Tornado warning startles a sleeping Philadelphia. What did you do?

Thousands of Philadelphia-area residents were startled from their sleep early Monday when cell phone alarms went off to report a tornado warning had been issued.

“Take shelter now,” said the alert timed at 3:21 a.m. In a separate text, the Philadelphia Office of Emergency Management told recipients: “Take shelter ASAP in a basement or interior room with few or no windows.”

While some area residents heeded the warning and took shelter, others ignored the middle-of-the-night message, or didn’t hear it at all. Some who were jolted awake turned to social media to express their surprise or annoyance.

No tornadoes were ultimately reported in the immediate Philadelphia area, but the line of storms that prompted the warning knocked down trees and power lines, damaging cars and homes and triggering outages for thousands of utility customers around the region.

The National Weather Service in the meantime said it was looking into possible tornadoes in the bordering towns of West Windsor and Cranbury in Central New Jersey.

The weather service confirmed a tornado touched down in Laurel, Sussex County, Delaware. The EF-2 tornado — a “strong” tornado on the Enhanced Fujita Scale — had a maximum wind speed of 120 mph, officials said.

The tornado destroyed a barn, and a tree fell on a house, leading to one injury, the weather service said. Roof and tree damage was also reported.

And the weather service in State College, Pa., said a tornado touched down near Buffalo Valley in East Buffalo Township, Union County, damaging a church, destroying a barn, and uprooting trees. The service said the twister was also an EF-1 packing winds of 86 to 110 mph and capable of causing moderate damage.

In Delaware, pictures posted by the Laurel Fire Department showed major damage to a number of buildings, including an Utz snack food warehouse where a section of the roof was torn off.

The alert came as a line of thunderstorms packing heavy downpours and gusting winds advanced on the region. Tornado warnings also were sent out in parts of Delaware while areas not covered by a tornado warning received alerts for severe thunderstorms.

The tornado warnings came after strong storms killed eight people in the South over the weekend.

The weather service said wind gusts of 60 mph or more were reported around the area, including 63 mph at Philadelphia International Airport, during the brunt of the storm.

About 500 lightning strikes were reported as the storm moved through the Philadelphia area, 6ABC reported. An advisory is in effect until 10 p.m. for high winds, with potential gusts of up to 50 mph.

Peco reported that most power outages from the storm affected customers in Delaware County and Philadelphia. By afternoon, there were about 5,600 lingering outages around South Jersey and Southeast Pennsylvania.

Besides damage caused by downed trees, 20 families were displaced in Camden when part of the roof of their apartment building blew off. No serious injuries have been reported.

The weather service issued the tornado warnings as part of FEMA’s nationwide Integrated Public Alert Warning System. Your cell phone must be set to receive the alerts. You also can sign up for alerts from the Philadelphia Office of Emergency Management on the agency’s website.

Staff writer Anthony R. Wood contributed to this article.

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