Standardized Precipitation Index Table

West Upper Climate Division

Michigan, Climate Division 01

Precipitation Data Table

Time Scale in Months (As of the end of Jul. 2020)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 6.27 9.65 11.82 14.78 17.5 18.24 20.55 24.41 26.94 31.35 37.08 39.67 49.11 58.55 78.92 93.27 113.26 152.3 187.81 220.96
Accumulated Precipitation Departure from Normal (in.) 2.72 2.48 1.49 2.12 3.09 2.47 3.15 5.18 5.31 6.88 9.03 8.32 7.44 11.45 16.26 14.89 19.38 27.18 31.53 33.54
Accumulated Precipitation Percent of Average 177 135 114 117 121 116 118 127 125 128 132 127 118 124 126 119 121 122 120 118
Accumulated Precipitation Percentile (non-exceedance) 96.1 90.2 76.7 81.4 87.7 81.6 85.7 95 95 97.2 98.5 97 93.4 98 99.4 98.2 99.4 99.9 99.9 99.9
Standardized Precipitation Index 1.77 1.29 0.73 0.89 1.16 0.9 1.07 1.65 1.65 1.91 2.17 1.88 1.5 2.06 2.54 2.1 2.5 2.98 3.13 3.13