May 1, 2024 Spring and Summer Streamflow Forecasts
Upper Missouri Basin
The high elevation snow pack in the Upper Missouri Basin as of May 1
was below average. The snow pack in the St. Mary Basin was 77 percent,
and the Milk River Basin was 65 percent.
April precipitation across the Upper Missouri Basin was below average.
Basin precipitation summaries for the Missouri Basin include: Milk St. Mary,
64 percent; Milk Canada, 79 percent; Lower Milk, 55 percent; above Toston,
73 percent; Toston to Ft. Peck, 73 percent.
April 2024 Upper Missouri Mean Precip Oct-Apr WY2024 Upper Missouri Mean Precip
Stream flow in the Upper Missouri Basin is forecast to be
below to near average during the upcoming Spring and Summer.
The St. Mary River is forecast to have 57 percent of average
May-September flows. Runoff is expected to range around
47 percent of average for the Missouri Basin above Fort Peck,
Montana.
Upper Missouri May 1, 2024 Spring and Summer Streamflow Forecasts
Of the four major irrigation reservoirs in Montana; Lima
Reservoir had 123 percent average storage, Clark Canyon was
holding 112 percent of average water, Gibson Reservoir had 70
percent of average stored water, and Fresno Reservoir had
52 percent of average stored water.
Yellowstone Basin
The high elevation snow pack in the Yellowstone Basin was below average
on May 1. The snow pack in the Upper Yellowstone Basin was 74 percent
of average. The snow packs in the Wind, Bighorn, and Shoshone Basins were 96,
87, and 81 percent of average, respectively. The snow packs in the Tongue
and Powder basins were 79 and 70 percent of average, respectively.
Precipitation during April was below to near average. The upper Yellowstone River
Basin received 81 percent of average precipitation while the Lower
Yellowstone River Basin reported 59 percent of average. The Bighorn
Basin received 110 percent of average precipitation while the
Wind River Basin received 80 percent of average. The Little Bighorn -
Upper Tongue Basin received 74 percent of average and the Powder River
had 77 percent of average precipitation.
April 2024 Yellowstone Mean Precip Oct-Apr WY2024 Yellowstone Mean Precip
Forecast stream flow in the Yellowstone Basin is below to near average
for the upcoming Spring and Summer. Stream flow for the
Yellowstone River above Sidney, Montana is forecast to be about
80 percent of average. Flow in the Tongue Basin is expected to be
75 percent of average. Flows in the Powder River are expected
to be about 75 percent of average.
Monthend storage at Boysen Reservoir was 103 percent of average.
Stored water in Buffalo Bill Reservoir was 118 percent of average.
Monthend storage was 101 percent of average at Bighorn Reservoir.
Yellowstone May 1, 2024 Spring and Summer Streamflow Forecasts
Platte Basin
The high elevation snow pack in the Upper North Platte Basin was
97 percent of average on May 1. The snow pack in the North Platte
Basin below Seminoe Reservoir was 62 percent of average. The snow
pack in the South Platte Basin was 106 percent of average.
Precipitation during April in the Upper North Platte Basin was 103
percent of average. In the Lower North Platte Basin, precipitation
was 98 percent of average. The North Platte Plains below Guernsy
Reservoir had 99 percent. The South Platte Mountains had 97
percent whereas the Plains had 114 percent of average April
precipitation.
April 2024 Platte Mean Precip Oct-Apr WY2024 Platte Mean Precip
Stream flow in the Platte Basin is forecast to be near
to above average during the upcoming Spring and Summer. Runoff
for streams above Seminoe Reservoir are expected to be
about 110 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 80 percent.
Stored water in the South Platte Basin was 106 percent of average
on May 1.
