Winter storm, blizzards to disrupt holiday travel this week across U.S.


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A massive storm system is set to upset vacation travel and bring a bout of wintry weather to millions across the Plains, Great Lakes, Ohio Valley, Northeast and even the interior mid-Atlantic. The developing hurricane will bring heavy snowfalls and blizzards to some and heavy rain to others between Wednesday and Friday night, all at a time of year when more than 110 million Americans are expected to take to the roads and air.

The potential for serious travel disruptions exists at major airport hubs in the Midwest and Great Lakes, including Chicago’s O’Hare International Airport, where heavy snow and gusty winds are expected - with worst conditions Thursday through Friday.

The National Weather Service office serving Chicago wrote that travel “can become extremely dangerous and life-threatening, especially given the frigid temperatures during the height of the storm.”

4 things you need to do right now to prepare yourself and your home for the extreme cold

Nearly 50 million Americans are under winter storm warnings, watches, and warnings, and a number of them may find themselves surrounded by blizzard warnings before long. The forecast storm system will strengthen explosively, at a rate enough to qualify it as a “bomb hurricane” — the most intense strain of mid-latitude storms.

“In short, this still looks to develop as an evolving life-threatening event,” the Weather Service office serving Minneapolis wrote.

The Bureau of Weather Service serving Buffalo called it a “once in a generation” storm system.

Airports across the eastern United States could experience cascading delays thanks to strong winds surrounding the system, which will stretch for nearly 1,000 miles. This can lead to effects far and wide from Minneapolis and Milwaukee to Boston and Washington, D.C. Strong winds may result in power outages in locations that experience dangerously low temperatures.

The storm will drag a historically cold December air mass — sourced from Siberia — over much of the lower 48 between late Wednesday and late Friday, bringing temperatures about 30 to 50 degrees below average. Readings in the teens can stretch all the way to the Gulf of Mexico, with a serious flash freeze turning wet roads into a sheet of ice in some areas.

More than 30 million people are under wind chill alerts from the Rocky Mountains to the center of the country. Wind chills expected Friday morning include: 2 degrees in Houston; minus -7 in Dallas; minus 14 in Memphis; minus 32 in Kansas City, Missouri; and -45 in Sioux Falls, SD

“Very cold wind chills, as low as minus 50” are expected in the Dakota, the National Weather Service wrote. “Stranded motorists will risk frostbite, hypothermia and even life-threatening exposure.”

Freezing air will bleed all the way to the East Coast on Friday, setting the stage for the coldest Christmas since 1989 in many locations.

Possible severe blizzard in the central United States

Turbulence broke out Tuesday morning over British Columbia, Alberta and Saskatchewan. It will intensify and coalesce into a bowling ball-shaped area of ​​low pressure at high altitudes, which will plunge south over the Northern Plains, Corn Belt, and Missouri Valley between Wednesday night and Friday. This will help create a strong area of ​​low pressure near the ground that will quickly strengthen, becoming a “bomb tornado”.

The tornado will first form over the high plains of Colorado, Oklahoma and New Mexico on Wednesday night, and will head toward Memphis by noon Thursday before beginning rapid intensification. By Friday morning, it will be near the Ohio River in northern Kentucky. Then it will intensify greatly on its way to Canada across the Great Lakes.

On the storm’s west side, moisture that wraps around the depression and drops into the cold air will deposit a mass of thick snow, with total jackpots likely to exceed 12 inches. It’s not clear where the cap will fall, but it looks like Wisconsin and Michigan’s Upper Peninsula could be in the double digits for totals. It is likely 6 to 10 inches wide along the shores of Lake Michigan, including Chicago, with a spread of 3 to 6 across most of the rest of the Upper Midwest, Corn Belt, and Northeastern Plains.

Across most of the Great Lakes region, heavy snowfall and worst conditions are expected between late Thursday afternoon and Friday night. Conditions can gradually improve on Saturday, though winds may blow away the falling snow, reducing visibility.

Snow falls over the Central Plains Wednesday night through Thursday. As the system strengthens, snow will become thicker and more extensive Thursday afternoon, at which point it will snow moderately to heavily in Chicago and possibly all the way to Nashville.

Around this time, winds will pick up significantly, with widespread gust gusts of 35 to 50 mph. This will lead to a blizzard or near-blizzard in most of the north central United States and western Great Lakes as dangerously cold air flows into the area behind the storm’s cold front.

