A monster cold wave brought drastic changes to the Plains and Rockies already this week, but the cold will shift farther east this weekend.
Twitter was busy Friday morning with countless first snow pictures from the central part of the country, including the Denver metro area.
The cold wave fueling the snow across the Plains and Rockies will spread south and east through the weekend.
By Saturday night, the cold front initiating the cold wave will move off the East Coast as a much colder night advances into the Ohio Valley to the Appalachians.
For Chicago and Indianapolis along with surrounding areas, Saturday night will be the coldest since April.
"Normally, a freeze in early October in the Ohio Valley would cause problems with major agriculture, but they are nearly a month ahead of schedule because of the warm spring and hot summer," said Expert Senior Meteorologist and Agricultural Expert Dale Mohler.
"However, the cold wave will signal an end to the growing season for backyard gardeners," added Mohler.
Any remaining vegetables in gardens should be plucked off before the killing cold moves in.
While lows will gradually rise across the Plains Sunday night, the expanse of the cold weather will be at its greatest breadth.
Lows will tumble into the 30s from the Texas Panhandle, east into Tennessee and Virginia.
Cities such as Amarillo, Texas, to Springfield, Mo., and Nashville will tumble into the 30s Sunday night, all well below average for this time of the year.
It will be cold enough across the Northeast to support some of the first snow of the season Sunday into Sunday night.
Temperatures will rise to more seasonable levels next week for most, but areas from the northern Plains to the Great Lakes and Northeast will see repeated rounds of cold, bone-chilling air. An active northern branch of the jet stream will contribute to the repeated rounds of cold.
Conditions will deteriorate across Hawaii this weekend as Darby delivers locally heavy rain and rough surf.
The midwestern United States will be in the crosshairs of potent thunderstorms into Saturday night.
Much of the eastern United States will continue to swelter with above-average temperatures into the end of the month.
Stifling heat has been baking the central United States but will finally ease across northern areas this weekend.
Lightning killed a teenager on Friday, the second teen lightning death in three days. With thunderstorms continuing to rattle several parts of the nation, more lives will be at risk.
Montpelier, ID (1990)
75 mph winds gust; tree damage.
Seattle, WA (1991)
99 degrees, all-time record high for July.
Heat Wave: Location New Record(F): Old Record(F)/Year: Washington, D.C. 101 100/1987 Philadelphia, PA 99T 99/1978 Atlantic City, NJ 100 96/1987 Harrisburg, PA 103 98/1987 Baltimore, MD 103 98/1987 (Custom House)