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
FEBRUARY 1 WAS BELOW AVERAGE. THE SNOW PACK ABOVE
TOSTON, MONTANA WAS 70 PERCENT OF AVERAGE. THE SNOW PACK
BETWEEN TOSTON AND FORT PECK, MONTANA WAS 83 PERCENT. THE
SNOW PACK IN THE ST MARY AND MILK RIVER BASINS WAS 83 PERCENT.
JANUARY PRECIPITATION WAS MAINLY BELOW AVERAGE ACROSS
THE UPPER MISSOURI BASIN. BASIN PRECIPITATION SUMMARIES FOR THE
MISSOURI BASIN INCLUDE: MILK ST. MARY, 72 PERCENT; MILK CANADA, 124
PERCENT; LOWER MILK, 43 PERCENT; ABOVE TOSTON, 48 PERCENT; TOSTON
TO FT. PECK, 44 PERCENT.
January 2007 Upper Missouri Mean Precip Oct-Jan WY2007 Upper Missouri Mean Precip
STREAM FLOW IN THE UPPER MISSOURI BASIN IS FORECAST TO BE AVERAGE
TO SLIGHTLY BELOW AVERAGE DURING THE UPCOMING SPRING AND SUMMER.
THE ST. MARY RIVER IS FORECAST TO HAVE 94 PERCENT OF AVERAGE
APRIL-SEPTEMBER FLOWS. RUNOFF IS EXPECTED TO RANGE AROUND 78
PERCENT OF AVERAGE FOR THE MISSOURI BASIN ABOVE FORT PECK, MONTANA.
FORECASTS FOR THE MILK RIVER BASIN CALL FOR AROUND 87 PERCENT OF
AVERAGE SPRING SUMMER RUNOFF.
OF THE FOUR MAJOR IRRIGATION RESERVOIRS IN MONTANA: LIMA RESERVOIR
HAD 126 PERCENT AVERAGE STORAGE, CLARK CANYON WAS HOLDING 79 PERCENT
OF AVERAGE WATER, GIBSON RESERVOIR HAD 96 PERCENT OF AVERAGE STORED
WATER, AND FRESNO RESERVOIR HAD 79 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; 95 AND 56 PERCENT OF AVERAGE WATER, RESPECTIVELY.
AS INDICATED BY THE U.S. GEOLOGICAL LONG TERM GAGING STATIONS,
THE MARIAS RIVER NEAR SHELBY, MONTANA HAD AN ESTIMATED 64 PERCENT
OF AVERAGE RUNOFF IN JANUARY.
Yellowstone Basin
THE HIGH ELEVATION SNOW PACK IN THE YELLOWSTONE BASIN WAS BELOW
AVERAGE ON FEBRUARY 1. THE SNOW PACK IN THE UPPER YELLOWSTONE
BASIN WAS 70 PERCENT OF AVERAGE. THE SNOW PACKS IN THE WIND,
BIGHORN, AND SHOSHONE BASINS WERE 72, 73, AND 66 PERCENT OF
AVERAGE, RESPECTIVELY. THE SNOW PACKS IN THE TONGUE AND POWDER
BASINS WERE 84 AND 70 PERCENT OF AVERAGE, RESPECTIVELY.
WITH THE EXCEPTION OF WIND AND BIGHORN BASINS, PRECIPITATION
DURING THE MONTH OF JANUARY WAS BELOW AVERAGE TO MUCH BELOW
AVERAGE. THE RANGE WAS FROM 113 PERCENT OF AVERAGE IN THE WIND
RIVER BASIN TO 31 PERCENT OF AVERAGE IN THE LOWER YELLOWSTONE
BASIN. FOR THE WATER YEAR BEGINNING IN OCTOBER, PRECIPITATION FOR
THE BASIN AS A WHOLE IS NEARER AVERAGE, THOUGH THE POWDER RIVER
BASIN HAS RECEIVED BUT 64 PERCENT OF AVERAGE PRECIPITATION SINCE
OCTOBER 1.
