Standardized Precipitation Index Table

Northwest Climate Division

Connecticut, Climate Division 01

Precipitation Data Table

Time Scale in Months (As of the end of May 2025)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 7.17 10.49 14.23 17.27 18.41 22.98 25.78 26.22 27.23 34.76 41.06 44.64 61.69 79.93 117.86 142.65 164.34 221.56 265 309.29
Accumulated Precipitation Departure from Normal (in.) 3.01 2.24 1.85 1.58 -0.91 -0.42 -1.71 -5.31 -8.72 -5.67 -3.8 -4.36 0.33 7.53 19.82 21.27 17.42 25.85 20.6 16.15
Accumulated Precipitation Percent of Average 172 127 115 110 95 98 94 83 76 86 92 91 101 110 120 118 112 113 108 106
Accumulated Precipitation Percentile (non-exceedance) 93.2 81.8 73.7 69.9 43 48.5 37.9 16.4 5.8 19.7 30.8 29.2 53.4 80.3 95.5 95.2 89.4 94 86.5 78.4
Standardized Precipitation Index 1.49 0.91 0.63 0.52 -0.18 -0.04 -0.31 -0.98 -1.57 -0.85 -0.5 -0.55 0.08 0.85 1.7 1.67 1.25 1.55 1.1 0.79