The coldest blast of air since spring is expected to affect millions of people in the United States.
Prolonged cold spells of fall have been recorded in many areas of the United States since the beginning of fall in September.
However, CNN's latest weather report indicates that the combination of an expanding cold front and a cold front from Canada will change the weather situation in the US, with temperatures likely to drop further below average by midweek.
As of the morning of October 15, more than 60 million people from the Plains to the Appalachians and the northeastern region of the United States are under frost or freeze warnings as temperatures drop.
The latest cold front swept across the northern-central United States through the eastern half of the United States on October 14. Further cold air from Canada was pushed further south throughout October 15 and 16.
In Chicago, October 15 was considered the coldest day of the week in Chicago, with a high of around 10 degrees Celsius. Except for October 14, when the temperature was 14 degrees Celsius, Chicago has not recorded a temperature above 10 degrees Celsius since April.
Temperatures are forecast to drop again on October 16 for many areas outside the Midwest. October 16 is expected to be the coolest day since spring for millions of people in the United States. In many places, the weather will feel more like late November than October.
"True fall-like weather is forecast through the weekend" farther south, the National Weather Service in Atlanta said.
The high temperature in Washington, D.C. on October 16 is forecast to top out at 5 degrees Celsius, well below normal for mid-October.
October 16 will also be the coldest day of the week for much of the northeastern United States, with highs in the 40-50 degree range in many areas. With daytime temperatures this cold, overnight temperatures could dip below freezing. The cold could bring some snow from the highest elevations of West Virginia to New York and New England.
"Icy and freezing conditions are possible for a few nights and in many areas this week," the National Weather Service in State College, Pennsylvania, warned.
Millions of people have been warned of frost and ice this week and more warnings are likely in the coming days.
Freezing or near-freezing temperatures are possible every night from Oct. 15 to Oct. 17 in western North Carolina, which was devastated by Hurricane Helene late last month.
Temperatures will drop back to normal October levels this weekend across much of the central and northeastern United States. The cold front will last until at least October 18, with areas as far south as the Appalachians and the southeastern United States.
CNN's Weather Forecast shows that by October 19, seasonal high temperatures of 70-80 degrees Fahrenheit will return to the southeast while temperatures of 60-70 degrees Fahrenheit will be common in the north into the Midwest and parts of the northeast of the United States.
