Standardized Precipitation Index Table

South Central Climate Division

Iowa, Climate Division 08

Precipitation Data Table

Time Scale in Months (As of the end of Apr. 2026)
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 8.23 8.44 9.48 10.48 11.56 13.99 16.03 18.65 26.89 32.73 35.72 40.97 46.8 70.62 82.13 98.76 127.8 164.35 196.26
Accumulated Precipitation Departure from Normal (in.) 2.92 2.79 1.86 1.8 1.5 0.71 0.51 -1.29 -2.68 1.58 2.6 1.22 -0.09 1.44 1.61 2.38 -4.64 -10.12 -8.14 -10.82
Accumulated Precipitation Percent of Average 187 151 128 123 117 107 104 93 87 106 109 104 100 103 102 103 96 93 95 95
Accumulated Precipitation Percentile (non-exceedance) 94.6 89 80.6 79.4 74.9 62.8 59.2 40.9 30.6 63.6 68.5 59.6 51.9 59.7 58.3 60.7 35.9 24.1 31.5 27.7
Standardized Precipitation Index 1.61 1.23 0.86 0.82 0.67 0.33 0.23 -0.23 -0.51 0.35 0.48 0.24 0.05 0.24 0.21 0.27 -0.36 -0.7 -0.48 -0.59