Standardized Precipitation Index Table

Central Mountains Climate Division

Idaho, Climate Division 04

Precipitation Data Table

Time Scale in Months (As of the end of Mar. 2024)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 3.78 8.2 11.92 15.01 18 19.63 20.93 23.52 23.65 26.71 29.19 31.8 41.37 52.54 65.78 86.63 93.24 124.51 156.65 188.32
Accumulated Precipitation Departure from Normal (in.) 0.2 0.85 -0.08 -1.61 -2.77 -3.68 -3.96 -2.36 -3.16 -2.36 -2.61 -2.73 -5.16 -5.35 -3.32 -5.79 -10.38 -13.67 -16.16 -19.17
Accumulated Precipitation Percent of Average 106 112 99 90 87 84 84 91 88 92 92 92 89 91 95 94 90 90 91 91
Accumulated Precipitation Percentile (non-exceedance) 60.7 68.3 52.4 36.7 30 23.3 22.1 33.1 27 33.3 32.6 31.7 18.6 21.6 33.9 25.3 12.4 9.6 8.4 6.3
Standardized Precipitation Index 0.27 0.48 0.06 -0.34 -0.53 -0.73 -0.77 -0.44 -0.61 -0.43 -0.45 -0.48 -0.89 -0.79 -0.42 -0.67 -1.16 -1.31 -1.38 -1.53