May 1, 2022 Spring and Summer Streamflow Forecasts
Upper Missouri Basin
The high elevation snow pack in the Upper Missouri Basin as of May 1
was near to above average. The snow pack in the St. Mary Basin was 130 percent,
and the Milk River Basin was 85 percent.
April precipitation across the Upper Missouri Basin ranged from below to above
average. Basin precipitation summaries for the Missouri Basin include: Milk St. Mary,
56 percent; Milk Canada, 45 percent; Lower Milk, 98 percent; above Toston,
109 percent; Toston to Ft. Peck, 120 percent.
April 2022 Upper Missouri Mean Precip Oct-Apr WY2022 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 60 percent of average
May-September flows. Runoff is expected to range around
73 percent of average for the Missouri Basin above Fort Peck,
Montana.
Upper Missouri May 1, 2022 Spring and Summer Streamflow Forecasts
Of the four major irrigation reservoirs in Montana; Lima
Reservoir had 62 percent average storage, Clark Canyon was
holding 71 percent of average water, Gibson Reservoir had 56
percent of average stored water, and Fresno Reservoir had
68 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 73 percent
of average. The snow packs in the Wind, Bighorn, and Shoshone Basins were 84,
81, and 74 percent of average, respectively. The snow packs in the Tongue
and Powder basins were 88 and 80 percent of average, respectively.
Precipitation during April was above average. The upper Yellowstone River
Basin received 134 percent of average precipitation while the Lower
Yellowstone River Basin reported 195 percent of average. The Bighorn
Basin received 164 percent of average precipitation while the
Wind River Basin received 126 percent of average. The Little Bighorn -
Upper Tongue Basin received 202 percent of average and the Powder River
had 169 percent of average precipitation.
April 2022 Yellowstone Mean Precip Oct-Apr WY2022 Yellowstone Mean Precip
Forecast stream flow 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
71 percent of average. Flow in the Tongue Basin is expected to be
63 percent of average. Flows in the Powder River are expected
to be about 55 percent of average.
Monthend storage at Boysen Reservoir was 113 percent of average.
Stored water in Buffalo Bill Reservoir was 95 percent of average.
Monthend storage was 100 percent of average at Bighorn Reservoir.
Yellowstone May 1, 2022 Spring and Summer Streamflow Forecasts
Platte Basin
The high elevation snow pack in the Upper North Platte Basin was
91 percent of average on May 1. The snow pack in the North Platte
Basin below Seminoe Reservoir was 85 percent of average. The snow
pack in the South Platte Basin was 90 percent of average.
Precipitation during April in the Upper North Platte Basin was 98
percent of average. In the Lower North Platte Basin, precipitation
was 84 percent of average. The North Platte Plains below Guernsy
Reservoir had 31 percent. The South Platte Mountains had 38
percent whereas the Plains had 11 percent of average April
precipitation.
April 2022 Platte Mean Precip Oct-Apr WY2022 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 85 percent of average. Streams in the South Platte
Basin above South Platte, Colorado can expect 45 percent
of average flow. For the remainder of the South Platte
basin, flows are expected near 40 percent.
Stored water in the South Platte Basin was 100 percent of average
on May 1.
North Platte Streamflow Fcst South Platte Streamflow Fcst
FGUS63 KKRF 021509
ESPKRF
WATER SUPPLY FORECAST
NWS MISSOURI BASIN RIVER FORECAST CENTER
