Polar Vortex to Plunge Millions in America into Arctic Freeze

Millions of Americans are bracing for an Arctic freeze as extreme weather conditions approach the holiday season. The U.S. National Oceanic and Atmospheric Administration’s Weather Prediction Center has issued numerous alerts across states including Oregon, Washington, Idaho, Montana, Michigan, Washington D.C., Pennsylvania, and New York.

Forecast Overview

Forecasters predict frigid temperatures well below the seasonal average, particularly in the Midwest and East Coast. A winter storm warning currently affects south-central Virginia, including the Richmond area, forecasting 3 to 5 inches of snowfall. In adjacent regions of the Appalachians and southern Mid-Atlantic, 1 to 2 inches of snow are expected.

Impact of the Polar Vortex

The impending cold wave is attributed to a disruption of the polar vortex, a low-pressure system that can expand into the Northern Hemisphere during winter. This breakdown leads to sudden stratospheric warming, which compromises cold winds and alters the jet stream, pushing Arctic air southward.

Paul Pastelok, Lead Long-Range Meteorologist at AccuWeather, noted that the polar vortex has been weakened since late November. The result has been a marked push of Arctic air across the central and eastern U.S., which may continue for the next couple of weeks.

Temperature Projections

Temperatures are expected to plunge below zero Fahrenheit early next week, averaging 15 to 25 degrees below normal. Pastelok predicts two to three additional rounds of cold weather between December 10 and 19, with a potential frost or freeze affecting parts of central Florida later next week.

Precipitation and Flooding Risks

• Forecast anticipates over a foot of snow in high-elevation areas of the Cascade and Northern Rocky Mountains.
• The Pacific Northwest is likely to receive 6 to 12 inches of rainfall over the coming days.
• Urban flooding and riverine flooding are risks due to a prolonged atmospheric river carrying substantial moisture from the tropics.

Coastal regions may see rainfall accumulation of 4 to 6 inches, while mountainous areas could experience up to 8 to 12 inches of precipitation, mixing rain with snow at higher elevations. The Weather Prediction Center emphasizes that flash flooding might occur due to escalating rainfall and runoff.

Severe Weather Outlook

As the atmospheric river moves inland, increased rainfall and potential flooding are anticipated across coastal Washington and Oregon. The weather system could lead to scattered instances of wintry conditions and gusty winds across the Northern Plains and Upper Midwest.

With this extreme weather ahead, residents in impacted areas should prepare for snow, rain, and significant temperature drops as the Arctic plunge begins.