The system, sparked by a slow-moving cold front, is on track for Sunday afternoon, July 9 into Sunday evening, according to the National Weather Service.
Between 2 and 4 inches of rainfall is expected in areas shown in green in the first image above from AccuWeather.com. Locally higher are possible, especially in areas in darker green.
Widespread flood watches have been issued throughout much of the Northeast. Areas most at risk for flash flooding can be seen by clicking on the second image above.
"Showers and thunderstorms are expected to develop today and will be capable of producing heavy downpours," the National Weather Service said in a Hazardous Weather Outlook statement issued Sunday morning. "This may result in flooding of urban, low-lying or poor drainage areas, and small streams and creeks.
There should be scattered showers in the morning before showers, and storms become likely starting early in the afternoon into the night as the system barrels through.
"The rain from Sunday night can result in significant travel delays for the Monday morning drive, especially if there are road closures due to high water," AccuWeather Meteorologist Alex DaSilva said.
Sunday's high temperature will generally be around 80 degrees.
The storm will linger into Monday, July 10 with showers likely and scattered storms possible at any point during the day and night, the National Weather Service says. The high temperature will be around 80 degrees.
Farther east, including in Boston, downpours are expected to be most intense from later Monday, perhaps for the commute home, to early Tuesday morning, July 11, according to AccuWeather.com.
Skies will gradually become mostly sunny from west to east on Tuesday, July 11 with a high temperature in the mid-80s.
The mercury will climb to a high of around 90 degrees on Wednesday, July 12 with plenty of sunshine.
Unsettled weather could return starting on Thursday, July 13 with chances of new rounds of showers and thunderstorms possible and lasting into next weekend. But skies are expected to be partly sunny for most of each of those days.
Check back to Daily Voice for updates.
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