With the rain pouring down and streams rising, the National Weather Service has issued flood warnings throughout the state, asking people to take precautions and not to underestimate the power of rushing water.
As an expected 6 to 8 inches of rain falls, widespread river flooding is expected, the forecasters say.
They warned people not to try to drive across water-covered bridges or dips and they emphasized that people should never try to cross a flowing stream, even a small one, on foot.
"Do not underestimate the power of flood waters. Only a few inches of rapidly flowing water can quickly carry away your vehicle," the forecasters warned.
"We've had two 50-year storms in the course of 2-3 weeks. This is unheard-of. This is a little different, a little bit more dangerous due to the saturation from the previous storm. This could cause floodwaters to rise very, very fast," Governor Deval Patrick said at a news conference at a Department of Transportation depot in Lexington.
Peter Judge, spokesman for the Massachusetts Emergency Management Agency, said this morning that the area of greatest concern for river flooding is the Merrimack River valley, where the river itself and the tributaries that feed it have historically overflowed their banks. "The Merrimack Valley is an area we are watching very closely,'' he said.
Major flooding is expected to begin this afternoon or this evening on the Assabet River in Maynard, the Sudbury River in Framingham, the Charles River at Dover, the Blackston River, at Northbridge, the Neponset River at Norwood, the Nashua River in Pepperell, and the Blackstone River at Woonsocket, according to the weather service website. Other major streams, including rivers in the northern part of the state, are expected to see minor to moderate flooding.
John R. Ellement of the Globe staff contributed to this report.
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