While vacationers in the United States avoided major severe weather ahead of Thanksgiving, they may not be so lucky for their post-holiday travels.
A new storm that first impacted the Pacific Northwest on Thanksgiving night is expected to develop into a full-fledged cross-country storm that could bring heavy rain and snow to more than 1,000 miles of the country this weekend.
The storm will also open the door to a new wave of frigid, frigid air, causing temperatures to plummet for millions of people just before the calendar turns to December.
Ahead of this, a strong and fast-moving winter storm is already causing problems for some travelers. Inches of snow and strong winds have already battered parts of the Midwest, with blizzard warnings in place for parts of Wisconsin and Michigan on Wednesday as the storm heads through the Great Lakes and toward Canada overnight.
The storm will be followed by significant lake effect snow for the rest of the week. A lake effect snow warning for up to 20 inches of snow and wind gusts of 50 mph is in effect from northeastern Ohio to northwestern Pennsylvania and southwestern New York.
Here’s what to expect from the storm after Turkey Day.
The storm will move into the Pacific Northwest on Thanksgiving night, bringing heavy rain and some high-elevation snow to the region.
As cold air begins to penetrate the northern United States, it will slide into the Rocky Mountains on Friday. Snow will begin to fall in parts of the northern Rockies and northern Plains as the storm mixes with wintry air.
The center of the storm is expected to move into the Plains region by Saturday morning and strengthen throughout the day toward the Midwest.
The line between rain and snow on Saturday will be quite clear, with precipitation spread across much of the central part of the country. There will be rain south of the center and snow in parts of Nebraska, Kansas and the Midwest. As the storm strengthens, so will the winds.
Areas east of the Mississippi River will have to deal with the storm Sunday, while the central part of the country will experience frigid, midwinter-like air. Snow is likely in parts of the Great Lakes and northern Appalachians, and continued rain is possible in the South.
The storm will move off the East Coast early Monday morning.
Although it’s difficult to determine the exact amount of snowfall in the days before the storm, it’s increasingly likely that snow will end November with a band stretching from the Rocky Mountains to the Appalachians.
Currently, the two most commonly used weather forecasting models (GFS and ECMWF) predict snowfall amounts in similar regions, but with different snowfall amounts in some locations. This discrepancy has to do with how each model predicts both the strength of the storm and the amount of cold air available.
A more accurate snowfall total forecast could be known by Friday. In any case, September to November of this year is the most widespread period of snow accumulation in the meteorological fall.
The storm could bring snow Saturday to areas around the Great Lakes, including Chicago, which have already seen snow this season due to lake effect snow.
Other typically snowy regions have so far been in short supply. Minneapolis has averaged at least half a foot of snow so far, but just recorded its first measurable snowfall (at least 0.1 inch) on Tuesday night. It’s 3 weeks later than usual.
The rain may also disrupt vacation travel south of snowy areas. Concerns are growing that heavy rain and possibly several thunderstorms could cause flash flooding in parts of the south starting Saturday.
Flash flooding is possible Saturday in parts of eastern Texas, including Houston, southeastern Oklahoma, Arkansas and Louisiana.
Rain will continue to fall across large areas of the east on Sunday. This rain is unlikely to cause flash flooding issues, but could cause speed reductions for those driving in the area.
Cold air has already begun moving into the country ahead of Thanksgiving, and even colder air is set to hit this weekend.
Another significant drop in temperatures will begin in the Rocky Mountains and Plains regions on Saturday as arctic air rushes into the United States on the back of the storm. High temperatures can be in the teens to low 20s as far south as Kansas.
Temperatures will drop to frigid levels overnight and into early Sunday morning. Low temperatures will be in the single digits across much of the north-central United States, with temperatures as far as north Texas dipping below freezing.
High temperatures on Sunday will be 15 to 20 degrees below normal for much of the central United States. In some parts of the Midwest, highs will remain below freezing, potentially reaching 30 degrees colder than normal.
The cold air is expected to spread eastward, with nighttime lows expected to be at or below freezing in much of southern Florida. Parts of Montana, the Dakotas, and the upper Midwest could wake up to temperatures several degrees below freezing on Monday, December 1st.
December marks the beginning of meteorological winter, which is December to February. It will feel that way in the first week of the season.
The upcoming arctic outburst could be a harbinger of an even deeper cold snap in December due to the collapse of the polar vortex.
