Scientists are warning that conditions in the Pacific Ocean could lead to a powerful El Niño weather pattern that is developing earlier than expected, potentially bringing conditions to Illinois that will continue into winter.
In a forecast discussion Thursday, the National Oceanic and Atmospheric Administration’s Climate Prediction Center estimated an 82 percent chance that El Niño conditions will develop as soon as this month and a 96 percent chance they will persist into February 2027.
NOAA’s latest May through July outlook for Illinois shows a 33 percent to 40 percent chance of above-average temperatures. Forecasts also put Illinois at having an equal chance of being above or below normal seasonal precipitation.
A historically strong “super El Niño” can disrupt weather patterns worldwide, often bringing heavier rains and flooding to some regions while worsening drought and heat in others. Meteorologists say a major event in 2026 could contribute to record global temperatures, alter hurricane activity, fuel wildfires, and strain food and water supplies in vulnerable areas.
NOAA said it is still too early to know whether it will reach “super El Niño” strength. Spring forecasts are notoriously uncertain because ocean and atmospheric conditions can change rapidly.
Thursday’s forecast discussion contrasts with a February outlook in which NOAA said a weakening La Niña in the tropical Pacific was expected to transition to ENSO-neutral conditions by spring, likely lasting through the summer.
AccuWeather, The Weather Channel and the Old Farmer’s Almanac also said in their February outlooks that a weakening La Niña pattern would transition to neutral conditions in the spring, but did not forecast a developing El Niño.
More recent forecasts, including one last month from the private weather company AccuWeather, said a strong El Niño was expected to put Illinois at “high” risk of destructive lines of thunderstorms known as derechos. A derecho is much more powerful than a typical thunderstorm and is sometimes called an “inland hurricane” because of the widespread wind damage it can cause.
AccuWeather meteorologists said the Northeast and mid-Atlantic can expect a warmer summer with intense heat and potential localized flooding from thunderstorms. The South and Southeast may see frequent storms and above-average rain, while the Midwest and Ohio Valley face heat and severe, damaging storms. Hot, dry conditions in the West, particularly the Southwest, increase drought and wildfire risks.
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