PLEASANT HILL MISSOURI
0659 CDT MONDAY MAY 02, 2022
DATA CURRENT AS OF: MAY 01, 2022
MISSOURI/YELLOWSTONE/PLATTE RIVER BASIN FORECASTS
50% % 10% 90% AVG
FORECAST POINT PERIOD (KAF) AVG (KAF) (KAF) (KAF)
--------------------------------------------------------------------
Boysen Resvr Inflow May-Sep 407 61 724 223 666
SBDW4
Boysen Resvr Inflow May-Sep 836 101 1206 623 831
SBDW4N
Bighorn R at Kane May-Sep 869 98 1447 661 885
LVEW4
Bighorn R at Kane May-Sep 1443 109 2067 1082 1322
LVEW4N
Greybull R at Meeteetse May-Sep 150 79 248 119 190
MEEW4
Greybull R at Meeteetse May-Sep 150 76 248 119 197
MEEW4N
Buffalo Bill Resvr Inflow May-Sep 398 50 545 309 792
CDYW4
Buffalo Bill Resvr Inflow May-Sep 475 55 617 390 865
CDYW4N
St. Mary R nr Babb May-Sep 242 57 302 201 424
SMYM8
St. Mary R nr Babb May-Sep 251 62 312 209 403
SMYM8N
St. Mary R at Intl Boundary May-Sep 173 48 251 117 362
SMBM8
St. Mary R at Intl Boundary May-Sep 298 59 378 248 506
SMBM8N
Milk R nr Western Crossing May-Sep 6 5 24 3 109
PDBM8
Milk R nr Western Crossing May-Sep 10 40 32 5 24
PDBM8N
Milk R nr Eastern Crossing May-Sep 128 70 184 118 184
ERNM8
Milk R nr Eastern Crossing May-Sep 23 25 118 11 95
ERNM8N
North Platte R nr Northgate May-Sep 231 111 330 160 209
NGTC2
North Platte R nr Northgate May-Sep 284 111 381 213 257
NGTC2N
Encampment R nr Encampment May-Sep 120 85 140 96 142
ECRW4
Encampment R nr Encampment May-Sep 129 85 150 106 152
ECRW4N
Rock Cr nr Arlington May-Sep 42 83 49 35 51
KCRW4
Rock Cr nr Arlington May-Sep 42 82 49 35 52
KCRW4N
Seminoe Resvr Inflow May-Sep 726 108 895 526 669
SETW4
Seminoe Resvr Inflow May-Sep 878 107 1046 688 818
SETW4N
Laramie R nr Woods Landing May-Sep 54 53 86 31 101
WODW4
Laramie R nr Woods Landing May-Sep 88 67 121 65 133
WODW4N
Little Laramie R nr Filmore May-Sep 48 113 60 38 42
SMTW4
Little Laramie R nr Filmore May-Sep 50 92 62 40 54
SMTW4N
Antero Resvr Inflow May-Sep 7 57 11 5 13
ANRC2
Antero Resvr Inflow May-Sep 7 57 11 5 13
ANRC2N
Spinney Mountain Resvr Inflow May-Sep 28 54 41 23 53
SPYC2
Spinney Mountain Resvr Inflow May-Sep 21 51 34 14 41
SPYC2N
Elevenmile Canyon Resvr Inflow May-Sep 32 60 42 28 53
EVNC2
Elevenmile Canyon Resvr Inflow May-Sep 24 50 40 15 47
EVNC2N
Cheesman Lk Inflow May-Sep 47 51 69 35 92
CHEC2
Cheesman Lk Inflow May-Sep 44 53 74 27 84
CHEC2N
S Platte R at S Platte May-Sep 269 122 286 253 220
SPTC2
S Platte R at S Platte May-Sep 85 45 131 54 189
SPTC2N
Bear Cr at Morrison May-Sep 5 22 10 3 24
MRRC2
Bear Cr at Morrison May-Sep 5 22 10 3 24
MRRC2N
Clear Cr at Golden May-Sep 44 39 64 31 113
GLDC2
Clear Cr at Golden May-Sep 51 40 73 37 126
GLDC2N
St. Vrain Cr at Lyons May-Sep 40 55 58 30 74
LNSC2
St. Vrain Cr at Lyons May-Sep 62 61 88 49 102
LNSC2N
Boulder Cr nr Orodell May-Sep 24 52 37 20 45
OROC2
Boulder Cr nr Orodell May-Sep 38 80 54 34 48
OROC2N
S Boulder Cr nr Eldorado Sprgs May-Sep 15 47 21 11 32
BELC2
S Boulder Cr nr Eldorado Sprgs May-Sep 15 41 25 11 37
BELC2N
Cache La Poudre at Canyon Mouth May-Sep 167 162 215 134 103
FTDC2
Cache La Poudre at Canyon Mouth May-Sep 192 95 249 155 201
FTDC2N
Lima Resvr Inflow May-Sep 15 28 23 11 54
LRRM8
Lima Resvr Inflow May-Sep 15 27 23 11 57
LRRM8N
Clark Canyon Resvr Inflow May-Sep 27 28 33 25 96
CLKM8
Clark Canyon Resvr Inflow May-Sep 51 28 73 43 180
CLKM8N
Beaverhead R at Barretts May-Sep 99 58 107 95 169
BARM8
Beaverhead R at Barretts May-Sep 77 29 101 66 261
BARM8N
Ruby R Resvr Inflow May-Sep 53 67 64 43 79
ALRM8
Ruby R Resvr Inflow May-Sep 53 61 64 43 87
ALRM8N
Big Hole R nr Melrose May-Sep 487 95 688 414 510
MLRM8
Big Hole R nr Melrose May-Sep 549 96 749 473 574
