Standardized Precipitation Index Table

West Olympic Coastal Climate Division

Washington, Climate Division 01

Precipitation Data Table

Time Scale in Months (As of the end of Jul. 2020)
1 2 3 4 5 6 7 8 9 10 11 12 15 18 24 30 36 48 60 72
Accumulated Precipitation (in.) 0.7 5.09 10.88 14.38 21.57 32.8 64.33 79.01 84.25 94.36 102.97 104.77 110.23 128 193.4 227.59 303.08 438.68 564.17 663
Accumulated Precipitation Departure from Normal (in.) -1.01 0.04 1.08 -3.04 -7.49 -8.79 6.45 3.9 -7.07 -7.42 -3.62 -3.95 -8.28 -22.38 -24.07 -31.68 -23.27 3.54 20.58 11.3
Accumulated Precipitation Percent of Average 41 101 111 83 74 79 111 105 92 93 97 96 93 85 89 88 93 101 104 102
Accumulated Precipitation Percentile (non-exceedance) 26.3 57.4 66.4 26.9 13 15.5 74.1 63.9 33.4 34.2 43.4 42.5 32.7 12.2 16.3 11.9 23.2 55 69.8 60.7
Standardized Precipitation Index -0.63 0.19 0.42 -0.62 -1.12 -1.02 0.65 0.36 -0.43 -0.41 -0.17 -0.19 -0.45 -1.17 -0.98 -1.18 -0.73 0.12 0.52 0.27