Wyoming water outlook – April, 2016
Reservoir storages across Wyoming increased to 115 to 125% above average for April due to wet March
by National Weather Service - Riverton WY
April 17, 2016
Synopsis: Wyoming had its 13th wettest March in the last 122 years with a statewide average of 1.91 inches of precipitation. This was 153 percent of the 20th century average. Most of this precipitation fell across the lower North Platte, Wind River, Sweetwater and lower Green River basin, eliminating most of the abnormally dry /d0/ and moderate /d1/ conditions that developed through the first part of 2016. Severe /d2/ drought remain over the Bighorn Range with moderate /d1/ drought across the far north and eastern Bighorn Basin, and across the western Wind River Range on the April 12th release of the drought monitor.
Summary of Impacts River and Streamflow Conditions: Slightly below normal snowmelt streamflow volumes (90 to 95 percent) are expected across almost all major basins across Wyoming. Slightly above normal streamflow volumes are expected across a majority of the Wind River Basin and portions of the Shoshone and upper North Platte watersheds. The Sweetwater, Powder and Tongue River basins are forecasted to have below to much below normal streamflow volumes during this upcoming snowmelt season. Reservoir storages across Wyoming increased to 115 to 125 percent above average for April.
Fire Weather Impacts: Though grasses were starting to green-up in the lower central basins, several agricultural burns have gotten out of control in early April where vegetation remains dry.
The significant wildland fire potential outlook through July 2016 shows a normal likelihood that significant wildland fires will occur. Significant wildland fires should be expected at typical times and intervals during normal significant wildland fire potential conditions.
Climate Summary: Below are the cumulative precipitation amounts from selected locations across west and central Wyoming for the current water year.
Note: Basin-wide percent of averages are based on 20th century (1901-2000) averages. Specific locations percent of averages are based on 1981-2010 normals.
Location Precipitation % Average and Drought (Inches) Condition Oct 2015-Mar 2016 ----------------------------------------------- Yellowstone Basin Avg, 14.50 inches, 119% Old Faithful, 11.02 inches, 82%
Snake Basin Avg, 20.04 inches, 98% Afton, 7.49 inches, 91% Moose, 14.11 inches, 110% Green And Bear Basin Avg, 6.52 inches, 99% Big Piney Airport, 2.23 inches, 104% Evanston Airport, 1.56 inches, 33% Fossil Butte N.M., 5.99 inches, 127% Green River, 5.61 inches, 179% Rock Springs Airport, 1.14 inches, 33% Rock Springs, 4.28 inches, 116%
Bighorn Basin Avg, 5.76 inches, 100% Cody, 3.76 inches, 129% Greybull Airport, 0.97 inches, 49% Powell Field Station, 1.43 inches, 95% Thermopolis, 5.49 inches, 131% Worland Airport, 2.29 inches, 107%
Powder/Tongue Basin Avg, 4.25 inches, 87% Buffalo Airport, 2.49 inches, 70% Kaycee, 2.28 inches, 69% Sheridan Airport, 5.19 inches, 109%
Lower Platte Basin Avg, 6.75 inches, 152% Casper Airport, 5.52 inches, 130% Cheyenne Airport, 7.32 inches, 190%
Wind River Basin Avg, 6.44 inches, 107% Dubois, 3.43 inches, 128% Lander Airport, 8.07 inches, 165% Riverton Airport, 4.22 inches, 152% Riverton (Downtown), 4.84 inches, 183%
Upper Platte Basin Avg, 6.22 inches, 115% Jeffrey City, 3.51 inches, 100%
Precipitation/Temperature Outlooks: Both the 30 day (April) and 90 day (April-June) outlooks showed an elevated chance of above normal temperatures across Wyoming, with the greatest chance across western Wyoming. The 90 day precipitation outlooks showed an elevated chance of above normal precipitation across most of Wyoming, except the northeast corner where there was no clear climate signal.
The seasonal drought outlook showed either improvement or removal of drought conditions by the end of June across north central Wyoming and the western Wind River Range. There were no areas of new drought development forecast in Wyoming through the end of June.
Hydrologic Summary and Outlook: Snowpack Data Drainage Basin, Snow Water Equivalent (SWE) % Change % of Median on April 14th since March 19th ----------------------------------------------- Snake River, 89%, - 9% Madison, 81%, -10% Yellowstone, 83%, - 5% Wind River, 90%, +10% Bighorn Basin, 73%, 0% Shoshone River, 79%, -12% Powder, 73%, + 5% Tongue, 60%, + 6% Upper Platte, 94%, - 3% Sweetwater, 83%, +11% Lower North Platte, 101%, +17% Laramie , 106%, - 6% South Platte, 125%, +10% Little Snake River, 87%, -12% Upper Green, 90%, -10% Lower Green, 92 %, - 9% Upper Bear, 79%, -18% -----------------------------------------------
Reservoir Data for April 14, 2016: Central Wyoming Boysen Reservoir, 79.7% Full Buffalo Bill Reservoir, 68.9% Full Bull Lake Reservoir, 47.4% Full Pathfinder Reservoir, 81.1% Full
Upper Green River Basin Big Sandy Reservoir, 60.0% Full Fontenelle Reservoir, 43.0% Full Flaming Gorge Reservoir, 85.0% Full
Upper Snake River Basin Grassy Lake Reservoir, 90.0% Full Jackson Lake Reservoir, 69.0% Full
Additional information on current drought conditions may be found at the following web addresses:
To report effects of the drought in your area, please go to the drought impact reporter at: http://droughtreporter.unl.edu/ and click on submit a report.
Information for the media may be found at: http://drought.unl.edu/newsoutreach/informationformedia.aspx
NWS Riverton Drought Page: http://www.weather.gov/riw/drought
Wind River Indian Reservation and Surrounding Area Climate and Drought Summaries: http://revampclimate.colostate.edu/revamp/project/wind-river
Drought-Preparedness - USGS Wyoming Drought Watch http://wy.water.usgs.gov/projects/drought/
U.S. Drought Monitor http://www.drought.gov
NOAA Drought Page http://www.drought.noaa.gov
Climate Prediction Center (CPC) http://www.cpc.ncep.noaa.gov
Additional River and Reservoir Information NWS Advanced Hydrologic Prediction Service (AHPS) http://www.water.gov/ahps2/index.php?wfo=riw
NRCS Wyoming http://www.wy.nrcs.usda.gov
USGS http://water.usgs.gov/
USBR http://www.usbr.gov/
Water Resource Data System (WRDS) http://www.wrds.uwyo.edu
Acknowledgments The drought monitor is a multi-agency effort involving NOAA’S National Weather Service and National Climatic Data Center, the USDA, State and Regional Center Climatologists and the National Drought Mitigation Center. Information for this statement has been gathered from NWS and FAA observation sites, state cooperative extension services, the USDA, USACE and USGS.
Questions or Comments For any questions or comments about this drought information statement, please contact: Arthur Meunier Climate/Drought Focal Point National Weather Service 12744 West US Highway 26 Riverton, WY 82501 Telephone 307-857-3898 800-211-1448 arthur.meunier@noaa.gov
|