Standardized Precipitation Index Table

Southwest Climate Division

Iowa, Climate Division 07

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.) 2.08 5.15 6.74 7.12 7.28 8.1 11.65 13.53 14.39 18.41 21.53 25.54 39 42.21 57.69 68.77 81.22 114.16 139.74 173.98
Accumulated Precipitation Departure from Normal (in.) -2.28 -2.21 -2.53 -3.16 -3.85 -4.11 -2.13 -2.75 -5.55 -5.65 -6.43 -7.2 -3.03 -2.75 -7.83 -8.89 -17.04 -16.98 -24.3 -23.05
Accumulated Precipitation Percent of Average 48 70 73 69 65 66 85 83 72 77 77 78 93 94 88 89 83 87 85 88
Accumulated Precipitation Percentile (non-exceedance) 11.5 21.9 22.2 16.4 10.9 10.8 31.4 28.5 12.8 14.4 14.6 12.5 36.1 38.1 20.3 19.7 6.4 10.5 5.5 8.8
Standardized Precipitation Index -1.2 -0.77 -0.77 -0.98 -1.23 -1.24 -0.48 -0.57 -1.14 -1.06 -1.06 -1.15 -0.35 -0.3 -0.83 -0.85 -1.52 -1.25 -1.59 -1.35