Missouri Basin River Forecast Center
Water Supply Statement
Issued in cooperation with the Natural
Resources Conservation Service
Issued:  August 11, 2006

Most of the Missouri River Basin reported  below average  precipitation
during the month of July, with the exception of the South Platte
basin where above average precipitation fell.  Also,  streamflow
data indicates the flows for the month of July were below average.

Precipitation in the Missouri River Basin during July ranged from below
average to above average, with the northern portion of the basin
reporting below average precipitation.  Precipitation in Montana was
generally below average, with amounts  ranging from a 0 percent of
average (0.0 in.) at several locations across the state to 152 percent of
average (3.20 in.) at Monument Park,  Montana.  Precipitation
in Wyoming was generaly below average with reports ranging from
0 percent of average (0.00 in.) at several locations across the state
to 232 percent of average (2.11 in.) at Alcova 14 mi SW,  Wyoming.
Precipitation in northeastern Colorado was generally above average,
with reports ranging from 35 percent of average (0.60 in.)  at
Trapper Lake, Colorado to 356  percent  of  average   (5.70 in.)
at Porphyry Lake, Colorado.

Basin precipitation summaries for the Missouri Basin:

Basin               Average Precipitation
Milk St. Mary              31%
Milk Canada                13%
Above Toston               65%
Toston to Ft. Peck         32%
Lower Milk                 24%
Upper Yellowstone          58%
Wind River                 40%
Bighorn                    41%
Little Bighorn Tongue      34%
Powder                     44%
Lower Yellowstone          30%
Upper North Platte        108%
Lower North Platte         85%
South Platte Mountains    169%
South Platte Plains       106%

July 2006 Basin Mean Precipitation


Stored water in the South Platte Basin as of August 1 was 76 percent of average for this time of the year. Of the four major irrigation reservoirs in Montana, Lima Reservoir had 134 percent average storage; Clark Canyon was holding 53 percent of average water, Gibson Reservoir had 46 percent of average stored water and Fresno Reservoir had 79 percent of average stored water. Of the three major hydroelectric reservoirs in Montana, Canyon Ferry and Fort Peck had monthend storage in the average range; 98 and 58 percent of average water, respectively. Bighorn reservoir was holding 74 percent of average stored water. Runoff during July, as indicated by U.S. Geological Survey long term gaging stations, was below average. The Marias River near Shelby, Montana had 42 percent of average runoff. The Yellowstone River was estimated to have had 63 percent of average runoff at Corwin Springs, while at Billings, Montana runoff was 47 percent of average.

          Precipitation Maps

          July 2006        Oct-July WY 2006


July 2006 Precipitation Percent of 1971-2000 Average  Oct-Jul  WY2006 Precipitation as Percent of 1971-2000 Average

July 2006 Basin Mean Precipitation                    Oct-Jul WY2006 Basin Mean Precipitation


July 2006 MBRFC Basin Mean Precipitation              Oct-Jul WY2006 MBRFC Basin Mean Precipitation




















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