It's about to get life-threateningly cold for the first time this winter. Just how cold? The weather service has a new way to gauge.
An Arctic blast is expected to blow into the Lowcountry on Wednesday evening that's been hardening mercury in thermometers across the country. Temperatures will drop Wednesday night into Thursday to the lower 20s along the coast and the upper teens inland.
That's not the worst of it. Winds are forecast to be gusting to 15-20 mph, said meteorologist Steve Rawley of the National Weather Service, Charleston. "The temperature and the wind, that's what we're really concerned about."
Temperature and wind mean wind chill, the actual feel of the cold. The forecast on Monday called for a wind chill Wednesday on the coast of about 10 degrees, dropping to single digits as you move inland.
Frostbite, or freezing skin, and hypothermia will be real threats. Hypothermia is a serious drop in body temperature that can kill.
The solution is simple: Stay warm. Find somewhere heated inside. Outside, wear insulated coats, hats and the works. Don't leave pets out either.
Just in time for the lower temps, the weather service has revised wind-chill alert parameters for the Southeast to more accurately reflect the potential for life-threatening weather in the damper climes. Here they are:
Wind-chill watch: 15 degrees, coast; 10 degrees inland.
A watch means conditions could cause frostbite or hypothermia if precautions aren't taken, according to weather service postings.
Wind-chill warning: 0 degrees coast; 5 below zero inland.
A warning means conditions will cause frostbite, hypothermia and death if precautions aren't taken.
The old standards were 5 degrees below zero for a watch and 10 degrees below zero for a warning.
The cold blast isn't expected to break any records, Rawley said. But it is expected to have weather service meteorologists issuing wind-chill watches. And the cold isn't going to rush off. Temperatures on Thursday night are expected to be about as cold as Wednesday, but with nearly calm winds, the wind chill will be better.
Friday, the thermometer begins to climb again. Sunday, if not Saturday, will be back in the 50s in the daytime and above freezing at night. As for 60s? After Tuesday, don't get your hopes up.
"There's no more 60s as far out as we can see," Rawley said.
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