Weather for New England and the Northeast

**Area Forecast Discussion, National Weather Service Boston/Norton MA,
226 PM EDT Sun Sep 13 2026**

**What Has Changed**

The heaviest rainfall has come to an end, with remaining showers tapering off from west to east through early this evening. Additional significant rainfall is not expected, although localized nuisance flooding may linger because 2 to 4 inches of rain fell across portions of Rhode Island and southeast Massachusetts today.

Small Craft Advisories have been issued for most waters from Monday afternoon through Monday night because of gusty winds.

**Key Messages**

1. The heaviest rainfall is ending, with drier conditions overnight, although low clouds and areas of fog are possible. A stray early morning shower remains possible.

2. Dry and fall-like weather is expected Monday into Tuesday, with a chilly start Tuesday morning.

3. High pressure will remain in control next week, bringing generally quiet weather. A brief period of summer warmth and humidity is expected Wednesday through Friday.

**Discussion**

**Key Message 1, Heaviest rainfall ending, drier overnight, though low clouds and areas of fog are possible**

The back edge of the heaviest rain is now moving from west to east across southern New England. Clouds are thinning across eastern New York and approaching western Massachusetts.

Rainfall totals have been impressive today, with many areas receiving 2 to 4 inches, especially across Rhode Island and southeast Massachusetts. The Flash Flood Watch remains in effect through 6 PM. Although the heaviest rain is over, light to moderate showers will linger and could still cause some nuisance flooding.

These showers should continue for the next couple of hours before ending between 4 PM and 6 PM. A few showers may linger an additional hour or so across the outer Cape.

Drier conditions arrive overnight, although low clouds and areas of fog may persist into early Monday morning. A final push of showers is possible around daybreak. Forecast guidance generally shows this activity weakening as it approaches southern New England, leaving only a spotty shower or two, mainly between 4 AM and 8 AM.

Some high-resolution forecast guidance suggests a slight increase in shower activity as it approaches the coast, possibly due to some instability near the shoreline. Even if this occurs, it is not expected to produce impactful weather and would be nothing like the rainfall seen today.

**Key Message 2, Dry and fall-like Monday into Tuesday, with a chilly start Tuesday morning**

Surface high pressure, meaning an area of sinking air that generally promotes fair weather, will build in from the Great Lakes region Monday. The high will settle overhead Monday night and remain in place through Tuesday, strengthening to around 30.42 inches of mercury. There is little significant weather expected during this period.

Some lingering moisture early Monday morning could produce areas of fog, but a much drier air mass will arrive by around noon. Precipitable water, or PWAT, which measures the amount of moisture available in the atmosphere, will fall below one-half inch.

Cold air advection, or CAA, meaning the movement of colder air into the region, will produce a period of breezy northwest winds Monday. Forecast soundings, which show the temperature and wind structure through the atmosphere, indicate a well-mixed layer extending upward to around 5,000 feet. This should allow some of the stronger winds higher in the atmosphere to mix down to the surface.

Winds several thousand feet above the ground are expected to reach 25 to 30 knots, resulting in surface wind gusts of roughly 20 to 30 mph from the north-northwest. High temperatures Monday afternoon will generally be in the lower to middle 70s.

With high pressure overhead Monday night, winds will become lighter near the surface. This will allow effective radiational cooling, meaning heat will escape efficiently from the ground under clear and calm conditions.

Forecast guidance supports some of the coldest temperatures of the season so far. Many locations could wake up Tuesday morning with temperatures in the 40s. It would not be surprising if towns in far northwestern Franklin County fall to around 38 to 40 degrees. Urban centers should remain milder, generally in the upper 40s to lower 50s. Boston may retain enough heat from the urban heat island effect to keep temperatures in the middle 50s.

Areas of ground fog are also possible Tuesday morning because of the abundant recent rainfall.

Tuesday will then be a crisp and dry day, with dew points mainly in the 50s and some upper 40s possible in northern Massachusetts. Dew point is a measure of the amount of moisture in the air, with lower values indicating drier conditions.

Temperatures around 3,000 feet above the ground are expected to be around 48 to 54 degrees, which supports afternoon high temperatures in the middle 60s to lower 70s. High pressure will slowly drift east during the day, with winds shifting toward the north-northeast.

**Key Message 3, High pressure in control next week brings generally quiet weather, with a brief return of summer warmth and humidity Wednesday through Friday**

High pressure will be firmly in control by Tuesday, bringing much drier weather to the region. Under dry northwest flow, dew points will be very comfortable to start the week, generally in the 40s.

Tuesday will offer a comfortable taste of fall, with high temperatures ranging from the upper 60s along the coast to the lower 70s inland.

As the high shifts over the Atlantic on Wednesday, winds will turn southerly. This will bring back more summer-like temperatures and increased humidity, with temperatures potentially returning to the upper 70s and dew points climbing into the middle 60s.

There remains some uncertainty regarding the forecast for late week and next weekend. The overall middle and upper atmosphere will feature a relatively west-to-east flow, while there is potential for a low pressure system to cross somewhere near southern New England.

Exactly where that system tracks remains uncertain. It could pass to our north or move closer to the region. Either way, the current forecast suggests a better chance for unsettled weather from late Thursday onward.