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Percent of normal precipitation required from mid-December through the end of the water year in September in order to reduce rainfall deficits. (left) All climate divisions would need more than 100 percent of normal precipitation just to emerge from the lowest 20% of values (20th percentile) for all four-year periods in the historical record. (right) To be restored to the middle of the historical pack (50th percentile), several would need to exceed all-time precipitation records by many inches. Maps by NOAA Climate.gov, based on analysis of Climate Division data by Rich Tinker, NOAA Climate Prediction Center.