January 1, 2010 Spring and Summer Streamflow Forecasts
Missouri River Basin Streamflow Forecast Missouri River Basin Mountain Snowpack
Upper Missouri Basin
THE HIGH ELEVATION SNOW PACK IN THE UPPER MISSOURI BASIN AS OF
JANUARY 1 WAS MAINLY AVERAGE TO SLIGHTLY BELOW AVERAGE. THE SNOW
PACK ABOVE TOSTON, MONTANA WAS 77 PERCENT OF AVERAGE. THE SNOW
PACK BETWEEN TOSTON AND FORT PECK, MONTANA WAS 95 PERCENT. THE
SNOW PACK IN THE ST MARY AND MILK RIVER BASINS WAS 63 PERCENT.
FALL PRECIPITATION ACROSS THE UPPER MISSOURI BASIN WAS ABOVE AVERAGE.
BASIN PRECIPITATION SUMMARIES FOR THE MISSOURI BASIN
INCLUDE: MILK ST. MARY, 118 PERCENT; MILK CANADA, 169 PERCENT;
LOWER MILK, 121 PERCENT; ABOVE TOSTON, 101 PERCENT; TOSTON TO
FT. PECK, 137 PERCENT.
December 2009 Upper Missouri Mean Precip Oct-Dec WY2010 Upper Missouri Mean Precip
STREAM FLOW IN THE UPPER MISSOURI BASIN IS FORECAST TO BE BELOW AVERAGE
DURING THE UPCOMING SPRING AND SUMMER. THE ST. MARY RIVER IS FORECAST
TO HAVE 88 PERCENT OF AVERAGE APRIL-SEPTEMBER FLOWS. RUNOFF IS
EXPECTED TO RANGE AROUND 73 PERCENT OF AVERAGE FOR THE MISSOURI BASIN
ABOVE FORT PECK, MONTANA. FORECASTS FOR THE MILK RIVER BASIN CALL FOR
AROUND 77 PERCENT OF AVERAGE SPRING-SUMMER RUNOFF.
Upper Missouri January 1, 2010 Spring and Summer Streamflow Forecasts
OF THE FOUR MAJOR IRRIGATION RESERVOIRS IN MONTANA: LIMA RESERVOIR
HAD 121 PERCENT AVERAGE STORAGE, CLARK CANYON WAS HOLDING 111 PERCENT OF
AVERAGE WATER, GIBSON RESERVOIR HAD 34 PERCENT OF AVERAGE STORED
WATER, AND FRESNO RESERVOIR HAD 75 PERCENT OF AVERAGE STORED WATER.
THE MAJOR HYDROELECTRIC RESERVOIRS IN MONTANA (CANYON FERRY AND
FORT PECK) HAD MONTHEND STORAGE IN THE AVERAGE TO BELOW AVERAGE
RANGE; 97 AND 85 PERCENT OF AVERAGE WATER, RESPECTIVELY.
Yellowstone Basin
THE HIGH ELEVATION SNOW PACK IN THE YELLOWSTONE BASIN WAS AVERAGE
TO BELOW AVERAGE ON JANUARY 1. THE SNOW PACK IN THE UPPER
YELLOWSTONE BASIN WAS 97 PERCENT OF AVERAGE. THE SNOW PACKS IN THE
WIND, BIGHORN, AND SHOSHONE BASINS WERE 95, 79, AND 69 PERCENT OF
AVERAGE, RESPECTIVELY. THE SNOW PACKS IN THE TONGUE AND POWDER
BASINS WERE 82 AND 85 PERCENT OF AVERAGE, RESPECTIVELY.
PRECIPITATION DURING OCTOBER THROUGH DECEMBER WAS AT OR ABOVE
AVERAGE. THE UPPER YELLOWSTONE RIVER BASIN RECEIVED 96 PERCENT
OF AVERAGE PRECIPITATION WHILE THE LOWER YELLOWSTONE BASIN REPORTED
125 PERCENT OF AVERAGE. THE BIGHORN BASIN RECEIVED 86 PERCENT OF
AVERAGE PRECIPITATION WHILE THE WIND RIVER BASIN RECEIVED 108 PERCENT
OF AVERAGE. THE LITTLE BIGHORN - UPPER TONGUE BASIN RECEIVED
91 PERCENT OF AVERAGE AND THE POWDER RIVER HAD 108 PERCENT OF
AVERAGE PRECIPITATION.
