East coast of America braces for a 'bomb cyclone' of freezing weather

Harriet Alexander
Pennsylvania saw two days of record-breaking snow in the town of Erie over the Christmas period. The east coast is braced once again for more freezing weather - REUTERS

Move over, Polar Vortex: there is a new big freeze brewing.

Forecasters in the United States are warning of a "bomb cyclone", which they say will send the already-freezing temperatures along the east coast plummeting further.

Blizzards, ice and snow are expected in storms forecast to hit New England overnight on Wednesday, after snow fell on Wednesday in Florida for the first time in more than a quarter of a century.

Meteorologists coin the term because the storm's pressure is predicted to fall so fast - an indicator of explosive strengthening.

The storm could rank as the most intense over the waters east of New England in decades, for this time of year.

National Weather Service hurricane hunter aircraft are even flying into the storm to gather data and refine the forecast given the possible severe impacts in coastal areas.

Ryan Maue, of the US weather service, tweeted: "Rapidly developing 'bomb cyclone' off US east coast will see pressure drops > 24 millibars / 24 hours (probably closer to 40 or 50 mb), hurricane forces winds, blizzard conditions with heavy snowfall along coast during next 48-hours."

He added that the coming storm would be "in the upper echelon of 'bomb cyclones'" - adding that the term refers to "simply a more extreme variety of 'cold season' storm that usually harmless mix fish, generate huge waves, and do their job of moving Earth's heat."

New York City was expecting three to six inches of snow overnight on Wednesday, but the storm was giving rise to predictions of such outlandish weather that one forecaster, Eric Fisher, based in Boston, described as “bananagrams” the outlook for northern Florida.

“If this verifies . . . an unreal event for this part of the country,” he tweeted.

In the Florida city of Tallahassee it was snowing for the first time in 28 years on Wednesday morning.

Ice and more than three inches of snow could fall in Savannah, which would make history.

“In almost 150 years of record keeping, the snowiest day in Savannah is only 3.6 inches,” tweeted Greg Diamond, a meteorologist at the Weather Channel.

The Weather Service storm prediction center issued a rare alert for “heavy freezing rain” along the entire South Carolina coast on Wednesday morning, with up to eight inches of snow predicted along the Maryland and Delaware beaches.

The Virginia Tidewater region issued what was only its second blizzard warning since the 1980s, with experts saying that the combination of wind gusts up to 50 mph and heavy snow could cause whiteout conditions.

Forecasters were also warning of fierce winds and storm surges.

“Some computer models are projecting a minimum central air pressure of below 950 millibars at its peak, which would be nearly unheard of for this part of the world outside of a hurricane,” said Andrew Freedman, writing on Mashable. “For comparison, Hurricane Sandy had a minimum central pressure of about 946 millibars when it made its left hook into New Jersey in 2012.”

It is this drop in pressure that will cause winds to whip across eastern New England, with gales of up to 60 to 70 mph along the coast.

Winds will be considerably stronger over the ocean - exceeding hurricane force - where enormous waves will form. Seas could rise by over two feet in coastal Massachusetts and Maine.

Finally, after one of the most intense cold spells of such duration on record in parts of New England, including Boston, temperatures are forecast to gradually thaw by early next week.