Weather for New England and the Northeast

**Area Forecast Discussion, National Weather Service Boston/Norton MA**
**353 AM EDT Wednesday, July 22, 2026**

**What Has Changed**

Small Craft Advisories have been extended through tonight across the northern coastal waters and through Thursday across the southern coastal waters.

**Key Messages**

* Warmer and drier for the most part today with the chance for isolated showers and thunderstorms in the afternoon.

* Mainly dry with seasonable temperatures Thursday through the weekend.

**Discussion**

**Key Message 1, Warmer and drier for the most part today with the chance for isolated showers and thunderstorms in the afternoon.**

The widespread showers and thunderstorms that affected southern New England overnight have moved away early this morning. However, another area of showers will move across the south coast, far southeastern Massachusetts, Cape Cod, and the Islands after about 4 AM, continuing into the early morning. Elsewhere, dry conditions are expected.

High humidity and recent rainfall have allowed areas of patchy fog to develop this morning. Conditions will gradually improve through the morning as sunshine breaks out from west to east. Afternoon temperatures will climb into the lower to middle 80s.

There remains a risk for isolated showers and thunderstorms this afternoon as a cold front approaches from the west. Ahead of the front, more humid air will move into the region. Combined with daytime heating, this will create an increasingly unstable atmosphere. Forecast values of Surface Based Convective Available Potential Energy, or SBCAPE, between 1000 and 1800 joules per kilogram indicate enough energy for thunderstorms to develop.

Forecast models continue to show enough clearing during the day to support thunderstorm development. The combination of moisture and atmospheric instability should allow scattered showers and thunderstorms to form as the cold front moves east.

Forecast wind shear, the change in wind speed and direction with height, will range from 30 to 40 knots through the lowest 6 kilometers of the atmosphere. This is favorable for thunderstorms to organize and could allow one or two storms to become strong or severe.

Forecast soundings, which are atmospheric profiles produced by weather models, indicate plenty of moisture near the ground but drier air in the middle levels of the atmosphere. That dry air could limit the overall number of storms that develop. High resolution convection allowing models, known as CAMs, continue to suggest only isolated thunderstorm coverage, meaning most locations will remain dry.

Any storm that does develop could produce locally damaging wind gusts. Showers and thunderstorms are most likely from mid to late afternoon, moving from west to east before ending offshore early tonight.

The cold front will move through tonight, shifting winds to the northwest and bringing in cooler, less humid air.

**Key Message 2, Mainly dry with seasonable temperatures Thursday through the weekend.**

The cold front will move offshore by Thursday while an upper level trough, an elongated area of lower pressure in the atmosphere, crosses the Northeast. High pressure will gradually build eastward, supporting several days of mainly dry weather.

Temperatures about 2,500 feet above the ground, known as the 925 millibar level, are forecast to range from about 61 to 68 degrees. This supports afternoon highs in the lower to middle 80s through the weekend.

Forecast ensemble guidance, which combines many model simulations to measure forecast confidence, continues to favor dry weather through the weekend. A more unsettled weather pattern, with increasing chances for precipitation, is expected to develop early next week.