Standardized Precipitation Index Table

Southeastern Climate Division

Montana, Climate Division 07

Precipitation Data Table

Time Scale in Months (As of the end of Feb. 2024)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 0.39 0.66 0.85 0.97 2.63 4.68 6.75 7.6 12.32 15.45 15.97 16.53 18.25 20.75 31.97 35.8 41.91 52.33 73.29 90.39
Accumulated Precipitation Departure from Normal (in.) -0.05 -0.25 -0.52 -0.91 -0.24 0.6 1.46 0.67 2.66 3.44 2.63 2.45 2.79 2.59 3.83 3.6 -0.27 -3.95 2.88 5.93
Accumulated Precipitation Percent of Average 88 72 62 52 92 115 128 110 128 129 120 117 118 114 114 111 99 93 104 107
Accumulated Precipitation Percentile (non-exceedance) 48 27.7 12.7 3.9 43.3 71.1 84.2 67.7 88 88.3 80.9 79.6 81.9 78.1 81.5 79 49.7 28 66.1 76.4
Standardized Precipitation Index -0.05 -0.59 -1.14 -1.77 -0.17 0.55 1 0.46 1.17 1.19 0.88 0.83 0.91 0.78 0.9 0.81 -0.01 -0.58 0.42 0.72