A severe thunderstorm turned deadly Monday night in Wilmington, Delaware, when a falling tree killed a 79-year-old woman riding in a car, Delaware State Police said.

       Meteorologists warn the storm marks the beginning of a dangerous weather pattern along the Eastern Seaboard.

       The crash happened about 10:08 p.m. on Lancaster Pike when the storm caused a tree to fall into the path of an SUV, according to state police. The driver, a 79-year-old man from Newark, Delaware, tried to swerve but couldn't avoid the collision, police said.

       The driver was taken to a hospital with serious injuries, but his female passenger, also from Newark, died at the scene, police said. Authorities are withholding the victim's name until relatives are notified.

       The incident came as powerful storms swept through the region, part of a broader weather system that continues to threaten more than 30 million Americans along the I-95 corridor.

       The National Weather Service reported a weak tornado touched down near Omar, Delaware, on Monday afternoon, damaging only a small patch of trees.

       The dangerous weather pattern intensified early Tuesday when southeastern Pennsylvania declared a flash flood emergency after 4 to 6 inches of rain fell in 10 hours.

       Multiple water rescues were required in the Pennsylvania counties of Lancaster and Lebanon, particularly near Mount Joy and Manheim.

       The severe weather threat is ramping back up Tuesday, with damaging winds and flash flooding remaining the primary concerns.

       The threat zone spans from central Virginia to New York City, including major metropolitan areas like Washington, D.C., Baltimore, and Philadelphia.

       The storms are causing significant travel disruptions. As of 11:10 a.m. Tuesday, airlines canceled 623 flights nationwide, with more cancellations expected throughout the afternoon.

       Officials warn that ground stops and delays are likely at major airports along the I-95 corridor, particularly in Philadelphia, Washington, D.C., and New York.

       Delaware State Police continue to investigate Monday night's fatal crash and urge witnesses to contact the department or Delaware Crime Stoppers at 1-800-847-3333.

       For those affected by the tragedy, the Delaware State Police Victim Services Unit offers 24-hour support through their hotline: 1-800-VICTIM-1 (1-800-842-8461).