Statistical shading percentiles are calculated from period of record (POR) data, excluding the current water year. Percentile categories range from: minimum to 10th percentile , 10th - 30th , 30th - 70th , 70th - 90th , and 90th - maximum.
For more information visit: 30-Year Hydroclimatic Normals
Updated: Friday, Oct 31, 2025 11 AM CST