National Weather Service United States Department of Commerce

Missouri Basin River Forecast Center
Water Supply Statement
Issued in cooperation with the Natural
Resources Conservation Service
Issued:  April 15, 2015

 

 

  

 Missouri River Basin Streamflow Fcst as of April 1, 2015   Missouri River Basin Mountain Snowpack as of April 1, 2015

 

Upper Missouri Basin

THE HIGH ELEVATION SNOW PACK IN THE UPPER MISSOURI BASIN AS OF
APRIL 1 WAS BELOW AVERAGE.  THE SNOW PACK ABOVE TOSTON,
MONTANA WAS 77 PERCENT OF AVERAGE.  THE SNOW PACK BETWEEN TOSTON
AND FORT PECK, MONTANA WAS 67 PERCENT.  THE SNOW PACK IN THE
ST MARY AND MILK RIVER BASINS WAS 53 PERCENT.
MARCH PRECIPITATION ACROSS THE UPPER MISSOURI BASIN RANGED FROM 
AVERAGE TO BELOW AVERAGE.  BASIN PRECIPITATION SUMMARIES FOR THE MISSOURI 
BASIN INCLUDE: MILK ST. MARY,  105 PERCENT; MILK CANADA, 86 PERCENT;
LOWER MILK, 112 PERCENT; ABOVE TOSTON, 38 PERCENT; TOSTON TO
FT. PECK, 53 PERCENT.

 

March 2015 Upper Missouri Mean Precip                     Oct-Mar WY2015 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 80 PERCENT OF AVERAGE APRIL-SEPTEMBER
FLOWS.  RUNOFF IS EXPECTED TO RANGE AROUND 55 PERCENT OF AVERAGE
FOR THE MISSOURI BASIN ABOVE FORT PECK, MONTANA.  
 


     Upper Missouri April 1, 2015 Spring and Summer Streamflow Forecasts

 

OF THE FOUR MAJOR IRRIGATION RESERVOIRS IN MONTANA: LIMA RESERVOIR
HAD 141 PERCENT AVERAGE STORAGE, CLARK CANYON WAS HOLDING 87 PERCENT OF
AVERAGE WATER, GIBSON RESERVOIR HAD 122 PERCENT OF AVERAGE STORED
WATER, AND FRESNO RESERVOIR HAD 152 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; 105 AND 118 PERCENT OF AVERAGE WATER, RESPECTIVELY.


Yellowstone Basin 

THE HIGH ELEVATION SNOW PACK IN THE YELLOWSTONE BASIN WAS BELOW AVERAGE
ON APRIL 1. THE SNOW PACK IN THE UPPER YELLOWSTONE BASIN WAS
78 PERCENT OF AVERAGE. THE SNOW PACKS IN THE WIND, BIGHORN, AND
SHOSHONE BASINS WERE 74, 91, AND 75 PERCENT OF AVERAGE,
RESPECTIVELY. THE SNOW PACKS IN THE TONGUE AND POWDER BASINS WERE
79 AND 91 PERCENT OF AVERAGE, RESPECTIVELY.


PRECIPITATION DURING MARCH WAS BELOW AVERAGE.  THE UPPER
YELLOWSTONE RIVER BASIN RECEIVED 38 PERCENT OF AVERAGE PRECIPITATION
WHILE THE LOWER YELLOWSTONE BASIN REPORTED 40 PERCENT OF AVERAGE.
THE BIGHORN BASIN RECEIVED 34 PERCENT OF AVERAGE PRECIPITATION
WHILE THE WIND RIVER BASIN RECEIVED 58 PERCENT OF AVERAGE.
THE LITTLE BIGHORN - UPPER TONGUE BASIN RECEIVED 34 PERCENT OF
AVERAGE AND THE POWDER RIVER HAD 38 PERCENT OF AVERAGE PRECIPITATION.



