A sudden drop in temperatures is forecast for four states in the central US, prompting meteorologists to issue a slew of freeze warnings on Monday.

National Weather Service (NWS) meteorologists issued freeze warnings for seven states on Monday, with some of those states expecting temperatures as high as 90 degrees overnight.

Missouri, Nebraska, Kansas and South Dakota are the states projecting the most severe temperature drops. During the day Monday, temperatures in each of these regions were in the high 50s and low 60s, with the forecast expecting temperatures to drop into the low 20s at night. Most freeze warnings were expected to come into effect overnight.

NWS meteorologist Michael Connelly explained Newsweek that it is “very common” in the Aberdeen, South Dakota area for temperatures to drop this low this time of year.

“We are very close to what the normal end of the growing season would be,” he said.

Temperatures are expected to rise again in some of the affected areas on Wednesday.

“Fall is a season of ups and downs! Expect another hard freeze tonight, with a cool start to the week before temperatures return to above normal,” the NWS office in Aberdeen, South Dakota, wrote on X, formerly Twitter. “With strong southerly winds, these warmer temperatures bring a greater fire risk.”

Minnesota, North Dakota and Michigan also had freeze warnings. The temperature was expected to drop by 20 to 25 degrees overnight.

“Frost and freezing conditions can kill crops and other sensitive vegetation and potentially damage unprotected outdoor pipes,” the NWS freeze warning said. “Take steps now to protect vulnerable plants from the cold. To prevent water pipes from freezing: wrap them or allow them to drain or drip slowly.”

In addition to freeze warnings, NWS meteorologists have issued several other cold weather-related advisories.

A freeze watch has been issued by NWS offices in Illinois, Maryland, Wisconsin, Pennsylvania, Nebraska, Iowa, Kansas and Missouri. NWS offices in Pennsylvania, Arkansas, Missouri, South Carolina, Maryland, Wisconsin, Iowa and Illinois also issued a freeze advisory.

Ice forms when the temperature is so low that the dew can freeze into ice. The temperature should be 32 degrees or lower, but frost can still crystallize even if the outside temperature is above freezing because the temperature near the ground can be as much as 10 degrees colder.

The cold temperatures come as AccuWeather released its 2024-2025 winter forecast for the United States. Much of the US, including the central, southern and eastern regions, is expecting temperatures slightly above normal during the winter.

Below normal temperatures are forecast for the Northwest, including Oregon, Washington, Idaho, Montana and Wyoming. This winter is also expected to bring several atmospheric rivers to the West Coast, namely California.