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Widespread heat has shattered records from coast to coast throughout the first half of summer, but the longest days of 2023 are in the rearview mirror and cooler weather is on the horizon.
Astronomical autumn officially arrives on Saturday, Sept. 23, at 2:50 a.m. EDT, a few weeks after the arrival of meteorological fall. Regardless of which date you celebrate the start of autumn, it may take some time before fall weather takes hold across the country.
AccuWeather’s team of long-range forecasters, led by veteran meteorologist Paul Pastelok, has analyzed weather patterns around the globe to piece together the weather forecast for the United States this fall.
One of the driving factors behind the weather patterns across the U.S. this autumn will be El Niño, a regular climate pattern that can reshape the jet stream. El Niño developed early this year when the water near the equator in the eastern Pacific Ocean warmed to at least 0.9 F above the historical average. The pattern replaced its cooler counterpart, La Niña, which persisted for three consecutive years.
Other factors have weighed on the minds of forecasters, including sea surface temperatures in the Atlantic and what has transpired in previous years when conditions were similar.
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Meteorological fall kicks off on Sept. 1, but summery weather will linger into the start of the new season for millions of people across the Northeast and Midwest.
The first frost of the season will hold off until October for the Northeast, and perhaps even early November for areas closer to the coast, which is more than a week later than the historical average. This could extend the growing season for farmers and gardeners across the region.
The arrival of cooler air across the Midwest and Northeast will also open the door for snowflakes to fall for the first time in months.
The snow will likely be limited to just flurries before the potential of widespread accumulating snow forces folks to dig snow shovels out from storage.
It has been a hot summer across most of the western U.S., and that theme will continue right into the start of autumn.
While the wet pattern will not be persistent across the Pacific Northwest throughout the entirety of autumn, an early rainstorm or two could help curtail the wildfire season across the region.
The U.S. wildfire season had a slow start in part thanks to a prolific winter season that saw many moisture-laded storms slam the West with historic snowfall amounts and drenching rainfall. However, this slow start to the fire season may not last.
The highest fire risk this year is expected in Northern California, eastern Oregon, eastern Washington, Idaho, and parts of Nevada.
Pastelok said a few fires could flare up in October as winds fan the flames, causing fires in California to grow.
Produced in association with AccuWeather