Hurricane Joaquin is expected to skirt the mid-Atlantic seaboard, but the region is not out of danger.
While forecasts suggest the hurricane will stay out to sea, a Nor'easter is already dropping heavy rain on the East Coast, adding to the threat from Joaquin. Five states — New Jersey, Maryland, Virginia and the Carolinas — already declared emergencies.
Five to 10 inches of rain was possible through Sunday along the Carolina coast, the National Weather Service said Friday afternoon.
Virginia's coast, especially the Hampton Roads region, is home to maritime industries and a large military presence. It is also a low lying area — much of the Chesapeake Bay region is vulnerable to flooding from heavy storms.
"We are still expecting rain and flooding in along the Eastern Shore and areas close to the coastline," said Taya Jarman, a spokeswoman for the Virginia Department of Emergency Management. "While we are breathing sigh of relief that we don't have a Category 5 storm coming, there is still pending danger. There is still significant rainfall. It has been raining for the past 72 hours and it will continue. Trees could fall over, which means we could have downed power lines. So we are not out of the clear. We still need people to prepare."
Jarman suggested that people in affected areas should keep emergency cash on hand and keep their tech devices charged in the event that the power goes out.
The department is deploying swift-water rescue boats to some coastal areas, and high-water vehicles are in places where roads might be washed out. Food, drinking water and cots are also being readied for use if people are evacuated. So far, the only region in the state that has issued mandatory evacuation orders is Lancaster County.
The Navy has an especially large presence in Virginia — the Norfolk Naval Base, where many of the Navy's major vessels are stationed; the Naval Amphibious Base at Little Creek, and Naval Air Station Oceana, which houses several squadrons of military aircraft.
The Navy has placed ships on "sortie condition bravo," meaning ships have to be ready to leave the area within 24 hours, said Lt. Stephanie Turo, a public affairs officer for U.S. Fleet Forces. The bases themselves have been placed on a higher level of storm readiness.
So far, the rain has not shut down the Port of Virginia, which handled about $70 billion of cargo in 2014, according to port spokesman Joe Harris in Norfolk.
The port has grounded empty containers and is checking generators and data centers in preparation, but the port remains open is going about "business as usual," Harris told CNBC.
The port expects to know sometime by Saturday morning whether the port captain needs to shut down the facility.
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So far, port officials are not too worried about flooding — some water may top the berth where ships dock, but port authorities are less worried about the weather than they were on Thursday, when forecasts were pointing to a direct hit by Joaquin.
"You get a forecast like that, it really gets your attention," Harris said.
There are five major oil and gas refineries along the East Coast that could be vulnerable if flooding hits the region. Combined, they account about 6 percent of the nation's total crude-refining capacity.
One of those plants is the 251,000 barrel-per-day refinery Phillips 66 Bayway Refinery in Linden, New Jersey. The company is keeping an eye on the weather and has plans in place should conditions worsen. They include deploying temporary offices, housing and computers in the event employees have to mobilize after a storm, according to Dennis Nuss, a spokesman for Phillips 66.
Other plants also are preparing. "We are monitoring the storm closely. We are following our hurricane preparedness plans, taking appropriate precautions based on the latest information," said Cherice Corley, spokeswoman for Philadelphia Energy. Corley would not give any further details.
Norfolk Southern announced it will delay the opening of an expansion in Rutherford, Pennsylvania, due to Joaquin-related weather, and has issued service alerts saying the company is watching for changes in the weather.
Norfolk Southern representatives did not return a call seeking comment.