North Platte Streamflow Fcst South Platte Streamflow Fcst
WATER SUPPLY FORECAST
NWS MISSOURI BASIN RIVER FORECAST CENTER
PLEASANT HILL MISSOURI
1122 CDT FRIDAY MAY 03, 2024
DATA CURRENT AS OF: MAY 01, 2024
MISSOURI/YELLOWSTONE/PLATTE RIVER BASIN FORECASTS
50% % 10% 90% AVG
FORECAST POINT PERIOD (KAF) AVG (KAF) (KAF) (KAF)
--------------------------------------------------------------------
Boysen Resvr Inflow May-Sep 621 86 976 413 720
SBDW4
Boysen Resvr Inflow May-Sep 1110 125 1502 884 890
SBDW4N
Bighorn R at Kane May-Sep 1014 103 1474 805 985
LVEW4
Bighorn R at Kane May-Sep 1916 133 2557 1573 1440
LVEW4N
Greybull R at Meeteetse May-Sep 263 134 371 227 196
MEEW4
Greybull R at Meeteetse May-Sep 263 128 372 227 205
MEEW4N
Buffalo Bill Resvr Inflow May-Sep 645 79 812 556 815
CDYW4
Buffalo Bill Resvr Inflow May-Sep 733 81 895 650 910
CDYW4N
Keyhole Resvr Inflow May-Sep 4 100 11 3 4
KEYW4
St. Mary R nr Babb May-Sep 327 71 390 288 460
SMYM8
St. Mary R nr Babb May-Sep 311 58 375 271 535
SMYM8N
St. Mary R at Intl Boundary May-Sep 257 66 346 201 390
SMBM8
St. Mary R at Intl Boundary May-Sep 356 54 443 307 660
SMBM8N
Milk R nr Western Crossing May-Sep 14 12 37 11 113
PDBM8
Milk R nr Western Crossing May-Sep 19 46 49 13 41
PDBM8N
Milk R nr Eastern Crossing May-Sep 152 71 231 141 215
ERNM8
Milk R nr Eastern Crossing May-Sep 50 45 167 29 112
ERNM8N
North Platte R nr Northgate May-Sep 301 123 401 228 245
NGTC2
North Platte R nr Northgate May-Sep 350 119 449 276 295
NGTC2N
Encampment R nr Encampment May-Sep 154 99 176 130 156
ECRW4
Encampment R nr Encampment May-Sep 162 98 184 138 166
ECRW4N
Rock Cr nr Arlington May-Sep 52 98 59 45 53
KCRW4
Rock Cr nr Arlington May-Sep 52 98 59 46 53
KCRW4N
Seminoe Resvr Inflow May-Sep 892 117 1056 685 765
SETW4
Seminoe Resvr Inflow May-Sep 1045 114 1204 853 920
SETW4N
Laramie R nr Woods Landing May-Sep 64 59 98 41 108
WODW4
Laramie R nr Woods Landing May-Sep 100 70 134 77 142
WODW4N
Little Laramie R nr Filmore May-Sep 66 120 79 54 55
SMTW4
Little Laramie R nr Filmore May-Sep 68 119 81 56 57
SMTW4N
Antero Resvr Inflow May-Sep 14 100 18 11 14
ANRC2
Antero Resvr Inflow May-Sep 14 100 18 11 14
ANRC2N
Spinney Mountain Resvr Inflow May-Sep 51 89 71 41 57
SPYC2
Spinney Mountain Resvr Inflow May-Sep 40 89 61 31 45
SPYC2N
Elevenmile Canyon Resvr Inflow May-Sep 49 83 69 42 59
EVNC2
Elevenmile Canyon Resvr Inflow May-Sep 46 92 66 34 50
EVNC2N
Cheesman Lk Inflow May-Sep 79 79 114 63 100
CHEC2
Cheesman Lk Inflow May-Sep 80 86 117 61 93
CHEC2N
S Platte R at S Platte May-Sep 321 134 377 297 240
SPTC2
S Platte R at S Platte May-Sep 140 68 200 108 205
SPTC2N
Bear Cr at Morrison May-Sep 21 81 30 15 26
MRRC2
Bear Cr at Morrison May-Sep 21 81 30 15 26
MRRC2N
Clear Cr at Golden May-Sep 86 73 107 71 118
GLDC2
Clear Cr at Golden May-Sep 98 75 120 82 131
GLDC2N
St. Vrain Cr at Lyons May-Sep 65 82 93 55 79
LNSC2
St. Vrain Cr at Lyons May-Sep 87 80 119 75 109
LNSC2N
Boulder Cr nr Orodell May-Sep 40 85 58 35 47
OROC2
Boulder Cr nr Orodell May-Sep 56 108 74 50 52
OROC2N
S Boulder Cr nr Eldorado Sprgs May-Sep 34 97 43 31 35
BELC2
S Boulder Cr nr Eldorado Sprgs May-Sep 37 92 56 31 40
BELC2N
Cache La Poudre at Canyon Mouth May-Sep 173 160 241 136 108
FTDC2
Cache La Poudre at Canyon Mouth May-Sep 190 90 264 151 210
FTDC2N
Lima Resvr Inflow May-Sep 38 50 53 29 76
LRRM8
Lima Resvr Inflow May-Sep 38 48 53 29 79
LRRM8N
Clark Canyon Resvr Inflow May-Sep 130 118 188 114 110
CLKM8
Clark Canyon Resvr Inflow May-Sep 179 90 243 162 198
CLKM8N
Beaverhead R at Barretts May-Sep 190 95 203 174 199
BARM8
Beaverhead R at Barretts May-Sep 212 76 278 191 280
BARM8N
