Standardized Precipitation Index Table

Northwest Plateau Climate Division

Pennsylvania, Climate Division 10

Precipitation Data Table

Time Scale in Months (As of the end of Jul. 2020)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 3.76 7.02 10.64 14.69 19.54 23.28 26.57 30.34 33.27 38.42 41.47 45.72 64.22 74.74 102.31 129.94 150.89 204.61 246.03 289.26
Accumulated Precipitation Departure from Normal (in.) -0.59 -1.71 -2.05 -1.64 -0.17 1.02 1.21 1.69 1.18 2.84 2.18 2.65 8.44 9.42 16.16 21.6 21.76 32.52 31.06 31.35
Accumulated Precipitation Percent of Average 86 80 84 90 99 105 105 106 104 108 106 106 115 114 119 120 117 119 114 112
Accumulated Precipitation Percentile (non-exceedance) 37.9 23.1 24.3 31.6 50.1 63.3 64.9 69.1 63.1 75.5 69.9 72.1 92.4 93.2 98 99.2 98.4 99.6 98.8 98
Standardized Precipitation Index -0.31 -0.74 -0.7 -0.48 0 0.34 0.38 0.5 0.33 0.69 0.52 0.59 1.43 1.49 2.05 2.41 2.14 2.65 2.27 2.05