A freeze warning is in effect in parts of Oregon as temperatures could drop to -1°C.

The notice applies to the cities of Enterprise, Joseph and Wallowa in Wallowa County, in the northeastern part of the state, on Wednesday morning — from 11 p.m. PDT on Tuesday until 9 a.m. PDT the following day.

The National Weather Service (NWS) reported: “Freeze and freezing temperatures can kill crops and other sensitive vegetation and potentially damage unprotected outdoor utilities.” People were warned to “take steps to protect vulnerable plants from the cold.”

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According to the NWS Pendleton, there is a 75 percent chance the Enterprise will encounter freezing temperatures, 60 percent in Joseph, 40 percent in Lostine and 20 percent in Wallowa.

The NWS made the announcement during a public meeting on Wednesday, as the first snowflakes of the season are expected in higher elevations in northwestern Montana.

This is caused by “significantly colder air” behind the “strong cold front associated with the next low pressure area moving across the northern Rocky Mountains.”

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Meanwhile, “record heat” is expected in the mid-Atlantic for the day, and the Ohio and Tennessee Valleys will see the heat last “a few more days.”

The NWS reported: “A cold front has brought some relief from the heat across the northern Plains and also brought severe thunderstorms to the Midwest this morning.

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“As the front moves further east and southeast, the Mid-Atlantic states are expected to experience a day of record heat, with temperatures around the nation’s capital reaching 100 degrees Fahrenheit.”

Extreme heat warnings were issued for parts of the Midwest on Tuesday, with temperatures expected to rise above 90 degrees Fahrenheit.

In recent days, parts of the US have been hit by extreme weather, ranging from heat waves to blizzards and flash floods.

While millions of people in the Midwest were battling an extreme heat wave, an unusually cold storm swept across the Gulf of Alaska, bringing a taste of winter to the West Coast.

Meanwhile, three tropical cyclones hit the Pacific Ocean on Monday. They were Tropical Storm Hone, which brought heavy rains to Hawaii, Hurricane Gilma and Storm Hector.

Arizona hiker Chenoa Nickerson died in a flash flood at the Grand Canyon, swept away into the Colorado River before her body was tragically found on Sunday.

The flooding left several hikers trapped, but more than 100 people were evacuated by UH-60 Blackhawk helicopters after Arizona Governor Katie Hobbs activated the state National Guard.