Freeze warnings issued for millions with the coldest temperatures in months incoming

A dramatic pattern shift is bringing the chilliest air since spring to millions of people in the central and eastern United States, making areas that have struggled so far to shed lingering warmth feel more like November than October.

Extended periods of fall chill have been hard to come by for much of the country since the season began last month. But the combination of an expansive cold front and an upcoming surge of cold, Canadian air, will change that and temperatures could drop to 10 to 15 degrees below average by midweek.

As of Tuesday morning, more than 60 million people from the Plains to the Appalachians and Northeast are under some sort of frost or freeze alert as temperatures drop.

The first aspect of this cooldown — a far-reaching cold front — began over the weekend. This cold front swept from the north-central US through the eastern half of the US Monday, ushering in a true autumn chill for some along the way. Even chillier air from Canada will get pushed much farther south throughout Tuesday and Wednesday.

Tuesday could be the coldest day of the week in Chicago, where the high temperature could struggle to reach 50. Before Monday’s high of 57, Chicago hadn’t recorded a high in the 50s since April.

Temperatures will drop again on Wednesday for many areas outside the Midwest. Wednesday is likely to be the coolest day since spring for millions, and in many locations, it’ll feel more like late November than October.

“Truly fall-like weather is forecast … through the start of the weekend” farther south, the National Weather Service in Atlanta said Monday.

The high temperature in Washington, DC, on Wednesday could top out in the mid-50s — 10 to 15 degrees lower than normal for mid-October.

Atlanta could struggle to break into the low 60s on Wednesday and remain in the 60s through Friday. The city hasn’t had a high temperature reading below 70 degrees since May and typically tops out around 75 degrees this time of year.

Wednesday will also be the chilliest day of the week for large portions of the Northeast, with highs in the 40s and 50s for many. With daytime temperatures this chilly, it leaves room for overnight temperatures to possibly dip below freezing. Given the chill, a few snow flurries could dust the highest elevations of West Virginia to New York and New England Tuesday night.

“Frost and freeze conditions are probable for several nights and in many areas this week,” the National Weather Service in State College, Pennsylvania, warned Monday.

Frost and freeze alerts are active for millions this week and more could be issued in the coming days.

Freezing conditions can kill plants that are left unprotected from the cold or end the growing season for some regional staples. These conditions are also dangerous for anyone without access to adequate heating.

Freezing or-near freezing low temperatures are possible each night from Tuesday through Thursday in western North Carolina, which was devastated by Helene late last month.

Temperatures will ease back to more typical October conditions late this week in much of the central US and Northeast. The chill will linger through at least Friday for areas farther south like the southern Appalachians and the Southeast.

By Saturday, more seasonable highs in the 70s and 80s will return for the Southeast while 60s and 70s will be common north into the Midwest and parts of the Northeast.

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