Big snow for southern Mid-Atlantic beaches midweek, a likely miss for D.C.

The latest arctic outbreak penetrating deep into the southern U.S. is setting the stage for a rare major winter storm from the Gulf Coast to the southern Mid-Atlantic.

This storm is likely to remain south of the Washington, D.C. and Baltimore areas.  The northern edge of the storm will probably span from around Richmond, Va. to Salisbury, Md. although small shifts north or south are possible.

 

A wave of low pressure will form along the arctic front tonight in the Gulf of Mexico and then head east and northeast offshore the George/South Carolina coast. Just to the north and west of this wave, wintry precipitation is expected.

Forecast weather map Tuesday morning (National Weather Service)

Forecast weather map Tuesday morning (National Weather Service)

Winter storm watches span from Houston and Galveston, Texas to Virginia Beach, and cover New Orleans, Mobile, Atlanta, and Charleston.  Winter storm warnings have already been hoisted from Myrtle Beach to the North Carolina Outer Banks.

“For Charleston, S.C. and Savannah, Ga., it’s the first winter storm watch issued for those two cities since Feb. 11, 2010,” notes The Weather Channel.

Area under winter storm watches (blue) and warnings (pink) (National Weather Service)

Area under winter storm watches (blue) and warnings (pink) (National Weather Service)

Model simulations suggest snow totals exceeding 6 inches, and possibly even double digit totals from east central South Carolina through eastern North Carolina.

European model snowfall simulation (WeatherBell.com)

European model snowfall simulation (WeatherBell.com)

GFS model snowfall simulation (WeatherBell.com)

GFS model snowfall simulation (WeatherBell.com)

High resolution NAM model snowfall simulation (WeatherBell.com)

High resolution NAM model snowfall simulation (WeatherBell.com)

The National Weather Service is officially forecasting around 4-8 inches of snow in this coastal Carolina zone, from Tuesday morning to Wednesday morning.

“Climatology suggests this scenario is very favorable for heavy snow across eastern NC… And model guidance is all in agreement to some degree with heavy snow occurring across the area,” writes the National Weather Service forecast office in Morehead City, N.C.

Probability of at least 4 inches of snow Tuesday morning to Wednesday morning (National Weather Service)

Probability of at least 4 inches of snow Tuesday morning to Wednesday morning (National Weather Service)

For the Gulf Coast, some snow is possible Tuesday, but freezing rain and sleet are likely to be the more prevalent hazards.

“Travel conditions are expected to become difficult due to icy roads and bridges during the day on Tuesday. In areas where significant freezing rain occurs…sporadic power outages are possible. The highest potential for freezing rain will be across southeast Louisiana south of Lake Pontchartrain including the city of New Orleans,” writes the National Weather Service forecast office serving New Orleans.

Probability of at least 0.10" of freezing rain between Tuesday and Wednesday morning (National Weather Service)

Probability of at least 0.10″ of freezing rain between Tuesday and Wednesday morning (National Weather Service)

For areas right along the Gulf coast, there’s some uncertainty about exactly how much cold air will filter in. It’s possible they’ll dodge the bullet with more rain as opposed to frozen precipitation.

Storm impacts forecast the Mobile-Pensacola region (National Weather Service)

Storm impacts forecast the Mobile-Pensacola region (National Weather Service)

Irrespective of exact locations of snow versus rain versus ice, the storm is likely to have a high impact in areas unaccustomed to significant winter weather. Writes CWG contributor Dennis Mersereau, who’s currently in Mobile:

The deep south…gets snow and ice so rarely that it’s truly a big deal down here. Take Mobile AL (where I go to school) for instance. We don’t have plows. We don’t have salt trucks or even a stockpile of salt for the roads. Nobody has snow shovels. The grocery stores don’t sell rock salt or shovels or even many winter clothes. It just doesn’t snow here, and when it does, it’s usually not a lot. This is true of many areas in the deep south that rarely (if ever) get winter weather.

This is a big deal.

The storm exits the Carolinas Wednesday morning, with moderating temperatures over the entire region from the Gulf Coast into the southern Mid-Atlantic Thursday and Friday.

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