The weather outlook for the eastern U.S. is starting to resemble the plot of a 1970s disaster movie in which everything that could go wrong did.

From the mid-Atlantic to the Northeast, the coastal states have been soaked by rain. While this is happening, Hurricane Joaquin lurks in the shadows, passing over water that is just perfect for it to strengthen explosively. No one can say where it will go.

On top of that, high pressure in Canada and low pressure in the southern U.S. will conspire to slam the surf onto land, eroding beaches and keeping water pinned along the shoreline. As that happens, another round of rain could leave 2.5 inches (6.4 centimeters) in New England to as much as 5 to 8 inches from New Jersey to North Carolina.

“There’s certainly going to be a lot of rain before Joaquin even gets here,” said Bruce Terry, a senior branch forecaster at the U.S. Weather Prediction Center in College Park, Maryland.

Insurance Costs

From Maine to North Carolina, about $15.7 trillion of insured coastal property is exposed to any potential storms that come up the East Coast, according to the Insurance Information Institute of New York.

Things could easily go from bad to worse and the price tag could get pretty high. “Joaquin is the wild card,” Terry said.

The problem is right now, no one is sure where the hurricane will go.

The European Centre for Medium-Range Weather Forecasts’ computer model has been predicting the storm will move away from the U.S. Other models predict it will strike along the East Coast, said Phil Klotzbach, author of Colorado State University’s seasonal hurricane forecast along with Bill Gray.

“Since the ECMWF is generally considered to be the best track model, it’s a really tough call,” Klotzbach said.

Balloons Launched

At 2 p.m. Wednesday, several National Weather Service offices made special weather balloon launches to help gather more information to firm up the outlook. The National Hurricane Center’s official track forecast called for the storm to near Delaware by Monday morning.

Once the storm starts moving north, however, it can speed up, and the forecasters at the center said there isn’t a lot of confidence in that outlook. Under normal conditions, five-day track forecasts can be off by 200 miles.

Then there is Joaquin’s strength.

Klotzbach said Joaquin is passing over a deep layer of warm water in the Bahamas that will allow it to grow strong. The storm’s winds doubled in strength in just about 30 hours.

“This falls into the category of what Bill Gray terms a Bahama Buster,” Klotzbach said. “These are weak tropical cyclones that intensify rapidly over the deep warm water near the Bahamas.”

Altogether, the situation is this: a rapidly strengthening storm bearing down on a region reeling from heavy rains and floods while the best computer models available to forecasters can’t agree on what will happen next.

There is one bright spot, said Paul Walker, a meteorologist with AccuWeather Inc. in State College, Pennsylvania.

Much of the East Coast didn’t seen rain for most of September, so river levels have been low. This may provide some extra room to absorb the deluge before they start to spill their banks, he said.