Summer heat is expected to last well into autumn across much of America, along with an increased risk of wildfires and severe weather, according to a long-range forecast from AccuWeather.
“Fall is going to feel more like an extended summer for millions of Americans this year,” AccuWeather Lead Long-Range Expert Paul Pastelok said in a release. “Much of the country will experience a delayed transition to cooler temperatures this year, following a summer with intense heat. We’ve seen record-high temperatures shattered in several cities across California, Nevada, Oregon, Utah and North Carolina this summer. We could see more record temperatures this fall.”
Specifically, the AccuWeather 2024 U.S. Fall Forecast predicts that temperatures are expected to hover 1 to 3 degrees or more above the historical average across much of the country, most of the time, from September through November. The highest temperature departures are expected across parts of the Great Lakes region, the Midwest and the Rockies.
In contrast, the only areas where above-historical average temperatures are not expected this autumn are in Florida, parts of coastal Texas, Louisiana, Georgia, South Carolina and coastal areas along California, Oregon and Washington. And the Pacific Northwest is the only region where experts are predicting an early arrival of fall-like weather, including some early-season storms.
The transition to cooler fall air is typically known for sparking the “second severe weather season” as waves of cold air begin to dive southward, clashing with the warm and humid air across much of the central and eastern United States.
That pattern could be exacerbated this year, as 2024 has been an extremely active year for severe weather in the United States, and the trend could continue well into autumn. “There have been more than 1,400 tornado reports this year. That number is already above the historical average number of tornadoes typically reported in a year,” said Pastelok. “We could see even more tornadoes from hurricanes and tropical storms making landfall this fall.”
A main factor pushing the noticeable shift in fall temperatures is emissions from the burning of fossil fuels and our warming atmosphere, AccuWeather Senior Meteorologist and Climate Expert Brett Anderson said. That climate change is also impacting agriculture and fall tourism dates.
“We are already seeing a later end to the growing season. The first freeze of the season in many regions is now several days to a week or more later than the typical first freeze we saw just a few decades ago. Warmer nights also slow the breakdown of green chlorophyll in leaves, which has led to a delay in peak foliage in many areas, as well as less vibrant fall colors,” explained Anderson. “Warmer, more humid and wetter conditions in the summer months can promote the growth of fungi and also allow more tree-damaging insects to survive longer into the fall season, putting additional stress on trees.”
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