Standardized Precipitation Index Table

Appalachian Mountain Climate Division

Maryland, Climate Division 07

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.) 3.53 6.46 11.22 14.96 17.54 19.41 23.38 26.41 29.47 32.57 34.33 36.83 43.3 52.79 75.56 86.72 111.94 150.87 191.28 259.97
Accumulated Precipitation Departure from Normal (in.) 0.25 0.75 2.75 3.65 3.55 2.4 3.06 2.48 1.83 1.04 -1.07 -1.88 -3.86 -2.97 -1.94 -7.84 -4.35 -4.23 -2.58 27.33
Accumulated Precipitation Percent of Average 107 113 132 132 125 114 115 110 107 103 97 95 92 95 98 92 96 97 99 112
Accumulated Precipitation Percentile (non-exceedance) 62.3 69.3 90.5 91.1 87 76.6 78.8 72.8 67 60.3 44.1 38.5 27.4 34.4 41.9 19.4 33.9 36.4 42.9 97.1
Standardized Precipitation Index 0.31 0.5 1.31 1.35 1.13 0.73 0.8 0.61 0.44 0.26 -0.15 -0.29 -0.6 -0.4 -0.2 -0.86 -0.41 -0.35 -0.18 1.9