Standardized Precipitation Index Table

Northern Climate Division

Delaware, Climate Division 01

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.) 2.47 4.76 6.27 8.55 11.56 13.59 16 18.11 19.7 25.87 28.8 35.84 45.8 52.84 68.11 98.18 121.25 161.95 201.43 253.09
Accumulated Precipitation Departure from Normal (in.) -1.12 -2.64 -4.09 -5.13 -5.69 -6.78 -7.56 -9.14 -11.91 -10.16 -11.14 -7.77 -8.2 -11.27 -19.25 -9.77 -10.01 -13.14 -17.45 -9.67
Accumulated Precipitation Percent of Average 69 64 61 62 67 67 68 66 62 72 72 82 85 82 78 91 92 92 92 96
Accumulated Precipitation Percentile (non-exceedance) 22.8 9.8 3.4 2.7 4.5 4.2 3.7 2.8 1 3.6 3.6 12.5 13 7.8 2.3 17.2 20.3 17.1 13.5 29.8
Standardized Precipitation Index -0.75 -1.29 -1.83 -1.93 -1.69 -1.73 -1.78 -1.92 -2.32 -1.8 -1.8 -1.15 -1.13 -1.42 -2 -0.95 -0.83 -0.95 -1.1 -0.53