This week, the changing seasons will be evident across the U.S. with a combination of serious storms, winter weather, and dramatic temperature fluctuations, leading to a busy weather week for millions of Americans.

The National Weather Service predicts widespread rainfall and significant snowfall in mountainous areas in the Northwest and northern Rockies on Monday. Locations at higher elevations in the Cascades and northern Rockies could see up to a foot of snow, complicating travel plans for drivers.

Central parts of the U.S. could experience thunderstorms along a cold front, with the possibility of strong winds and even tornadoes in central Oklahoma and North Texas on Monday afternoon and evening.

In the latter part of this week, a blast of cold air is expected to sweep across large sections of the central, southern, and eastern U.S. Meteorologist Jonathan Erdman from Weather.com stated, “This colder air should reach the Plains around Wednesday, then quickly spread over the South, lower Midwest, and East by Thursday,” adding, “It may linger into the weekend.”

Precipitation Affects the West; Freeze Alert in California

In much of the Northwest, Northern Great Basin, and northern Rockies, a cold front sweeping through on Monday will lead to unpredictable weather ahead of another significant storm system expected to develop off the Northwest coast on Tuesday, according to the weather service.

“This initial round of precipitation at the start of the workweek will likely include moderate to heavy snowfall in the Cascades and northern Rockies,” said meteorologist Cody Snell.

Due to the snowfall, the weather service cautions that roads, particularly bridges and overpasses, may become slippery and hazardous throughout Monday and into Tuesday. They advise, “Plan for slick roads. If travel is necessary, carry extra supplies like a flashlight, food, and water in case of emergencies.”

In California, a hard freeze is expected in much of the central valley on Monday night, with forecasters warning that “Frost and freeze conditions could harm crops and sensitive plants, as well as possibly damage any unprotected outdoor plumbing,” according to the weather service in Sacramento.

Central U.S. Faces Tornadoes and Heavy Rain

Monday afternoon and evening may see the risk of tornadoes and damaging winds stretching from parts of east Texas into Louisiana, as noted by the Storm Prediction Center.

A tornado watch is anticipated to be issued later on Monday for Texas and Louisiana, indicating favorable conditions for tornado formation.

Additionally, heavy rainfall is expected Monday night in eastern Louisiana and southern Mississippi, with the threat of rain moving east to the Florida Panhandle on Tuesday, according to the weather service.

Winter’s Approach; End of Hurricane Season Nears

A significant storm is developing midweek around the Great Lakes, which could bring winter-like changes to much of the eastern U.S. and provide much-needed rain, as per AccuWeather meteorologists.

As for the expected cold temperatures later in the week, Erdman noted that lows in the 30s and 40s will be common in the South, and even Florida may experience cooler mornings in the 40s and 50s. Meanwhile, Midwest and interior Northeast residents can expect daytime highs in the 40s, with some areas even dipping into the 30s.

With the arrival of this colder air, there’s good news regarding tropical weather: “This major storm in the Midwest, along with the colder air spreading into the South and East later this week, will effectively eliminate the risk of any tropical storms making landfall in the U.S.,” stated Brett Anderson, a senior meteorologist with AccuWeather. “Some tropical activity may linger over parts of the Atlantic basin, but it would be deep in the tropics or over the central Atlantic, far from the U.S.”

The former tropical storm, Sara, dissipated over the Yucatan Peninsula on Monday morning. Hurricane season officially concludes on November 30.