The entire state of Maine has been placed under a severe thunderstorm watch for Wednesday evening by the National Weather Service office in Gray.

The storms have the potential to produce heavy rains, frequent lightning, hail and damaging winds with enough force to knock down trees and power lines, said meteorologist Mike Cempa. Cempa said the severe thunderstorm warning will remain in effect through 10 p.m. Wednesday.

Cempa said the chief concern is that the storms could produce powerful winds reaching speeds up to 60 mph. That wind speed is about 14 mph less than hurricane-force winds.

Last week, most of the state was hit by a similar line of powerful thunderstorms that knocked out electrical power to most of the town of York. During that storm, trees fell on homes and cars in York. Emergency management officials also issued tornado warnings on July 15 – something that was not included in Wednesday’s warning.

“The wind profile is not set up for that (tornadoes),” Cempa said. “The big issue tonight will be high winds.”

Cempa said a line of slow-moving thunderstorms had reached northwestern Maine – the area near Farmington and Rumford and north of Millinocket – by mid-afternoon Wednesday.

Read Dave Epstein’s The Maine Forecast for an analysis of tonight’s storm.