Standardized Precipitation Index Table

West Central Climate Division

Oklahoma, Climate Division 04

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.) 1.6 2.09 2.59 3.23 3.27 3.82 4.99 7.08 12.24 13.81 19.63 23.07 30.45 38.19 50.89 60.67 84.86 106.66 127.55 150.53
Accumulated Precipitation Departure from Normal (in.) -0.98 -2.15 -2.64 -2.79 -3.8 -4.66 -5.84 -6.44 -3.9 -4.7 -2.46 -3.2 -1.07 3.36 -1.72 -0.48 5.89 1.37 -4.11 -7.52
Accumulated Precipitation Percent of Average 62 49 50 54 46 45 46 52 76 75 89 88 97 110 97 99 107 101 97 95
Accumulated Precipitation Percentile (non-exceedance) 31.7 15.1 11 13 6.9 5.1 3.5 3.8 18.8 16.3 35.1 30 45.4 71.4 43.7 49.8 73 56.1 39.1 31.2
Standardized Precipitation Index -0.47 -1.03 -1.23 -1.13 -1.49 -1.63 -1.81 -1.77 -0.89 -0.98 -0.38 -0.52 -0.11 0.57 -0.16 -0.01 0.61 0.15 -0.28 -0.49