April 1, 2025 Spring and Summer Streamflow Forecasts
Upper Missouri Basin
The high elevation snow pack in the Upper Missouri Basin as of April 1
was below average. The snow pack in the St. Mary Basin was 69 percent,
and the Milk River Basin was 72 percent.
March precipitation across the Upper Missouri Basin was near to below average.
Basin precipitation summaries for the Missouri Basin include: Milk St. Mary,
83 percent; Milk Canada, 67 percent; Lower Milk, 41 percent; above Toston,
109 percent; Toston to Ft. Peck, 73 percent.
March 2025 Upper Missouri Mean Precip Oct-Mar WY2025 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 62 percent of average
April-September flows. Runoff is expected to range around
87 percent of average for the Missouri Basin above Fort Peck,
Montana.
Upper Missouri April 1, 2025 Spring and Summer Streamflow Forecasts
Of the four major irrigation reservoirs in Montana; Lima
Reservoir had 93 percent average storage, Clark Canyon was
holding 110 percent of average water, Gibson Reservoir had 28
percent of average stored water, and Fresno Reservoir had
63 percent of average stored water.
Yellowstone Basin
The high elevation snow pack in the Yellowstone Basin was above to near average
on April 1. The snow pack in the Upper Yellowstone Basin was 99 percent
of average. The snow packs in the Wind, Bighorn, and Shoshone Basins were 111,
103, and 96 percent of average, respectively. The snow packs in the Tongue
and Powder basins were 100 and 90 percent of average, respectively.
Precipitation during March ranged from above to above average. The
upper Yellowstone River Basin received 104 percent of average precipitation
while the Lower Yellowstone River Basin reported 83 percent of average. The
Bighorn Basin received 144 percent of average precipitation while the
Wind River Basin received 204 percent of average. The Little Bighorn -
Upper Tongue Basin received 123 percent of average and the Powder River
had 114 percent of average precipitation.
March 2025 Yellowstone Mean Precip Oct-Mar WY2025 Yellowstone Mean Precip
Forecast streamflow in the Yellowstone Basin is below average
for the upcoming Spring and Summer. Stream flow for the
Yellowstone River above Sidney, Montana is forecast to be about
70 percent of average. Flow in the Tongue Basin is expected to be
83 percent of average. Flows in the Powder River are expected
to be about 50 percent of average.
Monthend storage at Boysen Reservoir was 89 percent of average.
Stored water in Buffalo Bill Reservoir was 89 percent of average.
Monthend storage was 98 percent of average at Bighorn Reservoir.
Yellowstone April 1, 2025 Spring and Summer Streamflow Forecasts
Platte Basin
The high elevation snow pack in the Upper North Platte Basin was
103 percent of average on April 1. The snow pack in the North Platte
Basin below Seminoe Reservoir was 98 percent of average. The snow
pack in the South Platte Basin was 97 percent of average.
Precipitation during March in the Upper North Platte Basin was 117
percent of average. In the Lower North Platte Basin, precipitation
was 145 percent of average. The North Platte Plains below Guernsy
Reservoir had 64 percent. The South Platte Mountains had 88
percent whereas the Plains had 122 percent of average March
precipitation.
March 2025 Platte Mean Precip Oct-Mar WY2025 Platte Mean Precip
Stream flow in the Platte Basin is forecast to range from
below to above average during the upcoming Spring and Summer.
Runoff for streams above Seminoe Reservoir are expected to be
about 70 percent of average. Streams in the South Platte
Basin above South Platte, Colorado can expect 88 percent
of average flow. For the remainder of the South Platte
basin, flows are expected near 87 percent.
Stored water in the South Platte Basin was 102 percent of average
on April 1.
