Autumn is less than a month away, but don’t expect calm, crisp days across the board. While some regions will slide into sweater weather, others could be dealing with wildfires, lingering summer heat or tropical storms that spin up close to home.
As AccuWeather reports, meteorological fall starts on Monday, Sept. 1, while astronomical autumn starts on the equinox at 2:19 p.m. EDT on Monday, Sept. 22. But when will it actually feel like fall when you step outside?
Temperature Trends: Summer Warmth Lingers, but Cold Blasts are Lurking
Warm, humid air will hold firm across the eastern United States through the start of autumn, delaying the true arrival of fall-like weather conditions. However, the warmest weather, compared to the historical average, will be focused on areas from California to Texas and northward into Oregon and Idaho.
Chilly transitions will have people reaching for hoodies, pants and heavier coats in late October and into November as intrusions of cold air become more frequent. Meanwhile, warm air will be persistent across the Southeast and Southwest well into the second half of fall.
Cold spots: The cold air will first arrive and be most pronounced in North Dakota, South Dakota, Minnesota, Iowa, Wisconsin, Illinois and Michigan.
Flood Potential Remains: Tropical Rain to Fuel Risk
Moisture-laden systems from the tropics, combined with slow-moving fronts, may cause flooding from the central Gulf Coast into the Appalachians and parts of the Midwest. This includes some areas devastated by deadly flooding during the summer.
Flash flooding will remain a concern early in the season across the Southwest due to the annual monsoon before it eventually dries out. Meanwhile, the onset of the wet season could cause localized flooding in the Pacific Northwest, where rain can quickly run off the parched soils across the region.
Fall allergies: “Allergies from grass and weed pollen will run higher than average into early fall from the Plains to the mid-Atlantic and Northeast where rainfall has been frequent and heavy throughout the late spring and summer,” AccuWeather Senior Meteorologist Alan Reppert said.
Severe Weather: Fall Storms Continue to Rattle the Central US
The collision of lingering summer warmth and encroaching cold air will trigger severe weather from the central Gulf Coast to the Ohio Valley. These regions are expected to see a moderate risk for damaging storms and tornadoes, especially in October and November.
Florida and the Southeast may also experience tornadoes tied to tropical systems in September and October.
Resurgence of storms: Fall is the second severe weather season, only behind spring, when powerful thunderstorms and tornadoes are most frequent across the country.
Fire Danger and Drought Still Fuel the Western Wildfire Risk
The wildfire threat will be elevated across the West through the first half of autumn, particularly in California, the Rockies and Northwest. Wind events may spark large fires in Central and Southern California as early as September, while lightning from moisture-starved thunderstorms could ignite fires farther north.
Fallout from Helene: “Dry fuels from Hurricane Helene in 2024 continue to be a high risk in western North Carolina, northwestern South Carolina and northern Georgia,” AccuWeather Lead Long-Range Expert Paul Pastelok explained.
Here’s how drought conditions will change throughout the season:
•Drought could worsen in the Northwest and Rockies before improving later in the season
•The monsoon could eliminate the short-term drought concerns in parts of New Mexico and Arizona, while dry conditions persist elsewhere in the Southwest
•Dry spells could lead to drought development in parts of the Great Lakes, Northeast and mid-Atlantic—similar to last year, though not as extreme.
First snowflakes – When Will You Need to Get Your Snow Shovels Ready
Snow may arrive early in the Rockies, downwind of the Great Lakes, and the coldest spots in the Plains, which are typical spots for early-season wintry weather. Snow lovers across the rest of the country may have to wait a bit longer than usual to see some snowflakes.
Lake-effect snow: It will be a slow start to the lake-effect snow season in the Great Lakes, but some areas could receive measurable snow in November.
Tropical threats – Fast-Developing Storm Potential Throughout Autumn
Warm waters will fuel the potential for particularly dangerous storms and hurricanes from late summer throughout autumn.
“Development can be quick, as they tend to form near land over the Southwest Atlantic, Gulf and Caribbean, giving short time to prepare, rather than farther out over the Atlantic,” AccuWeather Lead Hurricane Expert Alex DaSilva said.
Atlantic Hurricane season breakdown: AccuWeather is predicting an active Atlantic hurricane season, with 13 to 18 named storms, seven to 10 hurricanes, three to five major hurricanes and three to six direct impacts to the U.S. This includes Chantal, which made landfall in South Carolina as a tropical storm on July 6.
The Fall Forecast At-a-Glance
•Where will there be a warm start to fall? Across the Northeast, mid-Atlantic, Southwest and most of the Rocky Mountains.
•Coldest areas with chance of early snow: Great Lakes, part of the Plains.
•Flood-prone regions: Appalachians, Ohio Valley and central Gulf Coast.
•Wildfire hotspots: California, Northwest, Midwest, and areas of the Carolinas hit hard by Hurricane Helene in 2024.
•Severe weather zones: Central Gulf Coast to the Ohio Valley.
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