 March 2015 Yellowstone Mean Precip                    Oct-Mar WY2015 Yellowstone Mean Precip
 
FORECAST STREAM FLOW IN THE YELLOWSTONE BASIN IS BELOW
AVERAGE RANGE FOR THE UPCOMING SPRING AND SUMMER.  STREAM
FLOW FOR THE WIND-BIGHORN BASIN ABOVE ST. XAVIER, MONTANA IS
FORECAST TO BE ABOUT 55 PERCENT OF AVERAGE.  FLOW IN THE
TONGUE BASIN IS EXPECTED TO BE 70 PERCENT OF AVERAGE.  FLOWS IN THE
POWDER RIVER ARE EXPECTED TO BE ABOUT 70 PERCENT OF AVERAGE.
MONTHEND STORAGE AT BOYSEN RESERVOIR WAS 127 PERCENT OF AVERAGE.
STORED WATER IN BUFFALO BILL RESERVOIR WAS 137 PERCENT OF AVERAGE.
MONTHEND STORAGE WAS 108 PERCENT OF AVERAGE AT BIGHORN RESERVOIR.

 


     Yellowstone April 1, 2015 Spring and Summer Streamflow Forecasts

 

Platte Basin 

THE HIGH ELEVATION  SNOW PACK IN THE UPPER NORTH PLATTE BASIN WAS
69 PERCENT OF AVERAGE ON APRIL 1.  THE SNOW PACK IN THE NORTH
PLATTE  BASIN BELOW SEMINOE RESERVOIR WAS 59 PERCENT OF AVERAGE.
THE SNOW PACK IN THE SOUTH PLATTE BASIN WAS 82 PERCENT OF AVERAGE.
MARCH PRECIPITATION ACROSS THE PLATTE BASIN WAS BELOW  
AVERAGE. PRECIPITATION IN THE NORTH PLATTE BASIN ABOVE SEMINOE RESERVOIR 
WAS 78 PERCENT OF AVERAGE. IN THE NORTH PLATTE BASIN BETWEEN SEMINOE 
RESERVOIR AND GUERNSY RESERVOIR PRECIPITATION WAS 58 PERCENT OF AVERAGE. 
THE NORTH PLATTE BASIN BELOW GUERNSY RESERVOIR HAD 28 PERCENT OF AVERAGE 
PRECIPITATION.  THE HIGH ELEVATIONS OF THE SOUTH PLATTE BASIN HAD 55 
PERCENT OF AVERAGE PRECIPITATION WHEREAS THE PLAINS HAD 29 PERCENT OF AVERAGE
MARCH PRECIPITATION.




 

 March 2015 Platte Mean Precip                          Oct-Mar WY2015 Platte Mean Precip

 

STREAM FLOW IN THE PLATTE BASIN IS FORECAST TO BE BELOW 
AVERAGE DURING THE UPCOMING SPRING AND SUMMER.
RUNOFF FOR STREAMS ABOVE SEMINOE RESERVOIR ARE EXPECTED TO BE ABOUT
50 PERCENT OF AVERAGE.  STREAM FLOWS FOR THE NORTH PLATTE
BELOW SEMINOE RESERVOIR ARE FORECAST TO BE 35 PERCENT OF
AVERAGE. STREAMS IN THE SOUTH PLATTE BASIN ABOVE SOUTH PLATTE,
COLORADO CAN EXPECT 80 PERCENT OF AVERAGE FLOW. FOR THE
REMAINDER OF THE SOUTH PLATTE BASIN FLOWS ARE EXPECTED NEAR
85 PERCENT OF AVERAGE.
STORED WATER IN THE SOUTH PLATTE BASIN WAS 114 PERCENT OF AVERAGE
ON APRIL 1.  STORED WATER IN THE NORTH PLATTE BASIN WAS 101
PERCENT OF AVERAGE.

   North Platte Streamflow Fcst          South Platte Streamflow Fcst
 
PRECIPITATION MAPS
March 2015  WY 2015
March 2015 Precipitation Percent of 1981-2010 Average WY2015 Precipitation as Percent of 1981-2010 Average
March 2015 Basin Mean Precipitation          WY2015 Basin Mean Precipitation
March 2015 MBRFC Basin Mean Precipitation      WY2015 MBRFC Basin Mean Precipitation