Huge swathes of the Midwest, Great Plains, South, and Northeast are in the grips of a cold snap, with Freeze Warnings affecting 17 states and Frost Advisories stretching into New England.
Freeze Warnings are put into place when “significant, widespread freezing temperatures are expected,” while a Freeze Watch is issued when “there is a potential for significant, widespread freezing temperatures within the next 24-36 hours,” the NWS said. A Frost Advisory is given “when the minimum temperature is forecast to be 33 to 36 degrees [Fahrenheit] on clear and calm nights during the growing season.”
Freeze Warnings have been issued for much of North Dakota, South Dakota, Minnesota, Wisconsin, Iowa, Kansas, Missouri, Nebraska, Illinois, Michigan, Indiana and Ohio, as well as small sections of Oklahoma, Texas, Arkansas, Virginia, West Virginia, North Carolina, and Kentucky. Freeze Watches have been given to parts of Kansas, Nebraska, Colorado, Illinois, Nevada, and California.
Frost Advisories have been issued in Missouri, Illinois, Indiana, Kentucky, West Virginia, Pennsylvania, Maryland, New Jersey, New York, and Connecticut, with small parts of Virginia, Arkansas, North Carolina, Ohio, Wyoming, and Nebraska also receiving Frost Advisories.
“A mid-October chill will be noticeable across much of the central and eastern U.S. over the next few days as highs struggle to reach above the 50s for most locations. Low temperatures are also expected to dip well below average for this time of year and into the 30s, leading to widespread frost/freeze opportunities between the Midwest and mid-Atlantic,” the National Weather Service said in a Short Range Public Discussion.
The majority of the Freeze Warnings are in place between around 1 a.m. and 9 a.m. CDT on Wednesday, but some end at 9 a.m.
Temperatures are expected to drop as low as 26 degrees Fahrenheit in some parts of Nebraska, Iowa, Minnesota, South Dakota, and Kansas, and may fall to 25 degrees Fahrenheit across portions of Minnesota, South Dakota, Kansas, Illinois, Iowa, Missouri, Nevada, and California.
“Subfreezing temperatures as low as 24 [degrees Fahrenheit] expected [across] portions of central, northwest, and west central Minnesota and northeast and southeast North Dakota,” the NWS said.
The cold weather advisories are issued only until the end of the growing season in the fall, which comes with the first widespread freeze.
“The normal end of the growing season is mid to late October west of the Blue Ridge and early November east of the Blue Ridge. However, during anomalously warm autumns, the growing season may be extended past the normal end of the growing season,” the NWS said.
When temperatures approach freezing, frost may form, which can damage crops and plants by bursting their cells.
“Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered,” the NWS said in the Freeze Warning. “Take steps now to protect tender plants from the cold.”
Additionally, freezing weather can damage pipes, which may need to be protected ahead of the cold snap.
“To prevent water pipes from freezing, wrap or drain or allow them to drip slowly,” the NWS said.
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