Maps: Precipitation All Strong El Niño Month by Month

Shown above are national-scale composites of monthly precipitation during historical strong El Niño winter seasons, expressed as anomalies from long-term averages. Strong El Niño conditions may provide some guidance for preparing seasonal precipitation outlooks in parts of the U.S. at certain times of the year, but El Niño is not the only factor influencing the climate system. Each winter season is unique, and past performance should not be taken as a guarantee of future outcomes.