Feb. 15, 2021 – For people who closely follow the weather, the national weather map today is a rare one. An enormous winter weather system is moving eastward across southern, middle and northern portions of the country. More than 150 million Americans are currently under winter weather warnings or advisories, according to the National Weather Service (NWS).

The NWS states the area of hazardous winter weather is “unprecedented and expansive.”

NWS Bulletin (Feb. 15, 2021)
The following is part of the NWS bulletin issued at 3 a.m. EST today:

“An unprecedented and expansive area of hazardous winter weather continues into Presidents Day as disruptive snow and ice accumulations transpire across the South Central U.S. early this morning. This impressive onslaught of wicked wintry weather across much of the Lower 48 is due to the combination of strong Arctic high pressure supplying sub-freezing temperatures and an active storm track escorting waves of precipitation from coast-to-coast. While the current areas of snow and wintry mix over parts of the Southern Plains will conclude later this morning, bitterly cold temperatures will limit the amount of melting today, and thus treacherous travel conditions are likely to persist.

Heavy snow and freezing rain are forecast to advance northeastward today from the Mississippi and Ohio Valleys to the Northeast. A large swath of 6 to 12 inches of snow is forecast from the Ohio Valley and eastern Great Lakes to northern New England. South of the heavy snow axis, freezing rain is expected to cause a plethora of problems with over a tenth of an inch of ice in the forecast from far east Texas northeastward to southern New England. Significant ice amounts of a quarter to a half inch are expected in portions of the Lower Mississippi Valley and the Mid-South leading to dangerous travel conditions, numerous power outages, and extensive tree damage. Precipitation will likely stay rain for the southern Mid-Atlantic and Southeast where cold air is more limited.

In the West, another surge of Pacific moisture is accompanying a frontal system forecast to make  landfall along the Pacific Northwest coast this morning. More wintry weather is possible in lower elevations of the Pacific Northwest, while locally heavy rain could create localized flooding issues in far southwestern Oregon and far northwestern California early this morning. Farther inland, the Great Basin and Intermountain West can expect more rounds of higher elevation snowfall with the more intense snowfall rates occurring on Presidents Day.

Snowfall accumulations forecasts through Tuesday suggests 1 to 2 feet is likely in the Cascades and Northern Rockies through Tuesday (localized totals over 3 feet are possible), with measurable snow extending into the Wind River Mountains/Tetons, Wasatch, and Central/Southern Rockies as well. Avalanches remain a big concern in portions of Utah. This storm system is expected to be the next winter storm to impact the South Central U.S. mid-week.

The aforementioned Arctic high across the central U.S. is forecast to slowly moderate as the week progresses, but still maintain a firm and icy grip over the Heartland to open the week. Teeth-chattering cold temperatures are expected to continue between the Rockies and Appalachians through Tuesday with lows in the -20s and -10s for the Northern/Central Plains and Upper/Middle Mississippi Valley. Temperature anomalies are likely to be 25 to 45 degrees below normal for much of the central and southern Plains today with a carbon-copy of similar anomalies expected again on Tuesday. In addition, Wind Chill Warnings and Advisories reach as far south as the Southern Plains and as far east as the Ohio Valley. Hundreds of daily low maximum and minimum temperatures have been/will be broken during this prolonged “polar plunge,” with some February and even all-time low temperature records in jeopardy.”

Safety rules in winter weather
Sure it would be fun to test out the ice on a large lake or travel to a spot to go skiing. skating or sledding. But travel will be very difficult over the next couple of days. Cars breaking down in below freezing or below zero temperatures is an incredibly dangerous situation. If people do venture out, they should have a full tank of gas, blankets, water and food in case of an emergency breakdown. And most important, a fully charged cell phone is smart move. For people traveling to a remote location where cell phone coverage is spotty or nonexistent, it’s wise to have an emergency beacon or satellite phone. These devices do not rely on cell towers.

For winter weather safety tips, visit a NOAA Blog and the Centers for Disease Control and Prevention (CDC). Links can be found to the right.

UPDATE: Feb. 16, 2021 (8:00 a.m. EST): The storm barreled across the eastern half of the United States yesterday dumping feet of snow in some locations. And in many loactions, drifting snow piled up two to three feet high. Another storm is on the heels of yesterday’s storm. Below is the NWS forecast map issued today.

REVIEW QUESTIONS

1. What is precipitation?

2. How did the National Weather Service describe the area that will be affected by the winter storm?

3. Where is the most snow expected?

INQUIRY QUESTIONS

1. What are the factors that make winter travel during severe storms so treacherous? (Name at least three.)

2. How can people communicate if cell towers can’t operate?

3. Using stats in the story and at the US Census website, what percent of the American population is currently under winter weather warnings or advisories?

4. Compare the weather maps of Feb. 15 and Feb. 16 as noted in the story. What conclusions can you draw from that comparison?