Standardized Precipitation Index Table

All Climate Division

Rhode Island, Climate Division 01

Precipitation Data Table

Time Scale in Months (As of the end of Sep. 2020)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 1.08 2.85 4.58 7.42 10.6 16 20.47 23.77 25.27 32.58 35.7 42.76 53.08 69.03 103.25 128.67 158.57 207.82 247.86 292.52
Accumulated Precipitation Departure from Normal (in.) -2.59 -4.82 -6.44 -7.05 -7.37 -6.09 -5.93 -6.13 -8.53 -5.48 -6.55 -3.3 -4.06 0.83 11.14 14.45 20.51 23.98 18.35 17.25
Accumulated Precipitation Percent of Average 29 37 42 51 59 72 78 79 75 86 84 93 93 101 112 113 115 113 108 106
Accumulated Precipitation Percentile (non-exceedance) 5.2 2 0.4 1.3 2.2 7.4 10.3 10.5 4.4 16.2 13.9 32.4 30.9 55.5 86.4 88.9 93.6 93.2 84.9 80.7
Standardized Precipitation Index -1.62 -2.05 -2.62 -2.23 -2.01 -1.45 -1.27 -1.26 -1.71 -0.99 -1.08 -0.46 -0.5 0.14 1.1 1.22 1.52 1.49 1.03 0.87