Freeze Warnings Set for Saturday Night as Nor’easter Forms Off Carolinas

By
Harris
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Key Points

  • NWS Freeze Warnings run from about 1 a.m. to 9 a.m. EDT Sunday across much of the Ohio Valley, the Appalachians and parts of the Mid-Atlantic and Northeast.
  • Forecast lows include 25 to 30 degrees in central Pennsylvania and the upper 20s to low 30s in northern and western Maryland and northern Virginia.
  • Frost Advisories stretch from Illinois and Indiana to Kentucky, north Georgia and central Maryland, with lows in the low to mid 30s.
  • A nor’easter forming off North Carolina brings Coastal Flood Warnings for Hatteras and Ocracoke islands, where 2 to 4 feet of inundation is expected in low-lying areas.
  • Coastal Flood Watches cover the lower Chesapeake Bay and the Eastern Shore from Monday afternoon through Tuesday morning.

The coldest air of the season is settling over the eastern U.S., and Saturday night is when it bites hardest. As of 10:15 a.m. ET Saturday, the National Weather Service had Freeze Warnings posted from Indiana, Ohio and Kentucky through Pennsylvania, West Virginia, Maryland, Virginia and western North Carolina, plus parts of New York, New Jersey and Connecticut. Most run from 1 a.m. to 9 a.m. EDT Sunday.

The same pattern is spinning up a nor’easter off the Carolina coast, with coastal flooding forecast on the Outer Banks from Saturday evening into early next week.

What happened

A strong cold front is clearing the East Coast, ending a stretch of record and near-record warmth. NWS Wakefield said Norfolk tied its record high of 87 degrees on Friday. Behind the front, the NWS Weather Prediction Center said Saturday that highs will run 15 to 25 degrees below normal from the southern Plains into the Mid-Atlantic, Ohio Valley and Northeast.

In its Friday afternoon discussion, WPC said freeze and frost alerts covered much of the Plains, Upper Midwest and Great Lakes Friday night, and that the cold would spread into the Ohio and Tennessee valleys, the Appalachians and the Mid-Atlantic on Saturday night, “likely ending the growing season for many locations.” Warnings for lows of 26 to 30 degrees in parts of Colorado, New Mexico and West Texas expire Saturday morning.

Latest development

Where the NWS expects freezing temperatures early Sunday, per warnings posted Saturday morning:

  • Pennsylvania: 25 to 30 degrees across most of central Pennsylvania, as low as 26 in Lackawanna and Luzerne counties, and the upper 20s to around 30 in western Pennsylvania.
  • Ohio Valley: as low as 29 in parts of West Virginia, southeast Ohio and northeast Kentucky, the upper 20s and lower 30s in central and southwest Ohio, and 30 to 31 in northern Ohio and central Indiana.
  • Virginia, Maryland and North Carolina: the upper 20s and low 30s in northern and western Maryland and northern Virginia, and as low as 28 in southwest Virginia and northwest North Carolina.
  • New York, New Jersey and Connecticut: around 30 near Buffalo and Rochester away from the lakeshore, 30 to 32 in northwest New Jersey, the Lehigh Valley and the Poconos, and as low as 30 in New York’s Orange and Putnam counties and inland Connecticut.

Frost Advisories, with lows in the low to mid 30s, cover a band just south and west of those zones: counties south of Chicago and in northwest Indiana, Indianapolis, Louisville and central Kentucky, southern Illinois and western Kentucky, the north Georgia mountains, and central Maryland and Virginia.

The NWS warns that frost and freeze conditions “could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.”

Why it matters

Saturday night is the deadline to bring potted plants indoors, cover tender plants, drain garden hoses and shut off outdoor spigots or sprinkler lines. Outdoor pets need a warm, dry shelter. If you run a space heater, keep it away from anything that can burn and turn it off when you leave the room.

On the coast, the stakes are higher. NWS Newport/Morehead City said confidence is high in minor to moderate coastal impacts, with more significant impacts possible in vulnerable spots. Its Coastal Flood Warnings for Hatteras and Ocracoke islands run from 5 p.m. Saturday to 8 a.m. Tuesday and say vulnerable parts of NC 12 may be inundated around high tide, with a chance of people being stranded for multiple days. Dare County declared a state of emergency for Hatteras Island on Friday and ordered visitors off the island, WRAL reported. The NWS also expects 8 to 14 foot breakers and gusts up to 50 mph on the Outer Banks.

What happens next

Freeze Warnings end at 9 a.m. Sunday in most areas. NWS Mount Holly expects highs only in the 50s across the Philadelphia region Sunday and more frost possible Sunday night in the Poconos, Lehigh Valley and northern New Jersey.

The bigger question is how long the nor’easter lingers. NWS Wakefield expects tides 2 to 3 feet above normal and widespread minor to moderate coastal flooding early next week, especially Monday, and says a few locations could reach major flood stage. Its Coastal Flood Watch for the lower Chesapeake Bay, the lower James River and the Eastern Shore, including Ocean City, runs Monday afternoon through Tuesday morning, with one to two feet of inundation possible. Wakefield and Mount Holly forecasters both say the storm’s track remains uncertain.

Our guide explains how NWS watches differ from warnings. Out West, our earlier report on Southern California’s Santa Ana winds tracks a separate fire weather threat that WPC says lasts into Sunday.

Related live coverage

Follow freeze, frost and coastal flood alerts as they change on our U.S. Weather Live center. For live national news channels, visit the LiveNewsWorld Watch Live hub.

Sources