MLRM8N
Hebgen Resvr Inflow May-Sep 314 78 365 281 402
HBDM8
Hebgen Resvr Inflow May-Sep 314 78 365 281 402
HBDM8N
Ennis Resvr Inflow May-Sep 458 73 516 419 626
ELMM8
Ennis Resvr Inflow May-Sep 503 78 587 446 641
ELMM8N
Gallatin R nr Gateway May-Sep 271 61 345 219 445
GLGM8
Gallatin R nr Gateway May-Sep 271 61 345 219 445
GLGM8N
Gallatin R at Logan May-Sep 231 52 333 183 447
LOGM8
Gallatin R at Logan May-Sep 377 64 463 326 589
LOGM8N
Missouri R at Toston May-Sep 1195 68 1639 1071 1766
TOSM8
Missouri R at Toston May-Sep 1804 72 2210 1668 2520
TOSM8N
Missouri R at Fort Benton May-Sep 1492 57 1683 1389 2635
FBNM8
Missouri R at Fort Benton May-Sep 2648 73 3205 2376 3640
FBNM8N
Missouri R nr Virgelle May-Sep 1585 54 1822 1478 2950
VRGM8
Missouri R nr Virgelle May-Sep 3037 75 3850 2740 4035
VRGM8N
Missouri R nr Landusky May-Sep 1695 53 1952 1535 3170
LDKM8
Missouri R nr Landusky May-Sep 3236 75 4034 2887 4325
LDKM8N
Missouri R below Fort Peck Dam May-Sep 1773 54 2068 1557 3270
FPKM8
Missouri R below Fort Peck Dam May-Sep 3335 74 4127 2950 4530
FPKM8N
Gibson Resvr Inflow May-Sep 335 82 479 280 409
AGSM8
Gibson Resvr Inflow May-Sep 334 82 479 279 409
AGSM8N
Marias R nr Shelby May-Sep 280 75 432 210 372
SHLM8
Marias R nr Shelby May-Sep 336 79 486 263 425
SHLM8N
Musselshell R at Harlowton May-Sep 12 16 18 9 71
HLWM8
Musselshell R at Harlowton May-Sep 17 19 23 13 85
HLWM8N
Yellowstone R at Yellowstone Lk May-Sep 597 76 642 500 783
YLOW4
Yellowstone R at Yellowstone Lk May-Sep 753 104 841 634 722
YLOW4N
Yellowstone R at Corwin Sprgs May-Sep 1236 66 1447 1048 1876
CORM8
Yellowstone R at Corwin Sprgs May-Sep 1483 76 1714 1277 1958
CORM8N
Yellowstone R at Livingston May-Sep 1366 64 1641 1158 2147
LIVM8
Yellowstone R at Livingston May-Sep 1682 73 1952 1451 2304
LIVM8N
Yellowstone R at Billings May-Sep 1869 49 2448 1557 3805
BILM8
Yellowstone R at Billings May-Sep 2808 62 3389 2455 4515
BILM8N
Yellowstone R at Miles City May-Sep 3077 58 4133 2608 5320
MILM8
Yellowstone R at Miles City May-Sep 5196 73 6509 4433 7115
MILM8N
Yellowstone R at Sidney May-Sep 3072 57 4286 2528 5345
SIDM8
Yellowstone R at Sidney May-Sep 5453 73 6902 4612 7435
SIDM8N
Boulder R at Big Timber May-Sep 133 42 175 107 320
BTMM8
Boulder R at Big Timber May-Sep 176 49 216 150 362
BTMM8N
Stillwater R nr Absarokee May-Sep 306 60 387 258 512
SRAM8
Stillwater R nr Absarokee May-Sep 364 64 443 316 571
SRAM8N
Clks Fk Yellowstone R nr Belfry May-Sep 337 57 440 284 594
BFYM8
Clks Fk Yellowstone R nr Belfry May-Sep 408 61 511 354 664
BFYM8N
Bighorn R nr St. Xavier May-Sep 894 73 1474 795 1227
STXM8
Bighorn R nr St. Xavier May-Sep 1981 88 2752 1541 2240
STXM8N
Little Bighorn R nr Hardin May-Sep 67 60 114 54 112
HRDM8
Little Bighorn R nr Hardin May-Sep 67 60 113 54 112
HRDM8N
Tongue R nr Dayton May-Sep 59 66 84 45 90
DAYW4
Tongue R nr Dayton May-Sep 65 67 89 50 96
DAYW4N
Tongue R nr Decker May-Sep 98 46 170 63 215
DSLM8
Tongue R nr Decker May-Sep 140 64 212 103 220
DSLM8N
Tongue R Resvr Inflow May-Sep 99 46 176 64 216
DKRM8
Tongue R Resvr Inflow May-Sep 141 62 218 104 227
DKRM8N
Powder R at Moorhead May-Sep 81 40 264 57 200
MHDM8
Powder R at Moorhead May-Sep 114 48 300 84 240
MHDM8N
Powder R nr Locate May-Sep 139 62 325 106 223
LOCM8
Powder R nr Locate May-Sep 176 67 362 131 263
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 1981-2010.
The 50%, 10% and 90% columns indicate the probability that the
actual volume will exceed the forecast for the valid time perion
for more information, please visit: www.weather.gov/mbrfc/water
