How Extreme Weather and El Niño May Influence Fall Colors in Chicago

Impact of Extreme Weather and El Niño on Fall Colors in Chicago

The changing of the seasons brings anticipation for nature enthusiasts, particularly in places like Chicago where vivid fall colors attract many visitors. Recent analysis by tree experts at The Morton Arboretum indicates significant weather factors, including the historic El Niño, poised to shape this season's foliage.

El Niño's Influence

August saw Chicago experiencing extreme weather patterns, from severe drought to unexpected showers. El Niño, characterized by warmer Pacific ocean temperatures, is forecasted to maintain warmer than average conditions into October, November, and December. As Dr. Christy Rollinson, a senior scientist in forest ecology at the Arboretum, suggests, "The effects of El Niño are likely to compress the fall color season—leaves may change all at once rather than gradually."

Drawing from the Arboretum's seasoned tracking of weather, it appears that drought—the first major climate condition this summer—might typically signal an early onset of fall colors. However, this year, the situation is more nuanced. On the one hand, species such as the autumn blaze maple have already begun showing their colors ahead of usual timelines. On the other, an abundance of rainfall over the last few months acts as a counterbalance to the early effects of drought.