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:  February 20, 2020

 

 

                   February 1, 2020 Spring and Summer Streamflow Forecasts

 

 Upper Missouri Basin


The high elevation snow pack in the Upper Missouri Basin as of February 1
was near to above ave
rage. The snow pack above Fort Peck, Montana was
108 percent. The snow pack in the St. Mary Basin was 123 percent, and the
Milk River Basin was 150 percent.

January precipitation across the Upper Missouri Basin was below average.
Basin precipitation summaries for the Missouri Basin include: Milk St. Mary,
71 percent; Milk Canada, 38 percent; Lower Milk, 75 percent; above Toston,
95 percent; Toston to Ft. Peck, 65 percent. 

 

January 2020 Upper Missouri Mean Precip            Oct-Jan WY2020 Upper Missouri Mean Precip


Stream flow in the Upper Missouri Basin is forecast to be
near average during the upcoming Spring and Summer.
The St. Mary River is forecast to have 100 percent of average
April-September flows. Runoff is expected to range around
10. percent of average for the Missouri Basin above Fort Peck,
Montana.


 


  Upper Missouri February 1, 2020 Spring and Summer Streamflow Forecasts

 

Of the four major irrigation reservoirs in Montana; Lima
Reservoir had 166 percent average storage, Clark Canyon was
holding 118 percent of average water, Gibson Reservoir had 48
percent of average stored water, and Fresno Reservoir had
147 percent of average stored water.

The major hydroelectric reservoirs in Montana (Canyon Ferry and
Fort Peck), had monthend storage in the average to above
average range; 100 and 118 percent of average water, respectively
.



Yellowstone Basin 

The high elevation snow pack in the Yellowstone Basin was above average
on February 1. The snow pack in the Upper Yellowstone Basin was 104 percent
of average. The snow packs in the Wind, Bighorn, and Shoshone Basins were 97,
120, and 103 percent of average, respectively. The snow packs in the Tongue
and Powder basins were 101 and 120 percent of average, respectively.

Precipitation during January was below average. The upper Yellowstone
River Basin received 82 percent of average precipitation while the
Lower Yellowstone River Basin reported 71 percent of average. The
Bighorn Basin received 73 percent of average precipitation while the
Wind River Basin received 82 percent of average. The Little Bighorn -
Upper Tongue Basin received 82 percent of average and the Powder River
had 84 percent of average precipitation.




 January 2020 Yellowstone Mean Precip                 Oct-Jan WY2020 Yellowstone Mean Precip
 

Forecast stream flow in the Yellowstone Basin is near average 
for the upcoming Spring and Summer.  Stream flow for the
Yellowstone River above Sidney, Montana is forecast to be about 
119 percent of average.  Flow in the Tongue Basin is expected to be
120 percent of average.  Flows in the Powder River are expected
to be about 145 percent of average.

Monthend storage at Boysen Reservoir was 113 percent of average. 
Stored water in Buffalo Bill Reservoir was 133 percent of average. 
Monthend storage was 106 percent of average at Bighorn Reservoir.

 


    Yellowstone February 1, 2020 Spring and Summer Streamflow Forecasts

 

Platte Basin 

The high elevation snow pack in the Upper North Platte Basin was
100 percent of average on February 1.  The snow pack in the North Platte
Basin below Seminoe Reservoir was 112 percent of average.  The snow
pack in the South Platte Basin was 119 percent of average.

Precipitation during January in the Upper North Platte Basin was 114
percent of average.  In the Lower North Platte Basin, precipitation
was 93 percent of average.  The North Platte Plains below Guernsy
Reservoir had 52 percent.  The South Platte Mountains had 34
percent whereas the Plains had 30 percent of average January
precipitation.





 

 January 2020 Platte Mean Precip                          Oct-Jan WY2020 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 105 percent of average. Streams in the South Platte
Basin above South Platte, Colorado can expect 90 percent
of average flow. For the remainder of the South Platte
basin, flows are expected near 95 percent.

Stored water in the South Platte Basin was 111 percent of average
on February 1.



   North Platte Streamflow Fcst          South Platte Streamflow Fcst


PRECIPITATION MAPS
January 2020  WY 2020
January 2020 Precipitation Percent of 1981-2010 Average WY2020 Precipitation as Percent of 1981-2010 Average
January 2020 Basin Mean Precipitation          WY2020 Basin Mean Precipitation
January 2020 MBRFC Basin Mean Precipitation      WY2020 MBRFC Basin Mean Precipitation