The coldest air of the winter will plunge southward across much of the eastern United States and will feature single-digit and sub-zero temperatures in the Northeast during the Valentine's Day weekend.
The polar vortex will send a dose of frigid air southward beyond Canada. Some of the air will slide directly southward from eastern Canada and avoid any warming effects of the milder waters of the Great Lakes.
New England, the mid-Atlantic and part of the Southeast states are about to have a reality check.
Following a month so far with temperatures averaging 5-10 degrees Fahrenheit above normal, temperatures during the Valentine's Day weekend will plunge to 10-20 degrees below normal. Temperatures will be 30 degrees lower this weekend, when compared to highs at midweek.
The cold air will be dangerous for those spending time outdoors not properly dressed. In addition to the dangers from frostbite and hypothermia, the magnitude of the cold air can cause unprotected pipes to burst, water mains to rupture and batteries to die in vehicles.
The direct shot of arctic air will yield below-zero temperatures on one or more nights from the central Appalachians to much of New England.
Lows in the single digits are in store from parts of northern and western Virginia to the Interstate-95 corridor of the mid-Atlantic, including the New York City, Philadelphia, Baltimore and Washington, D.C., metro areas.
According to AccuWeather Meteorologist Edward Vallee, "High temperatures in the I-95 mid-Atlantic corridor will struggle to reach the lower 20s by Sunday and may not reach 10 over the interior."
Wind and other factors will make it feel even colder. AccuWeather RealFeel® Temperatures will dip to 10-20 degrees Fahrenheit lower than the actual temperature at times.
This will translate to RealFeel Temperatures well below zero over the interior Northeast during much of the weekend and barely above zero for a few hours during the afternoon hours near the Atlantic coast.
RealFeel Temperatures can dip to minus 30 or lower in parts of upstate New York and New England during Saturday night.
Temperatures will dip into the teens as far south as parts of the Carolinas and northern Georgia.
At this time, it appears freezing temperatures will avoid the fruit and vegetable growing areas of central Florida during the weekend. However, temperatures could dip to frosty levels on a couple of occasions during the middle of this week, where and when skies are clear and winds are calm at night.
"Temperatures low enough to cause damage in the citrus growing areas of Florida are not likely this week," according to AccuWeather Senior Meteorologist Dale Mohler.
"Temperatures could get low enough over unprotected fields of berry fruits and vegetables of north-central Florida to cause only spotty, minor damage north of Orlando at worst during the middle part of this week," Mohler said.