STREAM FLOW IN THE YELLOWSTONE BASIN IS FORECAST TO BE AVERAGE TO
BELOW AVERAGE DURING THE UPCOMING SPRING AND SUMMER. RUNOFF AT
BILLINGS, MONTANA IS EXPECTED TO BE 85 PERCENT OF AVERAGE, WITH
A PROBABLE RANGE BETWEEN 58 AND 111 PERCENT OF AVERAGE. STREAM
FLOW FOR THE WIND-BIGHORN BASIN ABOVE ST. XAVIER, MONTANA IS
FORECAST TO BE 70 PERCENT OF AVERAGE WITH A PROBABLE RANGE
OF 44 TO 153 PERCENT OF AVERAGE FLOW IN SUB-BASINS. FLOW IN THE
TONGUE BASIN IS EXPECTED TO BE 75 TO 83 PERCENT OF AVERAGE WITH
A REASONABLY LIKELY RANGE OF 36 TO 114 PERCENT OF AVERAGE FLOW.
FLOWS IN THE POWDER RIVER ARE EXPECTED TO BE ABOUT 49 PERCENT OF
AVERAGE WITH A REASONABLY LIKELY RANGE OF 6 TO 94 PERCENT.
MONTHEND STORAGE WAS 71 PERCENT OF AVERAGE AT BOYSEN RESERVOIR IN
WYOMING, 107 PERCENT OF AVERAGE AT BUFFALO BILL RESERVOIR IN
WYOMING, AND 90 PERCENT OF AVERAGE AT BIGHORN RESERVOIR ON THE
WYOMING/MONTANA BORDER.
RUNOFF DURING JANUARY IN THE YELLOWSTONE RIVER WAS 95 PERCENT OF
THE 1971 TO 2000 AVERAGE AT CORWIN SPRINGS AND 84 PERCENT OF THAT
PERIOD`S AVERAGE AT BILLINGS.
(HTTP:/MT.WATER.USGS.GOV/PUB/NWC.RELEASE.HTML).
Platte Basin
THE HIGH ELEVATION SNOW PACK IN THE UPPER NORTH PLATTE BASIN WAS
76 PERCENT OF AVERAGE. THE SNOW PACK IN THE NORTH PLATTE BASIN
BELOW SEMINOE RESERVOIR WAS 84 PERCENT OF AVERAGE. THE SNOW PACK
IN THE SOUTH PLATTE BASIN WAS 113 PERCENT.
PRECIPITATION ACROSS THE PLATTE BASIN WAS ABOVE AVERAGE TO ABOVE
AVERAGE FOR THE MONTH OF JANUARY PRECIPITATION IN NORTH PLATTE BASIN
ABOVE SEMINOE RESERVOIR WAS 88 PERCENT AVERAGE. IN THE NORTH
PLATTE BASIN BETWEEN SEMINOE RESERVOIR AND GUERNSY RESERVOIR
PRECIPITATION WAS 93 PERCENT OF AVERAGE. THE NORTH PLATTE BASIN BELOW
GUERNSY RESERVOIR HAD 56 PERCENT OF AVERAGE PRECIPITATION. THE
HIGH ELEVATIONS OF THE SOUTH PLATTE BASIN HAD 173 PERCENT OF AVERAGE
PRECIPITATION WHEREAS THE PLAINS HAD 128 PERCENT OF AVERAGE
PRECIPITATION.
January 2007 Platte Mean Precip Oct-Jan WY2007 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 85
PERCENT OF AVERAGE. STREAM FLOW FOR THE NORTH PLATTE BELOW SEMINOE
RESERVOIR ARE FORECAST TO BE BETWEEN 60 TO 80 PERCENT OF AVERAGE.
HOWEVER THE LARAMIE RIVER IS FORECAST TO HAVE AVERAGE RUNOFF. THE
SOUTH PLATTE BASIN ABOVE SOUTH PLATTE, COLORADO CAN EXPECT ABOUT
BETWEEN 100 AND 110 PERCENT OF AVERAGE FLOW. FOR THE REMAINDER OF
THE SOUTH SLATTE BASIN FLOWS ARE EXPECTED TO BE BETWEEN 95 AND
110 PERCENT OF AVERAGE.
STORED WATER IN THE NORTH PLATTE BASIN AS OF FEBRUARY 1 WAS 52
PERCENT OF AVERAGE. THE SOUTH PLATTE BASIN HAD 83 PERCENT OF
AVERAGE STORED WATER.