North Platte Streamflow Fcst South Platte Streamflow Fcst
WATER SUPPLY FORECAST
NWS MISSOURI BASIN RIVER FORECAST CENTER
PLEASANT HILL MISSOURI
1403 CDT SUNDAY APRIL 06, 2025
DATA CURRENT AS OF: APRIL 01, 2025
MISSOURI/YELLOWSTONE/PLATTE RIVER BASIN FORECASTS
50% % 10% 90% AVG
FORECAST POINT PERIOD (KAF) AVG (KAF) (KAF) (KAF)
--------------------------------------------------------------------
Boysen Resvr Inflow Apr-Sep 387 54 735 194 720
SBDW4
Boysen Resvr Inflow Apr-Sep 916 103 1424 589 890
SBDW4N
Bighorn R at Kane Apr-Sep 810 82 1262 545 985
LVEW4
Bighorn R at Kane Apr-Sep 1461 101 2190 941 1440
LVEW4N
Greybull R at Meeteetse Apr-Sep 162 83 290 98 196
MEEW4
Greybull R at Meeteetse Apr-Sep 162 79 290 98 205
MEEW4N
Buffalo Bill Resvr Inflow Apr-Sep 564 69 752 427 815
CDYW4
Buffalo Bill Resvr Inflow Apr-Sep 649 71 830 510 910
CDYW4N
Keyhole Resvr Inflow Apr-Sep 10 250 37 3 4
KEYW4
St. Mary R nr Babb Apr-Sep 356 77 409 307 460
SMYM8
St. Mary R nr Babb Apr-Sep 338 63 394 290 535
SMYM8N
St. Mary R at Intl Boundary Apr-Sep 412 106 500 354 390
SMBM8
St. Mary R at Intl Boundary Apr-Sep 397 60 485 337 660
SMBM8N
Milk R nr Western Crossing Apr-Sep 9 8 32 5 113
PDBM8
Milk R nr Western Crossing Apr-Sep 13 32 45 6 41
PDBM8N
Milk R nr Eastern Crossing Apr-Sep 13 6 93 7 215
ERNM8
Milk R nr Eastern Crossing Apr-Sep 36 32 149 18 112
ERNM8N
North Platte R nr Northgate Apr-Sep 210 86 318 138 245
NGTC2
North Platte R nr Northgate Apr-Sep 265 90 373 188 295
NGTC2N
Encampment R nr Encampment Apr-Sep 103 66 140 76 156
ECRW4
Encampment R nr Encampment Apr-Sep 114 69 151 87 166
ECRW4N
Rock Cr nr Arlington Apr-Sep 47 89 56 37 53
KCRW4
Rock Cr nr Arlington Apr-Sep 47 89 57 37 53
KCRW4N
Seminoe Resvr Inflow Apr-Sep 605 79 830 422 765
SETW4
Seminoe Resvr Inflow Apr-Sep 780 85 986 585 920
SETW4N
Laramie R nr Woods Landing Apr-Sep 53 49 80 27 108
WODW4
Laramie R nr Woods Landing Apr-Sep 88 62 115 55 142
WODW4N
Little Laramie R nr Filmore Apr-Sep 58 105 71 44 55
SMTW4
Little Laramie R nr Filmore Apr-Sep 60 105 73 47 57
SMTW4N
Antero Resvr Inflow Apr-Sep 11 79 18 7 14
ANRC2
Antero Resvr Inflow Apr-Sep 11 79 18 7 14
ANRC2N
Spinney Mountain Resvr Inflow Apr-Sep 36 63 60 29 57
SPYC2
Spinney Mountain Resvr Inflow Apr-Sep 32 71 57 20 45
SPYC2N
Elevenmile Canyon Resvr Inflow Apr-Sep 36 61 47 31 59
EVNC2
Elevenmile Canyon Resvr Inflow Apr-Sep 35 70 61 21 50
EVNC2N
Cheesman Lk Inflow Apr-Sep 54 54 96 43 100
CHEC2
Cheesman Lk Inflow Apr-Sep 66 71 114 40 93
CHEC2N
S Platte R at S Platte Apr-Sep 319 133 476 299 240
SPTC2
S Platte R at S Platte Apr-Sep 135 66 250 92 205
SPTC2N
