A line of fast-moving thunderstorms blew through Maine on Thursday afternoon and evening, knocking down trees, flooding some streets in Portland, causing power outages and contributing to a rush hour traffic accident on Interstate 295 in Falmouth that snarled traffic for miles.

The Waterboro Fire Department said a fire that destroyed a barn at 259 Townhouse Road may have been caused by a lightning strike. The fire was reported just after 5 p.m.

Bob Marine, a meteorologist with the National Weather Service in Gray, said storms started building late Thursday morning in New Hampshire before moving into western and southern parts of Maine in the afternoon. High winds accompanying the storm downed trees and knocked out power, and “there was a lot of lightning,” he said.

More than 6,000 Central Maine Power Co. customers and more than 13,000 Emera Maine customers lost power Thursday evening during the storm. Bob Potts, an Emera spokesman, said the outages were caused by high winds and lightning.

Potts said Mount Desert Island experienced the most outages among Emera customers.

Marine said about half an inch of rain fell in Portland and it was sorely needed. Only 1.46 inches of rain has fallen in Portland this month. The city averages 3.62 inches.

The rain came down so hard and fast that it caused some local flooding, including on Commercial Street in Portland.

State Trooper Marvin Hinkley said traffic was slowing on Interstate 295 southbound in Falmouth just after 5 p.m. during heavy rain when a car driven by 22-year-old Elizabeth Morgan of New Gloucester was rear-ended by a 2003 Peterbilt tractor-trailer truck driven by Paul Bean, 53, of Levant.

Hinkley said traffic was at a standstill for several miles following the accident.

“People are out of their cars and walking around. I even saw two people throwing a Frisbee near mile 14,” Hinkley wrote in an email.

No one was injured but traffic was restricted to one lane. Traffic on the northbound side of the highway was also delayed by the crash.

Bean is not expected to be charged, Hinkley said.

Hinkley said the truck was removed and both lanes of the highway were reopened to traffic around 7:30 p.m.

Marine said Friday should turn into a pleasant day with some sun and far less humidity.

Only subscribers are eligible to post comments. Please subscribe or to participate in the conversation. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.