Atmospheric river brings weather whiplash to East Coast as bomb cyclone develops

PORTLAND, Maine — The U.S. East Coast began a whiplash-inducing stretch of weather Wednesday with a deluge of rain, rapid snowmelt and powerful gusts, creating dangerous conditions, due in part to an atmospheric river and developing bomb cyclone.

Ski resort operators in the Northeast watched their snow turn to mush with a deluge of rain and unseasonably high temperatures — followed by damaging winds — all in the same day, part of a powerful storm system that stretched from Florida to Maine.

Utilities braced for widespread power outages with winds projected to exceed 60 mph (97 kph) through late Wednesday. Isolated severe thunderstorms were possible southward into portions of Florida. Elsewhere, heavy lake effect snow was expected through Thursday in parts of Michigan, along the Lake Michigan shoreline, and dangerous cold enveloped parts of the Upper Midwest.

A key driver in the weather was an atmospheric river, which is a long band of water vapor that can transport moisture from the tropics to more northern areas, said Derek Schroeter, a forecaster with the National Weather Service. New England was bearing the brunt as the storm tapped moisture from the Atlantic Ocean off the coast of the U.S. Southeast, and transported it to places like Maine, he said.

Forecasters also said the storm had the potential to include a process that meteorologists call bombogenesis, or a “bomb cyclone.” That’s a rapid intensification of a cyclone in a short period of time, and it has the ability to bring severe rainfall.

“Is that what they’re calling it?” said Jen Roberts, co-owner of Onion River Outdoors sporting goods store in Montpelier, Vermont. She lamented that a five-day stretch of snowfall that lured ski customers into the store was being washed way, underscoring the region’s fickle weather. “But you know, this is New England. We know this is what happens.”

Alex Hobbs, 19, a Boston college student, hopes that the weather won’t interfere with her plans to return home to San Francisco soon.

“I’m a little worried about getting delays with heavy wind and rain, possibly snow,” she said Wednesday.

In New England, the storm began with combination of fog and freezing rain Tuesday night into early Wednesday, making travel treacherous. A tractor-trailer carrying a load of oranges went off the Maine Turnpike in New Gloucester; the road was so treacherous that the oranges couldn’t be removed until a day later.

In New Hampshire, the Mount Washington Avalanche Center issued a special bulletin Wednesday for the Presidential Range of mountains, which received significant snowfall over the last two weeks. “Heavy rainfall could create dangerous and unpredictable avalanche conditions on steep snow-covered slopes,” the avalanche center warned.

Flood watches were in effect in Vermont, where the capital city of Montpelier, hard hit in past floods, advised residents to elevate items in basements and low areas that are prone to flooding. And in Rhode Island, heavy surf and flooding closed several roads in Newport.

Ski resorts around the Northeast were preparing visitors for a potentially messy day on Wednesday. “We don’t say the ‘r-word’ around here. It’s a forbidden word,” said Jamie Cobbett, marketing director at Waterville Valley Resort in New Hampshire. “We’re getting some moist wet weather today. We’ll put the mountain back together tonight, and hopefully we’ll be back skiing tomorrow with no problems.

At Vermont’s Sugarbush resort, skier Marcus Caston was waterlogged but shrugged it off. “The conditions are actually pretty good. The rain is making the snow nice and soft. It’s super fun,” he said. “We’re having fun out here.”