Snowpack
Snowpack over the State varied from above normal to well below normal. The
northwest portion of the State is generally slightly below normal with some
individual locations well above normal The Wind River drainage is near
normal, while the remaining portions of the northwest part of Wyoming are
10-15 percent below normal. SWE in the northeast part of Wyoming is 5-10
percent below normal. The southeast portion of the State ended up near
normal to 85 percent of normal at the end of March. Generally, the
southwest part of the State is average to slightly below average; the
Henrys Fork drainage was about 34 percent above normal, and the upper Green
river basins about 12 percent below normal. The Bear River drainage
appears to have just below normal SWE.
Precipitation
Most basins across Wyoming received above average precipitation. Nine of
the 13 basins were above average for the month of March. March
precipitation in the Black Hills was 14 percent below average for the month
compared to 232 percent above average last month. The following table
displays the major river basins and their departure from normal.
| Basin | Departure from normal | Basin | Departure from normal |
| Snake River | +21% | Upper North Platte River | +08% |
| Yellowstone & Madison | +12% | Lower North Platte River | -02% |
| Wind River | +47% | Little Snake River | +09% |
| Bighorn | -05% | Upper Green River | +41% |
| Shoshone & Clarks Fork | +13% | Lower Green River | +37% |
| Powder & Tongue River | -11% | Upper Bear River | +60% |
| Belle Fourche & Cheyenne | -14% |
Streams
Runoff is expected to vary from average to just below average across the
state. The northwestern part of the state is expected to have yields
varying from average to about 10 percent below average. The northeast
portion of Wyoming varies from near average to about 15 percent below
average. In most cases, the southeast portion of the state will be near
average to about 15 percent below normal (as much as 23 percent below
normal in the lower portion of the Platte River drainage). The southwest
varies from above average on the Blacks Fork drainage to 82 percent of
average for inflow into Fontenelle Reservoir and 10- 15 percent below
average on the Bear River drainage.
Reservoirs
Reservoir storage varies from well below to well above average, however,
the majority are above average for this time of the year. Even a below
average runoff should fill most reservoirs. See following table for
further information about reservoir storage.
Major Reservoirs in Wyoming
B A S I N W I D E
R E S E R V O I R S U M M A R Y
FOR THE END OF MARCH 1998
BASIN AREA CURRENT AS LAST YR AS AVERAGE AS CURRENT AS CURRENT AS
RESERVIOR % CAPACITY % CAPACITY % CAPACITY % AVERAGE % LAST YR
--------------------------------------------------------------------------------
ALCOVA 86 85 88 98 101
ANGOSTURA 99 99 90 109 100
BELLE FOURCHE 101 96 73 137 104
BIG SANDY 64 70 52 124 93
BIGHORN LAKE 63 56 59 108 113
BOYSEN 86 77 89 96 112
BUFFALO BILL 80 66 56 144 122
BULL LAKE 62 54 55 114 116
DEERFIELD 101 96 89 113 105
EDEN 30 52 40 74 57
ENNIS LAKE 72 69 81 89 105
FLAMING GORGE AVERAGE NOT ESTABLISHED
FONTENELLE 34 35 46 73 96
GLENDO 89 95 83 107 94
GRASSY LAKE 50 88 74 68 57
GUERNSEY 69 63 47 145 109
HEBGEN LAKE 70 62 65 106 112
JACKSON LAKE 77 65 56 137 117
KEYHOLE 94 94 56 170 101
PACTOLA 98 97 85 115 101
PALISADES 70 28 72 97 248
PATHFINDER 98 89 61 161 110
PILOT BUTTE 69 74 68 101 93
SEMINOE 75 63 36 208 120
SHADEHILL 78 103 78 101 76
TONGUE RIVER 14 38 53 26 37
VIVA NAUGHTON RES NO REPORT
WHEATLAND #2 71 63 49 144 113
WOODRUFF NARROWS AVERAGE NOT ESTABLISHED
GLENDO PROJECT USERS 92 92 69 133 100
KENDRICK PROJECT 78 77 68 116 102
NORTH PLATTE PROJ 101 86 64 159 118
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