Heavy Rain Across Southern New England Today and Tonight
Lingering Bands of At Least Light to Moderate Rain Thursday/Thursday Night
Bands of heavy rain were moving into southern New England this morning. This is the start of a fairly long duration of periods of heavy rain. Some of the heavier bands today and tonight could contain rainfall rates of 1 to 2 inches per hour.
An anomalous closed upper-level low pressure area will move very slowly east across our region the next couple of days thanks to blocking high pressure over the North Atlantic. A surface low pressure area will move slowly west to east just off the south coast of New England. Associated heavy rain over eastern New York (including the Albany area, Catskills, and New York City) will pivot across CT, northwest RI, and western and central MA today. Heavy rain bands will persist into tonight across central and western portions of southern New England. Heavy rain bands will become more numerous across eastern MA this afternoon and persist through tonight.
This strong upper low pressure trough for this time of year will result in upper-level diffluence (i.e., air spreading apart or diverging at upper levels) which in turn promotes deep and vigorous uplift of very moist air in place. In addition, southeast and then more easterly winds associated with low level low pressure will lead to low level convergence (which also induces strong uplift of very moist air) as well as orographic uplift across the higher terrain of the Berkshires, Worcester Hills, and to some extent across CT and northwest RI. The heaviest rain will likely fall across the Berkshires, Worcester Hills, and portions of northern CT and northwest RI.
This low pressure system will start to gradually weaken Thursday and Thursday night and finally move offshore on Friday. Light to moderate bands (with perhaps still even a few heavy bands) of rain may pivot across central MA and RI on Thursday and across eastern MA Thursday and Thursday night.
Projected total rainfall totals: A general 3 to 5 inches of rain with locally higher amounts to 6+ inches will likely fall across the Berkshires. As much as 2 to 4 inches with locally higher amounts of 5+ inches will likely fall across central MA (highest over the Worcester Hills), CT, and northwest RI. Across the rest of RI and eastern MA, generally 1 to 3 inches of total rainfall are expected with possibly localized higher amounts to 4 inches.
Flood potential: The National Weather Service has a Flood Watch in place for western and central portions of southern New England where a risk of small stream and urban flash flooding exists for today and tonight. Across eastern portions of southern New England, street flooding is likely this afternoon and tonight, especially in urban areas. Significant rises are expected along area rivers, but at this time the larger rivers themselves are expected to remain within their banks.
Coast/Marine: Along the coast, gusty southeast and then easterly winds will cause rough seas. Small craft would be advised to remain in port through at least Thursday. Although there will be fairly high surf, the astronomical tides are not all that high, and coastal flooding is unlikely.
Next Message
Will update this weather blog with any significant changes to the forecast. Otherwise, the next message will be the weekly significant weather outlook scheduled for Monday August 3.
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Message issued July 29, 2026 by:
Bob Thompson
Retired National Weather Service Meteorologist
Blue Hill Observatory and Science Center Board member
