The system will arrive from west to east early Thursday afternoon, Aug. 10, and continue to move through into the evening.
Heavy rain is expected to begin in the New York City area, Hudson Valley, and Capital regions, and western Connecticut around midday Thursday and later in the afternoon in Massachusetts and eastern Connecticut.
Areas where soaking rain is expected are shown in dark green in the first image above from AccuWeather.com.
About an inch of rainfall is now expected, with locally higher amounts of around 2 inches or more where there may be flooding, according to the National Weather Service.
The zone from New York City through Connecticut and into Boston will be at risk for flash flooding and severe storms Thursday afternoon and evening (shown in yellow in the second image above from AccuWeather.com).
"There is also an isolated damaging wind and isolated tornado/water spout threat across eastern Long Island and southeastern Connecticut," the National Weather Service said. "This could be expanded further north and west if a warm front sets up further north."
After Thursday's storms push through overnight, Friday, Aug. 11 will be sunny and pleasant, with a high temperature in the upper 70s to around 80 degrees.
The weekend should be mainly dry with mostly sunny skies on Saturday, Aug. 12, and Sunday, Aug. 13 with a high temperature in the mid-80s on both days.
There's a chance of afternoon and evening thunderstorms Saturday afternoon and evening in much of the region, with isolated tornadoes possible in eastern New England.
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