FORECAST STREAM FLOW IN THE YELLOWSTONE BASIN IS IN THE BELOW
AVERAGE RANGE FOR THE UPCOMING SPRING AND SUMMER. RUNOFF AT
BILLINGS, MONTANA IS EXPECTED TO BE 67 PERCENT OF AVERAGE, WITH
A PROBABLE RANGE BETWEEN 41 AND 93 PERCENT OF AVERAGE. STREAM
FLOW FOR THE WIND-BIGHORN BASIN ABOVE ST. XAVIER, MONTANA IS
FORECAST TO BE ABOUT 57 PERCENT OF AVERAGE WITH A PROBABLE RANGE
OF 31 TO 83 PERCENT OF AVERAGE FLOW. FLOW IN THE
TONGUE BASIN IS EXPECTED TO BE 66 PERCENT OF AVERAGE WITH
A REASONABLY LIKELY RANGE OF 18 TO 112 PERCENT OF AVERAGE FLOW.
FLOWS IN THE POWDER RIVER ARE EXPECTED TO BE ABOUT 50 PERCENT OF
AVERAGE WITH A REASONABLY LIKELY RANGE OF 21 TO 110 PERCENT OF
AVERAGE.
Yellowstone January 1, 2010 Spring and Summer Streamflow Forecasts
MONTHEND STORAGE AT BOYSEN RESERVOIR WAS 96 PERCENT OF AVERAGE.
STORED WATER IN BUFFALO BILL RESERVOIR WAS 107 PERCENT OF AVERAGE.
MONTHEND STORAGE WAS 107 PERCENT OF AVERAGE AT BIGHORN RESERVOIR.
Platte Basin
THE HIGH ELEVATION SNOW PACK IN THE UPPER NORTH PLATTE BASIN WAS
89 PERCENT OF AVERAGE ON JANUARY 1. THE SNOW PACK IN THE NORTH
PLATTE BASIN BELOW SEMINOE RESERVOIR WAS 98 PERCENT OF AVERAGE.
THE SNOW PACK IN THE SOUTH PLATTE BASIN WAS 93 PERCENT OF AVERAGE.
FALL PRECIPITATION ACROSS THE PLATTE BASIN WAS ABOVE AVERAGE.
PRECIPITATION FROM OCTOBER THROUGH DECEMBER IN THE NORTH PLATTE
BASIN ABOVE SEMINOE RESERVOIR WAS 114 PERCENT OF AVERAGE. IN THE
NORTH PLATTE BASIN BETWEEN SEMINOE RESERVOIR AND GUERNSY RESERVOIR
PRECIPITATION WAS 124 PERCENT OF AVERAGE. THE NORTH PLATTE BASIN
BELOW GUERNSY RESERVOIR HAD 181 PERCENT OF AVERAGE PRECIPITATION.
THE HIGH ELEVATIONS OF THE SOUTH PLATTE BASIN HAD 125 PERCENT OF
AVERAGE PRECIPITATION WHEREAS THE PLAINS HAD 160 PERCENT OF AVERAGE
OCTOBER-DECEMBER PRECIPITATION.
December 2009 Platte Mean Precip Oct-Dec WY2010 Platte Mean Precip
STREAM FLOW IN THE PLATTE BASIN IS FORECAST TO RANGE FROM BELOW
AVERAGE TO AVERAGE DURING THE UPCOMING SPRING AND SUMMER.
RUNOFF FOR STREAMS ABOVE SEMINOE RESERVOIR ARE EXPECTED TO BE ABOUT
75 TO 95 PERCENT OF AVERAGE. STREAM FLOWS FOR THE NORTH PLATTE
BELOW SEMINOE RESERVOIR ARE FORECAST TO BE 80 TO 105 PERCENT OF
AVERAGE. STREAMS IN THE SOUTH PLATTE BASIN ABOVE SOUTH PLATTE,
COLORADO CAN EXPECT 70 TO 90 PERCENT OF AVERAGE FLOW. FOR THE
REMAINDER OF THE SOUTH PLATTE BASIN FLOWS ARE EXPECTED TO
BE ABOUT 80 TO 90 PERCENT OF AVERAGE.
STORED WATER IN THE SOUTH PLATTE BASIN WAS 100 PERCENT OF AVERAGE
ON JANUARY 1.
North Platte Streamflow Fcst South Platte Streamflow Fcst
