 PRICE-SAN RAFAEL ............................. 6 of 11 50 70 DIRTY DEVIL .................................. 3 of 6 5 66 SOUTH EASTERN UTAH ........................... 3 of 6 15 48 UPPER SEVIER RIVER ........................... 12 of 17 42* 63 SAN PITCH RIVER .............................. 5 of 11 * * LOWER SEVIER RIVER ........................... 1 of 3 * * BEAVER RIVER ................................. 2 of 2 33 53 ESCALANTE RIVER .............................. 3 of 4 3 55 SOUTHWESTERN UTAH ............................ 10 of 13 30* 53 WASHINGTON NORTHERN PANHANDLE ........................... 10 of 10 146 122 SPOKANE ...................................... 10 of 10 143 120 UPPER COLUMBIA ............................... 5 of 6 159 126 CENTRAL COLUMBIA ............................. 7 of 8 118 115 UPPER YAKIMA ................................. 4 of 5 111 112 LOWER YAKIMA ................................. 7 of 9 113 110 LOWER SNAKE .................................. 21 of 22 137 119 LOWER COLUMBIA ............................... 17 of 22 126 110 SOUTH PUGET SOUND ............................ 6 of 10 113* 120 CENTRAL PUGET SOUND .......................... 9 of 9 135 124 NORTH PUGET SOUND ............................ 7 of 12 132 116 OLYMPIC ...................................... 2 of 4 137 106 WYOMING SNAKE RIVER .................................. 19 of 20 136 112 MADISON-GALLATIN ............................. 5 of 5 129 113 YELLOWSTONE .................................. 13 of 13 174 139 WIND RIVER ................................... 9 of 12 129 112 BIGHORN BASIN ................................ 10 of 11 136 119 SHOSHONE RIVER ............................... 3 of 5 167 * POWDER RIVER ................................. 6 of 7 132 121 TONGUE RIVER ................................. 6 of 7 118 87 BELLE FOURCHE ................................ 1 of 1 350 115 CHEYENNE RIVER BASIN ......................... 2 of 2 160 98 UPPER N. PLATTE .............................. 16 of 18 97 95 SWEETWATER ................................... 3 of 3 84 * LOWER N. PLATTE .............................. 4 of 4 74 69 LARAMIE RIVER ................................ 6 of 6 116 107 S. PLATTE .................................... 2 of 3 138* 109 LITTLE SNAKE RIVER ........................... 8 of 8 84 82 UPPER GREEN RIVER ............................ 12 of 13 135 113 LOWER GREEN RIVER ............................ 7 of 11 96 83 UPPER BEAR RIVER ............................. 7 of 9 83 80 ----------------------------------------------------------------------------- The Snow Water Equivalent Percent of Median represents the snow water equivalent found at selected SNOTEL sites in or near the basin compared to the Median value for those sites on this day. The Accumulated Precipitation Percent of Average represents the total precipitation (beginning October 1st) found at selected SNOTEL sites in or near the basin compared to the Average value for those sites on this day. * = Data are not available or data may not provide a valid measure of conditions for over half of the sites within the basin. Refer to the individual state reports for a complete data listing and basin analysis. Units = inches for the Current and Normal Snow Water Equivalent and Total Precipitation values Medians and averages are calculated for the period 1981-2010. 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 for the day is less than 10% of the maximum median value for the year. * Basin - More than half of the sites within the basin are flagged with *, preventing the calculation of a meaningful basin index. The basin index is calculated as the sum of the valid current values divided by the sum of the corresponding medians (for snow water equivalent) or averages (for precipitation) and the resulting fraction multiplied by 100.