Tropical downpours to drench eastern US ahead of Eta's arrival

Eta briefly became a hurricane on Wednesday in the Gulf of Mexico, but even as the tropical storm has made a second landfall in Florida, some moisture will break away from the hurricane and help to fuel heavy rainfall across parts of the eastern United States.

As Eta emerged off the northern coast of Cuba and passed through the Florida Straits over the weekend and into the beginning of the week, it helped to usher tropical moisture northward toward the southern U.S.

Before Eta made landfall over the Florida Peninsula, the high pressure area that brought a second summer to the eastern U.S. in recent days helped steer some of the tropical moisture northward. The push of tropical humidity arrived just in time to sync with a storm system projected to sweep into the East.

It will be the same storm that brought a sudden wintry chill and snow and ice to parts of the Midwest on Tuesday.

Tropical moisture is forecast to enhance rainfall from Tennessee and the Carolinas to southeastern New York, Connecticut and Rhode Island through Thursday. The heaviest rainfall developed across these areas on Wednesday night as the storm raced through.

Torrential rainfall led to ponding on roadways and reduced visibility. Some of the heaviest rain moved over the Interstate 95 corridor during Wednesday evening's rush hour. Motorists from Fayetteville, North Carolina, Washington, D.C., Philadelphia, New York City, to Providence, Rhode Island, dealt with difficult travel conditions.

On Wednesday, dam operators reported the potential failure of the College Lake Dam in the City of Lynchburg, Virginia, along the Blackwater Creek. Officials state that if the dam fails, the Blackwater Creek could reach 17 feet in a matter of minutes.

CLICK HERE FOR THE FREE ACCUWEATHER APP

Some commuters along much of the stretch of Interstate 95 may face more drenching rain during Thursday's commutes.

During the afternoon the rain will retreat toward the immediate New England and upper mid-Atlantic coasts. However, rain is forecast to continue into the afternoon and evening over the interior Southeast, including part of the I-85 corridor.

Rainfall totals of 1-2 inches will be common across this region through Wednesday night. However, 2-4 inches of rain is likely across portions of the mid-Atlantic where heavy rain will linger into Thursday, especially along the southern- and eastern-facing slopes of the Appalachian Mountains in Virginia and North Carolina.

This amount of rainfall can also lead to areas of flash flooding. The Charlotte, North Carolina, areas was hit hard by heavy rain and flash flooding during Wednesday night and Thursday.

Areas of downpours are expected to linger over parts of the mid-Atlantic and Southeast through Thursday, but a drier and cooler air mass will arrive on Friday in the Southeast. A second dose of rain may drench coastal areas from the mid-Atlantic to New England for at time on Friday as Eta's moisture rolls northeastward.

With the arrival of cooler air, temperatures are expected to trend toward normal levels through the end of the week and into the weekend. This will be nearly a 20-degree temperature drop in some locations between Wednesday afternoon and Friday afternoon.

Normal temperatures for this time of year range from 54 F in Boston to 61 F in Washington, D.C.

Record highs were challenged for the fourth day in a row across parts of the East on Tuesday ahead of the change in the weather pattern. Central Park soared to 75 F, tying a record from 1975 on Monday. On Tuesday, the previous record high of 73, set in 1983, was broken with a high of 74. Other nearby locations shattered old record highs, including Newark, New Jersey, and Islip, New York, which had stood since 1975 at 77 and 74, respectively.

Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.

Report a Typo