Arctic blast cripples post-Thanksgiving travel as thundersnow and blizzard conditions threaten millions

An Arctic blast gripped the northern Plains, Midwest and Great Lakes on Saturday, with millions of Americans under freeze warnings.

More than 17 million people were cautioned Saturday under National Weather Service winter alerts, including 3.6 million under lake-effect snow warnings, 4.5 million under freeze warnings, 8.5 million under winter weather advisories, and 1 million under frost advisories.

Affected areas included the Great Lakes and the Central Plains to the Appalachians, with many of those freeze warnings focused on the Southeast.

The National Weather Service warned that the Arctic airmass is delivering the coldest temperatures since last winter. Wind chills in the northern Plains and upper Midwest are expected to plunge below zero Saturday morning. Parts of North Dakota could experience wind chills as low as minus 30 to 40 degrees, according to the agency.

The icy airmass was also helping to produce serious and travel-thwarting lake-effect snow downwind of the Great Lakes in northeast Ohio, far northwest Pennsylvania, western New York, and portions of northwest New York, federal forecasters said.

The highest snow accumulations are expected east of Lake Ontario, where some isolated areas could be hit by up to 60 inches of lake-effect snow by early next week around the Watertown, New York, area, the NWS said.

The weather service says lake-effect snow is produced when a cold airmass moves south from Canada and beyond over the comparatively warm Great Lakes, pulling some of the lake water quickly into the atmosphere, forming fertile clouds and generating snow at a rate of 2 to 3 inches and more each hour.

Early Saturday evening, Watertown International Airport measured only fractions of an inch of precipitation for the day, with the weather service reporting 4 to 7 inches of snow depth for the entire city. More serious snow was still on tap, the weather service in Buffalo said.

“Chance of precipitation is 100%,” it said in an extended forecast for Watertown on Saturday. “Total nighttime snow accumulation of 15 to 21 inches possible.”

Wind gusts will likely cause blowing and drifting snow, as well as isolated power outages, and visibility will be drastically reduced with near whiteout conditions.

Governor Kathy Hochul on Saturday warned New Yorkers to avoid unnecessary travel. More than 100 National Guard troops were staged in Western New York “to support local communities,” Hochul said in a statement.

“Please heed travel advisories and look out for one another,” she said.

Interstate 90 in western New York reopened to passenger vehicles Saturday afternoon after it was closed in reaction to its snow-triggered closure in nearby Pennsylvania on Friday, Hochul announced.

Commercial trucks were still banned in both directions along the westernmost portion of the interstate starting at Exit 46, she said on social media platform X.

A day earlier, the governor declared a state of emergency for several counties, including Erie and Oswego. At times, snowfall rates will be blinding, at 3 to 4 inches an hour, and could be accompanied by thundersnow, a rare weather event that combines a snowstorm with thunder and lightning, creating hazardous travel conditions.

By Friday night, more than 20 inches of snow had already fallen along Lake Erie’s shores in parts of Ohio, Pennsylvania, and New York, according to the NWS. Video from Saturday morning showed roads in Ashtabula, Ohio, covered in snow, making it difficult for drivers to use them.

Erie, Pennsylvania, recorded 30 inches of snow, the highest total so far, according to the agency.

A power outage in Terminal D at the Philadelphia International Airport Friday night impacted nearly 40 flights, although none were cancelled. Power was restored to the terminal Saturday afternoon.

Also on Saturday, Pennsylvania Gov. Josh Shapiro signed a proclamation of disaster that his office said would help those affected by the lake-effect snow quickly tap response and recovery funds, according to a statement.

He said more than a dozen Pennsylvania National Guard members were assigned to assist the Erie County Emergency Operations Center with rescuing stranded motorists and moving abandoned, crashed or otherwise incapacitated vehicles. 

The weather service office in Cleveland said on Saturday that more than a foot of lake-effect snow was possible in parts of the region starting at noon Sunday and continuing through 7 a.m. Tuesday.

Additional travel disruptions have choked post-Thanksgiving travel plans, especially along Interstate 90 between Cleveland and Buffalo. Social media videos taken on Friday showed drivers stuck in bumper-to-bumper traffic in a snowstorm on the interstate.

Storm totals up to 3 to 6 feet will be possible through Monday, continuing to impact travel between Cleveland and Buffalo.

Buffalo Mayor Christopher P. Scanlon said the city was ready for the snow.

“I can tell you that the city of Buffalo is prepared for the weather that’s moving in, not just today, but for days and weeks leading up to this,” he said at a news conference Saturday.

The city opened three warming centers, available 24 hours a day for the time being, for those who may need warmth and shelter, he said.

The National Weather Service said that travel “could be very difficult to impossible” in spots downwind of the Great Lakes.