Standardized Precipitation Index Table

West Central Lower Climate Division

Michigan, Climate Division 05

Precipitation Data Table

Time Scale in Months (As of the end of May 2025)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 4.17 6.41 10.77 11.74 13.33 15.95 19.43 20.68 22.88 26.47 29.44 35.92 45.97 50.89 67.7 82.38 103.64 140.87 168.25 214.25
Accumulated Precipitation Departure from Normal (in.) 1.05 0.38 2.54 1.86 1.31 1.65 2.26 0.32 -0.85 -0.38 -0.21 3.12 4.97 3.75 2.07 2.43 5.18 9.57 4.1 17.17
Accumulated Precipitation Percent of Average 133 106 131 119 111 112 113 102 96 99 99 110 112 108 103 103 105 107 102 109
Accumulated Precipitation Percentile (non-exceedance) 79.5 61.8 87.1 79.6 71.2 73.3 76.2 55.8 44.5 49 50.4 74.7 82.5 74.7 62.4 62.8 71.3 79.1 62.4 85.1
Standardized Precipitation Index 0.82 0.3 1.13 0.83 0.56 0.62 0.71 0.15 -0.14 -0.03 0.01 0.66 0.93 0.67 0.31 0.33 0.56 0.81 0.32 1.04