Standardized Precipitation Index Table

Belle Fourche Drainage Climate Division

Wyoming, Climate Division 06

Precipitation Data Table

Time Scale in Months (As of the end of Jan. 2026)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 0.4 1.12 1.42 4.36 4.96 6.36 9.14 11.89 14.82 17.04 18.15 18.42 19.84 23.18 31.92 38.47 51.08 67 78.84 90.81
Accumulated Precipitation Departure from Normal (in.) -0.19 -0.09 -0.46 1.31 0.61 0.67 1.62 1.63 1.79 2.25 2.36 2.01 1.58 1.12 -0.85 0.05 1.95 1.5 -3.05 -7.5
Accumulated Precipitation Percent of Average 68 92 76 143 114 112 122 116 114 115 115 112 109 105 97 100 104 102 96 92
Accumulated Precipitation Percentile (non-exceedance) 31.3 48.3 26.5 89 70.9 69.3 81.3 76.8 74.5 77.5 78 74.7 69.6 63.8 44.7 52.2 64 59.7 36.6 21.1
Standardized Precipitation Index -0.49 -0.04 -0.63 1.23 0.55 0.5 0.89 0.73 0.66 0.76 0.77 0.66 0.51 0.35 -0.13 0.05 0.36 0.25 -0.34 -0.8