Thunderstorms Threaten East With Flight Delays, Floods

A line of thunderstorms that touched off tornadoes, knocked out power to thousands and grounded hundreds of flights across the Midwest is bringing rain and potential flooding to the East Coast, including Washington and New York.

Rain falling in New York during the day will become more intense overnight and into tomorrow, according to the National Weather Service. Two to 3 inches (5 to 8 centimeters) may fall, with some locations receiving more.

“Low pressure will intensify as it approaches from the Ohio Valley today and pass south and east of Long Island tonight through Friday morning,” said a weather service flood watch for New York. “This system is expected to produce heavy rain at times.”

Just before 7 a.m. New York time, planes were being held at their origin airports for flights to New York LaGuardia, New Jersey’s Newark Liberty, Philadelphia, Baltimore-Washington International and Washington’s Reagan National and Dulles International because of “weather/thunderstorms,” according to the U.S. Federal Aviation Administration’s travel website.

Delays on inbound flights to LaGuardia averaged 94 minutes, said, a Houston-based tracking service.

Southwest Airlines Co., which had 100 flights delayed or diverted by the storm in Chicago yesterday, expects to see more delays in Baltimore and Philadelphia, said Whitney Eichinger, a spokeswoman for the Dallas-based airline. American Airlines Inc. has dropped a “handful” of flights today and doesn’t expect widespread cancellations, said Matt Miller, a spokesman based in Fort Worth, Texas.

Storm Damage

The system spawned tornadoes across Iowa, Illinois and Ohio yesterday, damaging buildings, snapping trees and downing power lines, according to the U.S. Storm Prediction Center in Norman, Oklahoma. Large hail and gusts as intense as 72 miles (116 kilometers) per hour were reported across the region.

At least 593 flights into and out of Chicago’s O’Hare International and Midway airports were canceled yesterday, FlightAware said.

More than 66,000 customers in Chicago and northern Indiana were without power yesterday, according to utility reports. An additional 58,000 customers lost power in Pennsylvania and Ohio.

Flood warning and watches stretch today from Massachusetts to Virginia. An area from central New Jersey to northern Virginia, including Philadelphia, Baltimore and Washington, has a 45 percent chance of high winds, hail and possibly tornadoes, according to a storm center forecast.

Meteorologists had feared yesterday’s thunderstorms would coalesce into a derecho, characterized by winds of at least 58 miles (93 kilometers) per hour, creating a line of damage at least 240 miles long. A derecho swept through the Midwest into the mid-Atlantic a year ago, knocking out power to 5 million people from Chicago to Washington and killing 22, according to government data.

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