Standardized Precipitation Index Table

All Climate Division

Rhode Island, Climate Division 01

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.) 10.14 12.4 20.63 28.52 30.75 34.16 41.73 46.17 53.91 57.77 61.49 65.49 77.87 92.59 112.39 135.03 166.04 210.07 263.1 322.74
Accumulated Precipitation Departure from Normal (in.) 5.8 4.57 8.86 12.45 10.52 10.08 13.89 14.33 18.67 19.08 19.3 19.19 19.87 22.32 19.98 18.63 27.48 25.46 32.58 46.35
Accumulated Precipitation Percent of Average 234 158 175 178 152 142 150 145 153 149 146 141 134 132 122 116 120 114 114 117
Accumulated Precipitation Percentile (non-exceedance) 98.5 95.5 99.6 99.9 99.2 98.1 99.4 99.2 99.8 99.8 99.7 99.5 99.4 99.2 97 94 97.8 94.4 95.9 98.5
Standardized Precipitation Index 2.18 1.7 2.62 3.06 2.4 2.08 2.5 2.4 2.91 2.82 2.74 2.6 2.5 2.41 1.87 1.55 2.01 1.59 1.74 2.18