By Lauren Keiper

BOSTON (Reuters) - Flood watches and warnings from North Carolina into New England were triggered on Friday by widespread rainfall forecast on the first official day of fall and into the weekend.

Potentially heavy rain was expected to batter much of the region, including Philadelphia, New York, Boston and Washington.

Downpours expected this weekend together with rainfall forecast early next week could soak parts of the region with up to four inches of rain, more in some local spots, Weather Channel meteorologists said.

Some areas could see several inches of rain over a much shorter time, according to AccuWeather.com.

In North Carolina, there were reports on Friday of creek flooding in the Charlotte area, and some regions recorded two to three inches of rain in 60 to 90 minutes, said NWS Raleigh meteorologist Scott Sharp.

"You're pretty much getting a month's worth of rainfall in less than two hours," Sharp said.

Flood and flash flood watches and flood warnings were in effect from North Carolina northeastward into Massachusetts, according to the National Weather Service.

Many communities along the East Coast have barely had time to dry out from rains and flooding courtesy of Hurricane Irene and later, Tropical Storm Lee.

Historic flooding caused by the storms triggered the evacuation of hundreds of thousands of people and prompted President Barack Obama to declare emergencies in states from Vermont to Virginia.

Heavy rains were expected to hit North Carolina up into Maryland and Delaware through Friday night, according to AccuWeather.com.

The rainstorms were then forecast to drench the Mid-Atlantic into southern New England from later Friday into Saturday.

Rain was already falling steadily by mid-morning in eastern Pennsylvania, where the suburban Philadelphia area could see from one to three inches of rain through Saturday, according to NWS.

This soaking comes on the heels of more than 19 inches of rain in Philadelphia during August, a record for the wettest month in the city's history.

Rain was expected to be heaviest in New England and upstate New York through much of the day Saturday, AccuWeather.com said.

Residents in southern New England were likely to see up to two inches of rain later on Friday into Saturday with some higher totals in Connecticut, western Massachusetts and western Rhode Island, according to NWS.

(Additional reporting by Dave Warner in Philadelphia and Colleen Jenkins in Winston-Salem, North Carolina; Editing by Jerry Norton and Greg McCune)