A sure sign of the changing season is appearing on weather maps across the northern U.S. this week: Frost and freeze alerts, which signify the end of the growing season for millions of farmers and gardeners.
As of the morning of Oct. 7, frost advisories and freeze warnings stretched all the way from Idaho to Michigan.
“Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing,” the National Weather Service in Duluth, Minnesota, warned.
“Sensitive outdoor plants may be killed if left uncovered,” the weather service in Grand Forks, North Dakota, said.
More frost and freeze alerts were likely to be posted over the next few days across interior portions of the eastern U.S., the weather service predicted.
What is a frost advisory? A freeze warning?
According to the weather service, a frost advisory warns that temperatures might drop to near or slightly above freezing (33 to 36 degrees). Temperatures that low could lead to widespread frost, potentially damaging sensitive plants.
A freeze warning indicates a more significant drop to 32 degrees or lower, signaling the end of the growing season and increased plant damage. (Further, a hard freeze, which often comes with a hard freeze warning, involves temperatures below 28 degrees for several hours, causing severe damage to most plants.)
Frost and freeze warnings were in effect across the north-central U.S. on Oct. 7, 2025.
Cold weather heading east
The threat of cold weather will extend further to the east over the next few nights.
In New York State, the weather service in Binghamton said “a much colder high pressure system will drop south over the region Wednesday (Oct. 8) and last into Friday (Oct. 10). The potential exists for widespread frost and freeze conditions Thursday morning (Oct. 9) and especially Friday morning. Minimum temperatures both mornings could be close to or below freezing. Friday morning could have many locations minimum temperatures in the upper 20s to low 30s.”
In Virginia, a few locations in the Alleghenies, Potomac Highlands and Central Shenandoah Valley may cool into the mid- to upper-30s, the National Weather Service in Washington, D.C., said. “Patchy frost may be possible in those locations late Wednesday (Oct. 8) night.”
In Maine, “Temperatures will drop below freezing over the entire area Thursday (Oct. 9) night, leading to widespread frost. Frost and freeze conditions could kill sensitive vegetation.”
Also in Maine, an early warning about wind chill appeared in the forecast for the first time this season: “Windchills will be about 10 degrees lower, though, than air temperatures.”
What about snow?
Although there was some snow in the forecast over the northern Rockies this past weekend, most of the United States looks to be snow-free over the next few days, according to the weather service.
This article originally appeared on USA TODAY: Frost, freeze alerts on the way as growing season comes to an end