Even after the main slug passes early Friday, moisture swirling in the “clincher head” of the hurricane will keep light to moderate snow passing over Lake Michigan, especially the East Lake shore.

Snow will eventually shift into the Midwest and northern Ohio Valley before acting in the Northeast as rain initially, as temperatures there will be much warmer. However, in western Pennsylvania and New York, the rain must change to snow with a wind before it ends, causing hazardous conditions Friday night and Friday. Even locations farther east, toward the Interstate 95 corridor, could see a change in precipitation to a very brief period of snow as the Arctic front comes in during Friday. With the rapid drop in temperatures, this can lead to slick roads.

Although the storm will lift into Canada on Christmas Eve, strong winds around it will generate areas of heavy lake-effect snow on beaches downwind of the Great Lakes on Christmas Day - including around Buffalo

Inland wintry weather Mid-Atlantic Thursday

Outside of the main blizzard’s area of ​​influence, a second area related to wintry weather could emerge on Thursday. It will occur before a major low pressure system as moisture trickles over the Appalachian Mountains on Thursday. The frigid air trapped in the mountains will take some time to clear, so the initial precipitation will fall as snow and eventually freezing rain.

Winter storm watches are in effect for Allegheny in western Maryland, eastern West Virginia, and neighboring West Virginia. This is where 4 to 6 inches of snow is likely to be, along with up to a quarter inch of ice. This may affect travel on Interstates 68 and 81 Thursday morning during the day.

Why can flight delays abound?

The sheer size of this storm, which will stretch across more than 1,000 miles, is impressive in itself. Together with the powerful North Pole high pressure system to the west, however, the resulting asymmetry would be noteworthy. This extreme change in air pressure with distance will result in primarily strong winds over the eastern half of the Lower 48 Thursday through Friday. Gusts of 40 mph will be common, with some areas — especially near the Great Lakes — seeing gusts in excess of 50 mph. Tree damage and power outages are possible in areas where it is dangerously cold.

When strong winds intersect runways at perpendicular angles, flight delays will be frequent. For flights that take off, weather turbulence will make the flight uncomfortable. This is especially true late Thursday through Friday.

Meanwhile, already frigid temperatures are gathering over the northern plains, heralding a chilling air mass south over the United States in the next 24 to 48 hours. Temperatures can drop by as much as 40 degrees or more in spots, dropping to levels comparable to the 1989 cold air outbreak.

In the Texas Panhandle, this front would be a true Blue North. Readings from the mid-40s will drop into the single digits in the next 5 or 6 hours on Wednesday night.

Houston will move from the mid 60s into the upper 60s on Thursday afternoon into the lower 20s by Friday morning with a wind chill in the single digits.

Next, a flash-freeze front will reach the East Coast, with highs in the 40s and 50s on Friday, replaced by lows in the teens by nightfall. Some models even report a 30-degree drop in temperature at points in 3 hours, which would defy the record temperature fluctuations along the Interstate 95 lane. Any roads in wet areas can turn rain or change rain into snow to snow.

A major storm to soak up the metropolitan area ahead of the cold Christmas weekend

After it invades the coldest air, it should linger for 48 to 72 hours. Bitter cold will explode in Denver on Wednesday night, bringing temperatures down from 40 degrees to zero in a matter of hours. By Thursday morning, it will be near minus 10 with winds chilling around minus 30. St. Louis, which will see highs in the mid-30s on Thursday with some snow, will drop to -4 degrees below zero on Thursday evening. By Friday, highs will hover around 6, with lows around zero. Teens are likely to rise on Saturday.

Chicago will be in the single digits Thursday night through Saturday. Kansas City will drop to -8 minus Thursday night, and highs probably won’t make it much higher than 4 or 5 degrees on Friday.

Lows in the -20s and -30s will be common across the Dakota and Montana, and some places won’t make it above -10 degrees below zero for several days in a row. Wind chills range from -40 to -55 degrees.

Particularly impressive in this episode is how far south the cold air will blow. Practically everyone along the Gulf Coast from Galveston to Tampa will see it, including New Orleans, Gulfport, Mississippi. This will create “Arctic sea smoke” over the bay, or a rare type of mist that looks like steam that forms when cold air blows over warm waters.

Towards the east coast, temperatures will be 10 to 25 degrees Celsius lower than normal on Christmas Eve and Christmas Day. From Washington to Boston, highs should stay below freezing with lows in the teens.

Much of Florida, except for the southernmost portion, will drop into the 30s or lower Saturday night.