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Snowmelt Peak Streamflow Dates Forecast Table

Snowmelt Peak Streamflow Dates Forecast Table

The snowmelt peak dates below are predictions for the 2015 water year and are computed using May 7th, 2015, data. The dates below are predictions for snowmelt driven runoff and does not account for rain driven streamflow runoff occurring in the past, present or future. Peak streamflow forecasts ranges and date averages below are for daily average flow (cubic feet per second) and do not represent instantaneous peaks.  

Peak date forecasts for streamflow points affected by upstream reservoirs were not calculated with known reservoir operations other than what has typically occurred in the past. 

Columbia River Basin
Watershed Snowmelt Peak Flow Date Range 1981-2010 Average
Bitterroot River near Darby Peaked on 5/6 5/22
Bitterroot River at Missoula Peaked on 5/6 5/24
Blackfoot River near Bonner Peaked on 5/6  to 5/7 5/21
Clark Fork River above Missoula Peaked on 5/7 5/25
Clark Fork River at St. Regis peak on 5/7 5/25
Clark Fork River below Missoula Peaked on 5/6  to 5/7 5/25
Clark Fork River near Drummond Peaked on 5/6 5/25
Como Reservoir Inflow Peaked 5/22
Fisher River near Libby Peaked on 4/23 5/15
Little Blackfoot River near Garrison Peaked on 5/6 5/14
Lower Willow Creek Reservoir Inflow Peaked 5/13
Middle Fork Flathead River near West Glacier Peaked on 5/6 5/20
Middle Fork Rock Creek near Phillipsburg Peaked on 5/6 5/24
Mill Creek near Niarada Peaked on 3/31 5/5
Nevada Creek near Helmville Peaked on 5/6 5/19
North Fork Flathead River near Columbia Falls Peaked on 5/6 5/22
Prospect Creek at Thompson Falls Peaked on 5/4 5/15
South Fork Flathead River above Twin Creeks Peaked on 5/6 5/21
South Fork Jocko River near Arlee Peaked on 5/6 5/17
Swan River near Big Fork 5/28 to 6/1 5/24
Thompson River near Thompson Falls Peaked on 5/4 5/16
Tobacco River near Eureka Peaked on 5/6 5/20
Yaak River near Troy Peaked on 5/2 5/15

 

Missouri River Basin
Watershed Projected Snowmelt Peak Flow Date Range 1981-2010 Average Snowmelt Peak Date
Badger Creek near Browning Peaked on 5/6 5/22
Big Hole River below Big Lake Creek at Wisdom Peaked on 5/7 6/1
Big Hole River near Melrose Peaked on 5/6 5/29
Boulder River near Boulder Peaked on 5/6 5/22
Clark Canyon Reservoir Inflow Peaked 6/5
Cut Bank Creek near Browning Peaked on 5/8 5/20
Dearborn River near Craig Peaked on 5/5 5/18
Gallatin River near Gateway 6/2 to 6/7 6/2
Gallatin River at Logan 6/3 to 6/8 6/1
Gibson Reservoir Inflow Peaked on 5/6 5/24
Hebgen Reservoir Inflow Peaked on 5/4 5/22
Hyalite Reservoir Inflow 5/23 to 5/28 6/2
Jefferson River near Three Forks Peaked on 5/8 5/30
Lima Reservoir Inflow Peaked on 3/21 to 3/22 5/16
Madison River near West Yellowstone Peaked on 5/7 5/21
Marias River near Shelby Peaked on 5/7 5/23
Missouri River at Toston Peaked on 5/18 6/2
Musselshell River at Harlowton Peaked on 5/7 5/24
Musselshell River near Martinsdale Peaked on 5/6 5/21
North Fork Musselshell River near Delpine Peaked 5/25
Ruby Reservoir Inflow Peaked on 5/2 5/27
Sheep Creek near White Sulphur Springs Peaked 5/24
Smith River below Eagle Creek near Fort Logan Peaked on 5/6 5/21
Swift Reservoir Inflow Peaked on 3/16 5/23
Two Medicine River near Browning Peaked on 5/6 5/22
Willow Creek near Harrison Peaked on 5/2 to 5/3 6/1

 

Saskatchewan River Basin
Watershed Projected Snowmelt Peak Flow Date Range 1981-2010 Average Snowmelt Peak Date
Lake Sherburne Inflow Peaked on 5/8 5/22
St. Mary River at International Boundary Peaked on 5/9 ***

 

Yellowstone River Basin
Watershed Projected Snowmelt Peak Flow Date Range 1981-2010 Average Snowmelt Peak Date
Boulder River near Big Timber Peaked on 5/6 6/4
Big Goose Creek near Sheridan Wyoming 5/25 to 5/30 5/26
Clarks Fork River near Belfry 6/3 to 6/8 6/4
Cooney Reservoir inflow Peaked on 4/27 5/31
Little Bighorn River near Hardin Peaked on 5/9 5/28
Little Goose Creek near Bighorn Wyoming 5/23 to 5/28 5/25
West Rosebud near Roscoe 5/23 to 5/28 6/9
Powder River at Moorehead Peaked on 5/9 5/22
Shields River near Livingston Peaked on 5/1 and 5/6 5/27
Stillwater River near Absarokee 6/3 to 6/8 6/5
Tongue River at Dayton Wyoming Peaked on 5/6 5/26
Tongue River Reservoir Inflow Peaked on 5/9 5/24
Yellowstone River at Billings 5/31 to 6/4 6/7
Yellowstone River at Corwin Springs 5/30 to 6/3 6/2
Yellowstone River at Lake Outlet 6/8 to 6/13 6/25
Yellowstone River at Livingston 5/30 to 6/3 6/4