Bear Cr at Morrison Apr-Sep 32 123 58 18 26
MRRC2
Bear Cr at Morrison Apr-Sep 32 123 58 18 26
MRRC2N
Clear Cr at Golden Apr-Sep 101 86 154 77 118
GLDC2
Clear Cr at Golden Apr-Sep 114 87 170 88 131
GLDC2N
St. Vrain Cr at Lyons Apr-Sep 47 59 88 35 79
LNSC2
St. Vrain Cr at Lyons Apr-Sep 68 62 120 54 109
LNSC2N
Boulder Cr nr Orodell Apr-Sep 31 66 59 22 47
OROC2
Boulder Cr nr Orodell Apr-Sep 46 88 75 35 52
OROC2N
S Boulder Cr nr Eldorado Sprgs Apr-Sep 23 66 42 13 35
BELC2
S Boulder Cr nr Eldorado Sprgs Apr-Sep 23 58 54 13 40
BELC2N
Cache La Poudre at Canyon Mouth Apr-Sep 163 151 281 103 108
FTDC2
Cache La Poudre at Canyon Mouth Apr-Sep 210 100 329 137 210
FTDC2N
Lima Resvr Inflow Apr-Sep 32 42 52 26 76
LRRM8
Lima Resvr Inflow Apr-Sep 32 41 52 26 79
LRRM8N
Clark Canyon Resvr Inflow Apr-Sep 50 45 62 45 110
CLKM8
Clark Canyon Resvr Inflow Apr-Sep 89 45 125 76 198
CLKM8N
Beaverhead R at Barretts Apr-Sep 121 61 134 117 199
BARM8
Beaverhead R at Barretts Apr-Sep 119 42 159 106 280
BARM8N
Ruby R Resvr Inflow Apr-Sep 64 73 82 56 88
ALRM8
Ruby R Resvr Inflow Apr-Sep 64 66 82 56 97
ALRM8N
Big Hole R nr Melrose Apr-Sep 503 85 701 424 595
MLRM8
Big Hole R nr Melrose Apr-Sep 567 86 766 487 660
MLRM8N
Hebgen Resvr Inflow Apr-Sep 438 94 499 377 465
HBDM8
Hebgen Resvr Inflow Apr-Sep 438 94 499 377 465
HBDM8N
Ennis Resvr Inflow Apr-Sep 702 98 822 649 715
ELMM8
Ennis Resvr Inflow Apr-Sep 754 103 888 666 730
ELMM8N
Gallatin R nr Gateway Apr-Sep 358 75 447 297 475
GLGM8
Gallatin R nr Gateway Apr-Sep 358 75 447 297 475
GLGM8N
Gallatin R at Logan Apr-Sep 353 70 498 279 505
LOGM8
Gallatin R at Logan Apr-Sep 504 78 624 423 650
LOGM8N
Missouri R at Toston Apr-Sep 1514 73 2191 1307 2060
TOSM8
Missouri R at Toston Apr-Sep 2223 79 2895 1996 2830
TOSM8N
Missouri R at Fort Benton Apr-Sep 1878 61 2514 1737 3060
FBNM8
Missouri R at Fort Benton Apr-Sep 3443 84 4507 3024 4100
FBNM8N
Missouri R nr Virgelle Apr-Sep 2023 59 2676 1860 3420
VRGM8
Missouri R nr Virgelle Apr-Sep 3889 85 5027 3429 4560
VRGM8N
Missouri R nr Landusky Apr-Sep 2411 66 3190 2219 3680
LDKM8
Missouri R nr Landusky Apr-Sep 4335 89 5636 3887 4890
LDKM8N
Missouri R below Fort Peck Dam Apr-Sep 2741 71 3526 2493 3840
FPKM8
Missouri R below Fort Peck Dam Apr-Sep 4772 92 6102 4234 5180
FPKM8N
Gibson Resvr Inflow Apr-Sep 346 77 497 276 450
AGSM8
Gibson Resvr Inflow Apr-Sep 346 77 497 276 450
AGSM8N
Marias R nr Shelby Apr-Sep 257 59 411 193 435
SHLM8
Marias R nr Shelby Apr-Sep 305 62 459 238 490
SHLM8N
Musselshell R at Harlowton Apr-Sep 43 54 76 25 80
HLWM8
Musselshell R at Harlowton Apr-Sep 55 58 93 36 95
HLWM8N