Ruby R Resvr Inflow May-Sep 78 89 92 66 88
ALRM8
Ruby R Resvr Inflow May-Sep 79 81 94 67 97
ALRM8N
Big Hole R nr Melrose May-Sep 423 71 606 351 595
MLRM8
Big Hole R nr Melrose May-Sep 488 74 670 417 660
MLRM8N
Hebgen Resvr Inflow May-Sep 477 103 539 437 465
HBDM8
Hebgen Resvr Inflow May-Sep 477 103 539 437 465
HBDM8N
Ennis Resvr Inflow May-Sep 646 90 749 595 715
ELMM8
Ennis Resvr Inflow May-Sep 684 94 789 628 730
ELMM8N
Gallatin R nr Gateway May-Sep 337 71 420 286 475
GLGM8
Gallatin R nr Gateway May-Sep 337 71 420 286 475
GLGM8N
Gallatin R at Logan May-Sep 364 72 488 302 505
LOGM8
Gallatin R at Logan May-Sep 511 79 626 457 650
LOGM8N
Missouri R at Toston May-Sep 1560 76 1946 1370 2060
TOSM8
Missouri R at Toston May-Sep 2249 79 2710 2074 2830
TOSM8N
Missouri R at Fort Benton May-Sep 1784 58 1995 1695 3060
FBNM8
Missouri R at Fort Benton May-Sep 3003 73 3667 2743 4100
FBNM8N
Missouri R nr Virgelle May-Sep 1926 56 2140 1805 3420
VRGM8
Missouri R nr Virgelle May-Sep 3382 74 4152 3084 4560
VRGM8N
Missouri R nr Landusky May-Sep 1949 53 2202 1784 3680
LDKM8
Missouri R nr Landusky May-Sep 3554 73 4337 3248 4890
LDKM8N
Missouri R below Fort Peck Dam May-Sep 2185 57 2500 1907 3840
FPKM8
Missouri R below Fort Peck Dam May-Sep 3806 73 4603 3453 5180
FPKM8N
Gibson Resvr Inflow May-Sep 299 66 415 250 450
AGSM8
Gibson Resvr Inflow May-Sep 299 66 415 249 450
AGSM8N
Marias R nr Shelby May-Sep 258 59 386 199 435
SHLM8
Marias R nr Shelby May-Sep 310 63 440 248 490
SHLM8N
Musselshell R at Harlowton May-Sep 67 84 115 44 80
HLWM8
Musselshell R at Harlowton May-Sep 83 87 131 59 95
HLWM8N
Yellowstone R at Yellowstone Lk May-Sep 769 94 821 669 815
YLOW4
Yellowstone R at Yellowstone Lk May-Sep 883 105 967 777 840
YLOW4N
Yellowstone R at Corwin Sprgs May-Sep 1527 77 1723 1318 1980
CORM8
Yellowstone R at Corwin Sprgs May-Sep 1731 84 1951 1518 2070
CORM8N
Yellowstone R at Livingston May-Sep 1673 73 1922 1457 2290
LIVM8
Yellowstone R at Livingston May-Sep 1933 79 2188 1711 2440
LIVM8N
Yellowstone R at Billings May-Sep 2676 66 3340 2366 4070
BILM8
Yellowstone R at Billings May-Sep 3583 75 4230 3230 4790
BILM8N
Yellowstone R at Miles City May-Sep 4300 74 5520 3714 5850
MILM8
Yellowstone R at Miles City May-Sep 6826 89 8151 6069 7690
MILM8N
Yellowstone R at Sidney May-Sep 4265 75 5538 3591 5710
SIDM8
Yellowstone R at Sidney May-Sep 7175 89 8582 6332 8060
SIDM8N
Boulder R at Big Timber May-Sep 158 47 197 130 335
BTMM8
Boulder R at Big Timber May-Sep 201 54 238 173 375
BTMM8N
Stillwater R nr Absarokee May-Sep 354 66 438 303 540
SRAM8
Stillwater R nr Absarokee May-Sep 414 70 495 363 595
SRAM8N
Clks Fk Yellowstone R nr Belfry May-Sep 444 72 548 385 620
BFYM8
Clks Fk Yellowstone R nr Belfry May-Sep 516 74 620 457 695
BFYM8N
Bighorn R nr St. Xavier May-Sep 1242 87 1848 1049 1430
STXM8
Bighorn R nr St. Xavier May-Sep 2860 116 3675 2423 2460
STXM8N
Little Bighorn R nr Hardin May-Sep 91 72 151 75 127
HRDM8
Little Bighorn R nr Hardin May-Sep 91 72 151 75 127
HRDM8N
Tongue R nr Dayton May-Sep 66 69 95 47 96
DAYW4
Tongue R nr Dayton May-Sep 71 70 101 53 101
DAYW4N
Tongue R nr Decker May-Sep 144 61 233 108 235
DSLM8
Tongue R nr Decker May-Sep 189 79 277 153 240
DSLM8N
Tongue R Resvr Inflow May-Sep 129 55 222 94 235
DKRM8
Tongue R Resvr Inflow May-Sep 177 72 269 141 245
DKRM8N
Powder R at Moorhead May-Sep 142 63 326 112 225
MHDM8
Powder R at Moorhead May-Sep 188 70 368 157 270
MHDM8N
Powder R nr Locate May-Sep 187 72 365 143 260
LOCM8
Powder R nr Locate May-Sep 236 77 406 188 305
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
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