Snowpack
Less than average, and so some cases much less than average, snowfall has occurred this past month. SWE is generally below average for the entire State. SWE in the northwestern portion of the State is now at 79 percent of average (155 percent of last year). Northeast Wyoming SWE is currently about 67 percent of average (86 percent of last year). The southeast portion is currently about 60 percent of average SWE (78 percent of last year). And the southwest is about 76 percent of average (112 percent of last year).
Precipitation
January precipitation was below normal over the entire State. Some of the State had a very severe shortage of precipitation. The southwest portion of the State was near 50 percent below average for the month of January. The southeast was also near 50 percent, while the rest of the State received from 9 to 40 percent below average. The following table displays the major river basins and their departure from normal for this month.
| Basin | Departure from normal | Basin | Departure from normal |
| Snake River | -28% | Upper North Platte River | -48% |
| Yellowstone & Madison | -10% | Lower North Platte River | -51% |
| Wind River | -21% | Little Snake River | -52% |
| Bighorn | -33% | Upper Green River | -40% |
| Shoshone & Clarks Fork | -09% | Lower Green River | -48% |
| Powder & Tongue River | -29% | Upper Bear River | -50% |
| Belle Fourche & Cheyenne | -37% |
Streams
Stream flow yield is expected to be below average across the State. Most probable yield for the State is forecast to be about 58 percent of average. The northwest part of the State is expected to yield about 67 percent of normal -- yield estimates vary from 45 to 90 percent of normal. Yield from the northeast portion of Wyoming will be below average (about 53 percent of average) -- yield estimates vary from 47 to 63 percent of average for the various forecast points. The southeast portion of the state will be about 40 percent of normal -- yield estimates range from 8 to 67 percent of normal. The southwest portion of Wyoming varies from 55 to 81 percent of average -- mean estimated yield for the forecast points in southwest Wyoming is about 70 percent of average.
Reservoirs
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 JANUARY 2002
BASIN AREA CURRENT AS LAST YR AS AVERAGE AS CURRENT AS CURRENT AS
RESERVIOR % CAPACITY % CAPACITY % CAPACITY % AVERAGE % LAST YR
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ALCOVA 35 46 74 47 77
ANGOSTURA 81 72 80 101 113
BELLE FOURCHE 76 81 57 133 94
BIG SANDY 35 46 74 47 77
BIGHORN LAKE 35 46 74 47 77
BOYSEN 35 46 74 47 77
BUFFALO BILL 35 46 74 47 77
BULL LAKE 35 46 74 47 77
DEERFIELD 98 99 84 116 99
EDEN 35 46 74 47 77
ENNIS LAKE 35 46 74 47 77
FLAMING GORGE 76 80 79 96 95
FONTENELLE 35 46 74 47 77
GLENDO 35 46 74 47 77
GRASSY LAKE 62 84 78 80 74
GUERNSEY 35 46 74 47 77
HEBGEN LAKE 35 46 74 47 77
JACKSON LAKE 17 75 58 30 23
KEYHOLE 80 82 53 151 97
PACTOLA 96 100 83 115 96
PALISADES 35 46 74 47 77
PATHFINDER 35 46 74 47 77
PILOT BUTTE 35 46 74 47 77
SEMINOE 79 78 63 124 101
SHADEHILL 63 49 60 104 127
VIVA NAUGHTON RES 35 46 74 47 77
WHEATLAND #2 35 46 74 47 77
WOODRUFF NARROWS 35 46 74 47 77
GLENDO PROJECT USE 35 46 74 47 77
KENDRICK PROJECT 35 46 74 47 77
NORTH PLATTE PROJ 35 46 74 47 77
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