Yellowstone R at Yellowstone Lk Apr-Sep 396 49 483 322 815
YLOW4
Yellowstone R at Yellowstone Lk Apr-Sep 548 65 652 430 840
YLOW4N
Yellowstone R at Corwin Sprgs Apr-Sep 1144 58 1436 985 1980
CORM8
Yellowstone R at Corwin Sprgs Apr-Sep 1366 66 1693 1153 2070
CORM8N
Yellowstone R at Livingston Apr-Sep 1290 56 1619 1108 2290
LIVM8
Yellowstone R at Livingston Apr-Sep 1628 67 2014 1376 2440
LIVM8N
Yellowstone R at Billings Apr-Sep 2086 51 2897 1678 4070
BILM8
Yellowstone R at Billings Apr-Sep 3079 64 3878 2620 4790
BILM8N
Yellowstone R at Miles City Apr-Sep 3375 58 4668 2799 5850
MILM8
Yellowstone R at Miles City Apr-Sep 5725 74 7238 4629 7690
MILM8N
Yellowstone R at Sidney Apr-Sep 3194 56 4616 2557 5710
SIDM8
Yellowstone R at Sidney Apr-Sep 5932 74 7590 4731 8060
SIDM8N
Boulder R at Big Timber Apr-Sep 174 52 259 133 335
BTMM8
Boulder R at Big Timber Apr-Sep 216 58 298 176 375
BTMM8N
Stillwater R nr Absarokee Apr-Sep 282 52 391 225 540
SRAM8
Stillwater R nr Absarokee Apr-Sep 339 57 447 285 595
SRAM8N
Clks Fk Yellowstone R nr Belfry Apr-Sep 434 70 560 359 620
BFYM8
Clks Fk Yellowstone R nr Belfry Apr-Sep 505 73 630 432 695
BFYM8N
Bighorn R nr St. Xavier Apr-Sep 961 67 1481 786 1430
STXM8
Bighorn R nr St. Xavier Apr-Sep 2215 90 3206 1555 2460
STXM8N
Little Bighorn R nr Hardin Apr-Sep 137 108 189 90 127
HRDM8
Little Bighorn R nr Hardin Apr-Sep 137 108 189 90 127
HRDM8N
Tongue R nr Dayton Apr-Sep 73 76 101 53 96
DAYW4
Tongue R nr Dayton Apr-Sep 79 78 107 58 101
DAYW4N
Tongue R nr Decker Apr-Sep 164 70 240 108 235
DSLM8
Tongue R nr Decker Apr-Sep 212 88 287 153 240
DSLM8N
Tongue R Resvr Inflow Apr-Sep 165 70 251 109 235
DKRM8
Tongue R Resvr Inflow Apr-Sep 213 87 298 153 245
DKRM8N
Powder R at Moorhead Apr-Sep 97 43 259 51 225
MHDM8
Powder R at Moorhead Apr-Sep 132 49 298 75 270
MHDM8N
Powder R nr Locate Apr-Sep 110 42 277 55 260
LOCM8
Powder R nr Locate Apr-Sep 152 50 343 84 305
LOCM8N
Locations with an `N` suffix indicate natural flows excluding
stream augmentations.
KAF: Thousands of Acre-feet
%AVG: Current 50%/AVG
AVG: Average(50%) seasonal runoff voulme as simulated by the river
forecast model considering acontinuous simulation of the basin
response to historic climate data (observed precipitation and
temperatures) over the period of 1991-2020.
The 50%, 10% and 90% columns indicate the probability that the
actual volume will exceed the forecast for the valid time period.
Beginning April 1, May and June official forecasts include observed
runoff volume up to official forecast date.
For more information, please visit: www.weather.gov/mbrfc/water
