U.S. faces first major Arctic outbreak of winter, dangerously cold wind chills expected

The United States is bracing for its first significant Arctic air outbreak of the winter, impacting the north-central region with bitterly cold wind chills and extending through the weekend. The northern Rockies and Plains are particularly at risk, with the Arctic surge also expected to bring record-breaking cold to the south-central U.S.

• The first significant Arctic outbreak of the winter will arrive in the northern Rockies and northern Plains Thursday night and Friday, January 11 and 12, 2024, before advancing farther south and east through much of the Plains and Midwest this weekend. Numerous daily cold records are likely in the south-central U.S. on Sunday, Monday, and Tuesday, January 14 – 16.
• At the peak of the Arctic outbreak early next week, minimum wind chills should fall below -18 °C (0 °F) into Texas and the interior Southeast.  Wind chills this weekend across the northern Plains and northern Rockies should be below -35 °C (-30 °F). This will pose an increased risk of frostbite on exposed skin and hypothermia. Have a cold survival kit if you must travel.
• Arctic air will gradually lower snow levels in time for the arrival of another storm system in the West on Friday. This may lead to snow and considerable impacts in valleys in Oregon, Idaho, Nevada, and Utah, including the Portland, Boise, and Salt Lake City metro areas. Freezing rain is likely on Saturday in western Oregon. 
• Snow is likely on the periphery of the advancing Arctic air mass from the interior South into the Mid-Atlantic Sunday into Monday and possibly over the Northeast into midweek.

The onset of this winter’s first major Arctic air outbreak is currently underway in the north-central United States. According to the National Weather Service (NWS), this cold surge is forecast to spread south and east, impacting areas from the northern Rockies and Plains through the weekend.

The NWS warns of dangerously cold wind chills that could lead to increased risks of frostbite and hypothermia.

In today’s Short Range Forecast Discussion, NWS forecaster Putnam noted that an upper-level trough moving over the Southwest U.S. will contribute to the development of a significant surface low pressure system. This system is expected to track northeastward, bringing widespread showers and thunderstorms, particularly over eastern Oklahoma/Texas and into the Middle and Lower Mississippi Valley. The Storm Prediction Center has outlined an Enhanced Risk of severe weather for these areas, with potential flash flooding.

Heavier rainfall is anticipated to stretch northward into the Mid-Atlantic and southern New England, with urban areas at risk of flooding due to saturated ground conditions and elevated stream/river levels. Coastal flooding is also a concern from the Mid-Atlantic to New England.

Following the storms, a surge of Arctic air is set to descend into the heart of the country. Temperatures in the Northern Plains are expected to drop below -17.8 °C (0 °F), with record lows forecasted below -28.9 °C and -34.4 °C (-20s and -30s °F) for Saturday morning.

These conditions, coupled with gusty winds, will result in extremely cold wind chills, potentially as low as -37 to -46 °C (-35 to -50 °F) in parts of the Northern Plains and as low as -26 to -34 °C (-15 to -30 °F) in the Central Plains.

The Arctic air will also affect the Midwest and Southern Plains by Sunday, with upstream colder air over the West bringing heavy snow, particularly in the higher elevations of the Cascades and Wasatch. Lower elevation areas, including Portland, OR, and Boise, ID, are under Winter Storm Watches/Warnings, with several inches of snow expected.

References:

¹ Short Range Forecast Discussion – NWS Weather Prediction Center College Park MD – 311 PM EST Thu Jan 11 2024

Featured image: Temperature forecast for January 16, 2024. Credit: Ventusky, TW.