A flash flood watch is posted from Bar Harbor to Bangor to Houlton through 2 p.m. Saturday as the first storm of the hurricane season sweeps across Maine and the Maritimes.

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The National Weather Service says Arthur has now weakened to a tropical storm, with sustained winds of 70 mph. As of 7:00 am, it was centered about 50 miles southwest of Nova Scotia, moving northeast at about 22 mph.

Forecasters expect  as much as 5 inches of rain in Down East Maine with rainfall rates of 1-2 inches per hour in some places.  This will lead to rapid rises of small streams and possible flooding in areas with poor drainage.

Fierce winds with gusts up to 55 mph were causing power outages Saturday morning. As of 8:00 am, Emera Maine was reporting more than 4,000 customers without power in Hancock, Penobscot and Washington counties.

The National Weather Service says conditions will improve through the afternoon and evening as the storm moves away from Maine.