A storm will rapidly strengthen as it moves north from the United States into Canada. The burgeoning bomb cyclone will unleash torrential rains and strong winds from the Appalachian Mountains to the Atlantic Coast, hampering travel, triggering flooding and causing power outages during the week, AccuWeather meteorologists warn.

The start of the storm brought torrential rain and severe thunderstorms from Louisiana to Georgia early Tuesday. Tornado warnings were issued for some thunderstorms. Damaging winds and flash flooding in cities will be the main threats from the storms in the Southeast through Tuesday night.

As downpours and thunderstorms began to develop across the Southeast Tuesday evening, the rain began to extend northward, drenching the central Appalachians, mid-Atlantic and southern regions of New England.

The storm will quickly reorganize and strengthen along the upper Mid-Atlantic coast on Wednesday. The storm’s central pressure will drop, creating a huge vacuum in the atmosphere that will produce winds. If the central pressure drops to 0.71 inches of mercury (24 millibars) in 24 hours or less, that storm is projected to occur. To do this, bombogenesis occurs and the formation of a bomb cyclone occurs.

“Some rainfall will act like a giant fire hose, forming into an intense north-south and west-east squall with gusty winds,” AccuWeather Chief On-Air Meteorologist Bernie Rayno said.

Enough rain will fall – generally 1 to 4 inches – to raise the water levels of streams, rivers, lakes and reservoirs and trigger urban flooding. The AccuWeather Local StormMax™ rainfall for this storm is 6 inches in the southeast and 8 inches in the northeast.

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A plume of moisture will likely be tracked for more than 2,000 miles – from the northeastern United States to the Caribbean Sea – and “meet the definition of an atmospheric river,” Rayno added.

This advancing thunderstorm poses the highest risk of accidents on the roads and ground stops at some airports. Puddling, severely reduced visibility and even thunder and lightning may accompany the thunderstorm along the Interstate 95 corridor. The fog alone has already caused delays in some locations and will continue or continue until the storm moves away on Wednesday evening.

“Locally severe thunderstorms are possible along the Northeast coast on Wednesday, with the possibility of a few tornadoes in parts of the Mid-Atlantic,” Rayno added.

While much of the heavy rain will fall east of areas around the Great Lakes that have seen several feet of snow fall in recent weeks, some rain will reach northern New England.

“The risk of significant flooding becomes even greater in the higher elevations of Vermont, New Hampshire and Maine, where there is significant snow cover of several inches on the ground. Rapidly melting snow can add another 1 to 2 inches of liquid water to the runoff, and particularly in areas with steep terrain, rapidly rising water can cause life-threatening flooding, said AccuWeather Chief Meteorologist Jonathan Porter.

Rain can also significantly increase the load on roofs that have not been cleared. This additional weight could cause roof failure on flat or low-angle gables.

Even without snow on the ground, the firefighting effect of rain alone can cause significant flooding in cities and small streams from Delmarva to New England, including the major metropolitan areas of Philadelphia, New York City, Boston, Providence, Rhode Island and Hartford. Connecticut. Driving on flooded roads can not only result in the destruction of vehicles but can also become a life-threatening situation.

This storm may experience strong wind gusts without any thunder or lightning. The strongest wind will blow from the south along the Atlantic coast from Wednesday afternoon to Wednesday evening. In this zone from eastern North Carolina to southeastern Maine and the Maritime Provinces of Canada, gusts will frequently fluctuate between 50 and 70 mph, with an AccuWeather Local StormMax™ gust of 85 mph.

Further west, there may be mostly light winds over the central Appalachians on Wednesday. However, as the storm center moves toward Canada and drops bombs, strong winds will occur from the west and northwest with speeds of 30 to 50 miles per hour and locally stronger gusts. The same gusts will reach the Atlantic coast later Wednesday evening and Thursday.

While sporadic power outages may occur in the Midwest and Northeast as the storm strengthens, the greatest risk of regional problems, including damage to property and holiday decorations, is in the coastal areas of the Northeast and particularly eastern New England.

The storm’s impacts in coastal areas of the Northeast will be similar to that of a strong tropical storm or landfill-filling hurricane.

People are urged to secure Christmas decorations as well as trash cans, wastebaskets, tarpaulins and trampolines to prevent them from becoming flying projectiles that can injure people or damage property.

As a result of the storm, arctic air is moving in from the Midwest and can trap the moisture behind the storm.

Aside from a period of heavy lake snow Wednesday night through Friday, a general blast of snow Wednesday into early Thursday from the eastern portion of the Ohio and Tennessee Valleys to the Appalachian Mountains may quickly cover roads and make driving slippery. Click here for more information about the Arctic air and snow following the storm.

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