Rain and snow fronts are expected before and during Thanksgiving week, forecasters say

Several weather fronts will push rain and snow into the Midwest, Southeast, Mid-Atlantic and Northeast ahead of Thanksgiving week and some of the busiest travel days of the year.

By late Sunday, more than 25 million people were covered by National Weather Service watches and warnings related to winter storm activity, including those covering wind, flooding and freezing conditions.

Rain and thunderstorms were forecast for parts of the central and southern Plains on Monday, and a flood watch covered 4 million people from northwest Texas through central Oklahoma, federal and NBC News forecasters said.

Severe weather for West Texas, including Abilene, Wichita Falls and Midland, would likely bring 60 mph winds, thunderstorms and even a possible tornado, NBC News forecasters said.

The unsettled weather was expected to eventually affect 7 million people in the Dallas-Fort Worth region, NBC News meteorologists said.

Rain, snow expected this week

Starting in the Pacific Northwest, a “long-lasting atmospheric river” was expected to bring 5 inches of rain and at least 3 inches of snow to Oregon and northern California starting as early as Monday, federal forecasters and academic researchers said.

The Center for Western Weather and Water Extremes in San Diego developed an AR1 to AR5 system to predict the strength of atmospheric rivers similar to one used for hurricanes. On Friday, it said the incoming atmospheric river – with impacts likely Tuesday into Friday – would likely arrive as an AR3 or AR4 level phenomenon, indicating heavy to extreme rainfall.

The National Weather Service’s Weather Prediction Center said the stream of precipitation above would bring a chance of snow to parts of Colorado, Kansas, Nebraska, South Dakota and Wyoming after it leaves the Pacific Northwest.

Waves of low pressure were expected to follow and spread out into the Midwest, Southeast and Northeast after the first atmospheric river pulls in colder air and produces some snow into the weekend leading up to Thanksgiving week, they said.

An upper-level low-pressure system was forecast to develop over the Great Lakes and Northeast during the latter half of this week, the National Weather Service’s Weather Prediction Center said.

The system would pull temperatures down and block any potential warm fronts, it said.

“This will result in cooler temperatures, a cold rain from the Ohio Valley to the East Coast, and early season accumulation of snow for the central Appalachians and the higher terrain of the Interior Northeast,” the center said in its latest forecast.

Cooler, wetter fronts were expected to affect the East Coast in the second half of this week, with rain and some snow accumulation expected in the Great Lakes, Ohio Valley and Northeast.

Federal forecasters said a surface cyclogenesis — a possibly major winter storm — could develop and spin across the Mid-Atlantic and southern New England regions, bringing temperatures down 10 degrees and producing rain and some snow accumulation Wednesday and Thursday.

Snow may be limited to the Northeast Interior regions and mountain ranges, federal forecasters said, but it would come in the middle drought and even forest fires that has so far characterized the decline in places like New York, New Jersey and Pennsylvania.

Forecasters said as much as 6 inches of snow was possible.

“Cold air aloft will be sufficient to support early-season snow accumulation for the higher terrain near the Great Lakes and interior Northeast, and especially for the central Appalachians,” the Weather Prediction Center said in its forecast Sunday.

Looking forward to Thanksgiving

Federal forecasters often avoid making predictions beyond seven days, but were confident that cooler temperatures, cold rain and high elevations would arrive on the East Coast on Sunday of the week that marks the Thanksgiving holiday, Black Friday shopping and one of the ​​the busiest periods of the year for travel.

Nearly 80 million people are expected to travel more than 50 miles during the holiday season AAA said Mondaywith unprecedented numbers set to drive and fly to see friends and family.

The US Climate Prediction Center’s six- to 10-day forecast, which extends into the first half of the holiday week, said California, the Pacific Northwest, Montana, North Dakota, South Dakota, Nebraska, Iowa, Minnesota and some states on the Great Lakes. , such as Wisconsin and Michigan, “leaned” in favor of above-average rain.

The forecast calls for more rain in the San Francisco Bay Area. The rest of the country is likely to receive normal or below-normal rainfall during that time, the prediction center said.

There are indications that Thanksgiving week will continue a post-pandemic trend of increased holiday travel. American Airlines said in a statement Thursday that it expects to set a record for passengers served during the holiday period, with nearly 8.3 million expected.

The last high mark for travelers with American came last year, when it estimated that nearly 6.5 million people flew on its and subsidiary planes.

Likewise, the National Retail Foundation said Thursday that it expects a record number of shoppers expected to set foot in brick-and-mortar retailers during the holiday week: 183 million.

It may be too early to tell whether brewing rain and snow systems will thwart travel and spending plans.

This article was originally published on NBCNews.com