A historic winter storm is inching north up the Eastern Seaboard on Friday, threatening the nation’s busiest corridor with two feet of snow and prolonged white-out conditions. The National Weather Service has issued blizzard warnings for every major city from Washington, D.C., to New York. Storm surge could reach 5 feet on the Mid-Atlantic coast. Freezing rain is coating the Carolinas in thick, dangerous ice.

Authorities along the East Coast declared states of emergency and announced preparations for the storm, vowing to be ready and issuing dire warnings urging people to avoid travel. Thousands of flights were canceled, while officials announced plans to halt or reduce transit service on the ground due to the storm.

The Washington, D.C., region is in the bulls-eye, expecting up to two feet of snow, with the potential for more. This is more snow than the region has seen since the crippling, exhausting winter of 2009-2010, when “Snowmageddon” dumped nearly 18 inches on the capital. That could pale in comparison to the snow that falls this weekend.

Washington’s snowiest storm on record came in 1922, when 28 inches fell on Jan. 27-29 — the infamous Knickerbocker storm, named for the theater that collapsed under the weight of snow and killed 98 moviegoers.

D.C. has earned a reputation for freaking out about snow. But these five snowstorms proved to be worthy of the frenzy they caused. (Claritza Jimenez/The Washington Post)

While the inches accumulate, gusty winds will drive blowing snow and lead to white-out conditions. The National Weather Service has issued a blizzard warning for the entire D.C.-Baltimore region, noting that “conditions will be a threat to life and property.” Wind gusts could reach 55 mph.

 

Capital Weather Gang's Jason Samenow gives the latest forecast and snow accumulation predictions for the potentially historic blizzard hitting the Washington area and the mid-Atlantic. (Jayne Orenstein,Jason Samenow/The Washington Post)

At the coast, a different threat is taking shape. Wave heights near shore could reach 15 or 20 feet this weekend. Powerful onshore winds could lead to hurricane-like coastal flooding. Making matters worse, the prolonged nature of the storm means that winds will be blowing onshore for three high tides. And it’s nearly a full moon. Forecast models are predicting a storm surge of 4 to 5 feet in Delaware, and 3 to 4 feet in southern New Jersey.


A simulation of storm surge Saturday early afternoon. (NOAA Ocean Prediction Center)

Moderate to major flooding is possible in coastal and back bay areas of Delaware and New Jersey during high tides from Saturday morning through Sunday morning. The National Weather Service cautions that numerous roadways could be flooded and inaccessible, and that powerful waves may significantly erode the beaches.

North of the Mid-Atlantic, snow totals will be lower but winds will be no less punishing. A blizzard warning is in effect for Philadelphia, all five boroughs of New York City and Long Island.

In Philadelphia, snow could top a foot. Snow accumulation is expected to be anywhere from 7 to 12 inches in the NYC area, but winds will be howling from the northwest, gusting to 55 mph. Visibility could drop below 1/4 mile at times between Saturday morning and Sunday afternoon.

In New York, the storm begins Saturday morning and reaches maximum intensity Saturday night, with snow expected to taper off mid-afternoon Sunday. People in the area should expect “extremely dangerous travel due to heavy snowfall and strong winds,” the Weather Service said Thursday.

To the south, the forecast becomes much more icy. The Carolinas will be ground zero for freezing rain — only a few tenths of an inch, but that’s all it takes to bring down branches, topple power lines and turn roads dangerously slick. In Charlotte, N.C., ice began to accumulate early Friday morning. At least 1/4-inch of freezing rain is all but certain, and some models suggest as much as one inch.

As the storm exits the Southeast on Saturday, the temperature will drop further and freezing rain will change over to light snow, which will freeze surfaces solid.

READ MORE:

The laws and fines for not shoveling snow in the D.C. area

How to protect yourself and your home

What to do if you see someone who needs help in freezing weather

Donate to your local shelter before the storm hits

This story has been updated.