By Jim Melwert and Al Novack

PHILADELPHIA (CBS) –Chances are you heard the thunder overnight, as some heavy storms rolled through the region. Emergency personnel were kept busy as heavy rains caused some flash flooding in poor drainage areas. Fire and rescue were called out in the areas of Radnor, Upper Merion, and Conshocken. See the latest forecast from the CBS Philly Weather Center

Some problems lingered into the morning rush. The ramp from the southbound Blue Route to the Schuykill Expressway was closed because of standing water there.

Officials with Dow Chemical say it was lightning that sparked a three-alarm fire at the Rohm and Haas plant along state road in Bristol Township, near Croydon.

It started around 3:30am, two storage tanks holding about 200,000 gallons of ethyl acrylate and butyl acrylate, both chemicals used in paints. The company says any of the substance that escaped the tanks is contained in dikes and they say there’s no danger to any residents, but there is a very strong, eye-watering odor here, almost like onions.

“It’s my understanding the odors are not dangers,” Dow spokeswoman Barbara Del Duke says.

The fire went to three alarms, while it’s contained they say there have been some flare-ups. So crews putting foam on that fire.

A fire-police officer with more than 50 years of service as a volunteer suffered a heart attack while directing traffic near the fire and he later died. (See related story)

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