Standardized Precipitation Index Table

Southwest Highlands (R) Climate Division

Idaho, Climate Division 06

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.) 1.74 2.32 3.3 4.01 5.76 6 7.52 8.28 8.98 9.31 9.56 10.81 15.21 19.37 22.73 32.29 39.12 52.24 64.09 75.17
Accumulated Precipitation Departure from Normal (in.) 0.41 -0.37 -0.66 -1.46 -1.19 -2.3 -1.77 -1.66 -1.37 -1.47 -2.38 -2.73 -2.29 -2.48 -4.36 -3.1 -1.52 -1.95 -3.65 -6.14
Accumulated Precipitation Percent of Average 131 86 83 73 83 72 81 83 87 86 80 80 87 89 84 91 96 96 95 92
Accumulated Precipitation Percentile (non-exceedance) 76.5 38.9 30.9 16.3 26.6 12.3 20.1 21.4 25.6 24.1 13.3 12.5 19.3 23 11.9 25 39.1 38 29.3 19.6
Standardized Precipitation Index 0.72 -0.28 -0.5 -0.98 -0.63 -1.16 -0.84 -0.79 -0.66 -0.7 -1.11 -1.15 -0.87 -0.74 -1.18 -0.68 -0.28 -0.31 -0.54 -0.86