Will Illinois see a ‘frosty, wet’ fall? Farmers’ Almanac, forecasters expectations differ

Autumn will officially begin in the metro-east in less than six weeks, and meteorologists forecast a potentially warm season.

The popular Farmers’ Almanac has a contrasting prediction, though.

Residents of southwestern Illinois and St. Louis have about a 33% to 40% chance of above-normal temperatures from August to October , the National Weather Service reports, and about equal chances of above- or below-normal precipitation.

This week is looking rainy in Belleville, and the NWS St. Louis office forecasts thunderstorms Wednesday night to Friday.

Daylight has begun to dwindle in Illinois after the summer solstice passed in June, but daylight saving time is in effect until Nov. 3. Fall officially begins Sept. 22.

Here’s what to know about fall weather, including a prediction from the Farmers’ Almanac and scientific data from meteorologists with the NWS.

What is typical fall weather for Belleville, Illinois?

The NWS St. Louis office provides monthly climate data from 1991 to 2020. Here’s what to know about average fall weather in Belleville and St. Louis.

August:

• Average minimum temperature: 65.3 degrees Fahrenheit

• Average maximum temperature: 89.1 degrees

• Average overall temperature: 77.2 degrees

• Total normal precipitation: 3.92 inches

September:

• Average minimum temperature: 56.9 degrees

• Average maximum temperature: 83.3 degrees

• Average overall temperature: 70.1 degrees

• Total normal precipitation: 3.35 inches

October:

• Average minimum temperature: 46.7 degrees

• Average maximum temperature: 72.6 degrees

• Average overall temperature: 59.7 degrees

• Total normal precipitation: 3.12 inches

November:

• Average minimum temperature: 36.9 degrees

• Average maximum temperature: 58.1 degrees

• Average overall temperature: 47.5 degrees

• Total normal precipitation: 3.6 inches

Farmers’ Almanac fall predictions for the Midwest

The almanac predicts a “cool, crisp” fall across the U.S. this year.

The Farmers’ Almanac’s 2024 Autumn Outlook foresees “frosty, wet” conditions in Illinois and “frigid, wet” conditions in Missouri and surrounding states.

Midwest residents can expect dry weather in time for Halloween, the almanac says.

The organization makes predictions based on a mysterious formula that considers factors such as planetary positioning, sunspot activity and tidal action of the moon.

“The only person who knows the exact formula is the Farmers’ Almanac weather prognosticator who goes by the pseudonym of Caleb Weatherbee,” the organization’s website says. “To protect this proprietary formula, the editors of the Farmers’ Almanac prefer to keep both Caleb’s true identity and the formula a closely guarded brand secret.”

The Farmers’ Almanac has provided extended forecasts since 1818, according to its website.

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