A powerful storm that left over 700,000 customers across the Pacific Northwest without power and propelled several cities in the region to their wettest start to any year on record is gaining steam as it pushes eastward. Parts of at least a dozen states and nearly 30 million Americans are under a combination of wind and winter weather alerts.
The bull's-eye stretches from the Northern Plains through the Upper Midwest as the difference in air pressure between a strong high-pressure zone currently in the Southwest and the incoming low from the Northwest generate powerful winds across the region.
On Wednesday, parts of Eastern Montana and the Dakotas reported near hurricane-force winds and springlike warmth as temperatures soared 20-25 degrees above average.
"It has been exceptionally mild for what is typically the coldest time of the year," according to CNN Meteorologist Taylor Ward. "Much of the region was in the upper 40s or 50s on Wednesday with a few locations even reaching the low 60s. The strong winds will usher in more seasonal conditions with temperatures generally in the 30s to low 40s on Thursday," Ward says.
As the storm surges toward the Midwest on Thursday, cold air behind the system is greeted by enough moisture to unleash persistent snowfall, gusty winds and periods of blizzard-like conditions in parts of Minnesota, Iowa, Wisconsin and the Eastern Dakotas.
The system is in no rush to move through the region however, as the impacts could linger well into Friday for millions across the Great Lakes. This prolonged snowfall, accompanied by periods of heavy lake effect snow on the south shores of Lake Superior will lead to widespread coverage of 3-6" of snow in the Upper Midwest with the highest totals likely ranging between 6-10" across Minnesota and northern Wisconsin.
As the system advances eastward Thursday night into Friday, periods of snow, rain and a wintry mix will impact parts Illinois, Indiana, Michigan and Ohio.
Rain and snow reach the Northeast Friday night
A secondary low pressure will form along the cold front as the system reaches the East Coast Friday night into Saturday morning.
While the storm promises to bring a soggy start to the weekend for the Northeast, the majority of the area will see rain, not snow, thanks to relatively mild January temperatures.
Places like New York City and Boston will be in the mid- to upper 40s Saturday with a half inch to an inch of rain as opposed to the several inches of snow they would see if temperatures were colder.
Snowfall Friday night and Saturday will be limited to Upstate New York and northern New England. For the most part, even those locations are only expected to see about two to five inches, though a few of the favored, higher elevation spots could see over a half a foot of snow.