Meteorologists blame a stretched polar vortex, moisture, lack of sea ice for dangerous winter blast

By SETH BORENSTEIN, AP Science Writer

WASHINGTON (AP) — Warm Arctic waters and cold continental land are combining to stretch the dreaded polar vortex in a way that will send much of the United States a devastating dose of winter weather later this week with swaths of painful subzero temperatures, heavy snow and powerline-toppling ice.

Meteorologists said the eastern two-thirds of the nation is threatened with a winter storm that could rival the damage of a major hurricane and has some origins in an Arctic that is warming from climate change. They warn that the frigid weather is likely to stick around through the rest of January and into early February, meaning the snow and ice that accumulates will take a long time to melt.

Forecasts have the storm, expected to hit starting Friday, stretching from New Mexico to New England and across the Deep South. About 230 million people face temperatures of 20 degrees (-7 degrees Celsius) or colder and around 150 million are likely to be hit by snow and ice, with many Americans getting both, according to the National Weather Service.

“I think people are underestimating just how bad it’s going to be,” said former National Oceanic and Atmospheric Administration chief scientist Ryan Maue, now a private meteorologist.

The pola...