NWS Missouri River Basin/Pleasant Hill, MO

Missouri Basin River Forecast Center
Water Supply Statement
Issued in cooperation with the Natural
Resources Conservation Service
Issued:  June 11, 2008

           June 1, 2008 Spring and Summer Streamflow Forecasts

Upper Missouri Basin

MAY PRECIPITATION WAS ABOVE AVERAGE ACROSS MOST OF THE UPPER MISSOURI
BASIN.  ABOVE TOSTON, MILK ST. MARY AND CANADA WERE NEAR AVERAGE. BASIN
PRECIPITATION SUMMARIES FOR THE MISSOURI BASIN INCLUDE: MILK ST. MARY,
162 PERCENT; MILK CANADA, 153 PERCENT; LOWER MILK, 134 PERCENT; ABOVE TOSTON,
114 PERCENT; TOSTON TO FT. PECK, 194 PERCENT.

May 2008 Upper Missouri Mean Precip                     Oct-May WY2008 Upper Missouri Mean Precip

STREAM FLOW IN THE UPPER MISSOURI BASIN IS FORECAST TO BE ABOVE AVERAGE
DURING THE UPCOMING SUMMER.  THE ST. MARY RIVER IS FORECAST TO
HAVE 108 PERCENT OF AVERAGE JUNE-SEPTEMBER FLOWS.  RUNOFF IS EXPECTED TO
RANGE AROUND 120 PERCENT OF AVERAGE FOR THE MISSOURI BASIN ABOVE FORT
PECK, MONTANA.  FORECASTS FOR THE MILK RIVER BASIN CALL FOR AROUND 130
PERCENT OF AVERAGE SPRING SUMMER RUNOFF. 
  

     Upper Missouri June 1, 2008 Spring and Summer Streamflow Forecasts

OF THE FOUR MAJOR IRRIGATION RESERVOIRS IN MONTANA: LIMA RESERVOIR

HAD 99 PERCENT AVERAGE STORAGE, CLARK CANYON WAS HOLDING 75 PERCENT OF

AVERAGE WATER, GIBSON RESERVOIR HAD 94 PERCENT OF AVERAGE STORED
WATER, AND FRESNO RESERVOIR HAD 72 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; 102 AND 55 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 159 PERCENT OF

AVERAGE RUNOFF IN MAY.

Yellowstone Basin

PRECIPITATION DURING THE MONTH OF MAY WAS ABOUT 195 PERCENT OF
AVERAGE IN THE WIND RIVER BASIN ABOVE BOYSEN RESERVOIR, 169 PERCENT
OF AVERAGE IN THE UPPER YELLOWSTONE BASIN, 190 PERCENT OF AVERAGE
IN THE BIGHORN BASIN, AND 199 PERCENT OF AVERAGE IN THE LITTLE
BIGHORN BASINS-UPPER TONGUE BASINS, 244 PERCENT OF AVERAGE IN THE
POWDER RIVER BASIN, AND 204 PERCENT OF AVERAGE IN THE LOWER
YELLOWSTONE BASIN.

  May 2008 Yellowstone Mean Precip                    Oct-May WY2008 Yellowstone Mean Precip

 

STREAM FLOW IN MOST OF THE YELLOWSTONE BASIN IS FORECAST TO BE
ABOVE AVERAGE DURING THE UPCOMING SUMMER.  RUNOFF AT BILLINGS,
MONTANA IS EXPECTED TO BE 122 PERCENT OF AVERAGE.  RUNOFF IN
THE WIND-BIGHORN BASIN ABOVE ST. XAVIER, MONTANA IS FORECAST
TO BE ABOUT 119 PERCENT OF AVERAGE.

FLOW IN THE TONGUE BASIN IS NORMALLY NOT FORECAST IN JUNE BECAUSE
THE STATISTICAL METHODOLOGY USED HAS A PRIMARY DEPENDENCY ON SNOWPACK,
WHILE FROM JUNE THROUGH SEPTEMBER TONGUE RIVER RUNOFF IS MORE
CLOSELY RELATED TO RAINFALL.  THIS YEAR, THOUGH, THE ABOVE-NORMAL
SNOWPACK RESULTED IN A FORECAST OF 118 PERCENT OF AVERAGE AT THE
TONGUE RIVER RESERVOIR. 

 

     Yellowstone June 1, 2008 Spring and Summer Streamflow Forecasts

 

MONTH END STORAGE WAS AT 84 PERCENT OF AVERAGE AT BOYSEN RESERVOIR
IN WYOMING, 121 PERCENT OF AVERAGE AT BUFFALO BILL RESERVOIR IN
WYOMING, AND 105 PERCENT OF AVERAGE AT BIGHORN RESERVOIR ON THE
WYOMING/MONTANA BORDER.

RUNOFF DURING MAY IN THE YELLOWSTONE RIVER WAS 106 PERCENT
OF THE 1971 TO 2000 AVERAGE AT CORWIN SPRINGS, MONTANA AND 92
PERCENT OF THAT AVERAGE AT BILLINGS, MONTANA.

 

Platte Basin

PRECIPITATION DURING MAY IN THE PLATTE BASIN RANGED FROM BELOW
AVERAGE TO AVERAGE. MAY PRECIPITATION IN THE NORTH PLATTE BASIN
ABOVE SEMINOE RESERVOIR WAS 1113 PERCENT OF AVERAGE. IN THE
NORTH PLATTE BASIN BETWEEN SEMINOE RESERVOIR AND GUERNSY
RESERVOIR PRECIPITATION WAS 181 PERCENT OF AVERAGE. THE NORTH
PLATTE BASIN BELOW GUERNSY RESERVOIR HAD 128 PERCENT OF AVERAGE
PRECIPITATION. THE HIGH ELEVATIONS OF THE SOUTH PLATTE BASIN HAD
87 PERCENT OF AVERAGE MAY PRECIPITATION WHEREAS THE PLAINS
HAD 59 PERCENT OF AVERAGE PRECIPITATION.
 

May 2008 Platte Mean Precip                          Oct-May WY2008 Platte Mean Precip

Stream flow in the Platte basin is forecast to range from below

average to above average during the upcoming spring and summer.
Runoff for streams above Seminoe Reservoir are expected to be about
110 to 125 percent of average.  Stream flows for the North  Platte
below Seminoe Reservoir are forecast to be 60 to 110 percent of
average. The South Platte Basin above South Platte, Colorado can
expect about 100 to 110 percent of average flow.  For the remainder
of the South Platte Basin flows are expected to be about 80 to
110 average.

 

North Platte Streamflow Fcst          South Platte Streamflow Fcst

STORED WATER IN THE NORTH PLATTE BASIN AS OF JUNE 1 WAS 63 PERCENT

OF AVERAGE. IN THE SOUTH PLATTE BASIN STORED WATER WAS 84 PERCENT OF
AVERAGE.

PRECIPITATION MAPS

May 2008	WY 2008
May 2008 Precipitation Percent of 1971-2000 Average	WY2008 Precipitation as Percent of 1971-2000 Average
May 2008 Basin Mean Precipitation	WY2008 Basin Mean Precipitation
May 2008 MBRFC Basin Mean Precipitation	WY2008 MBRFC Basin Mean Precipitation