|Surface temperatures at 6:00 a.m. CST on February 19.|
The lowest temperature this morning in the lower 48 states was -42°F in Cotton, MN, about 36 miles north of Duluth. Duluth's high temperature of -5°F today tied the record low maximum first set in 1941.
|Minimum temperatures for the 12 hr period ending at 6:00 a.m. CST February 19.|
|Surface temperatures at 3:00 p.m. CST February 19.|
The wide extent of the cold air is due to a huge upper level trough over the eastern two-thirds of the country. As can be seen on the chart below, the air, which flows parallel to the lines on the map, is coming straight over the Arctic and into Canada and the U.S.
|500 millibar map for 6:00 p.m. CST February 19.|
More records are likely Friday morning especially across the eastern U.S. where clear skies and snow cover will allow the temperature to plummet. Clouds spreading across the Midwest will slow the temperature drop there. Hard freeze warnings are in effect from southern Alabama through the northern half of Florida.
|Forecast minimum temperatures for Friday, February 20.|
While the intensity of the cold air is bad enough, the persistence of the cold air is a real problem for an area from the Ohio Valley southeast into Tennessee, Georgia, and western North Carolina where freezing rain from the storm earlier this week caused power outages. Unfortunately, it appears that more icing could occur this weekend from Ozarks east through Tennessee into North Carolina and Virginia.
|Forecast for the period from 6:00 p.m. CST February 19 to 6:00 p.m. CST February 22.|
|Minimum temperature forecast for Thursday, February 26.|