Weather for New England and the Northeast

Area Forecast Discussion, National Weather Service Boston/Norton MA

702 AM EDT Tuesday, October 20, 2026

What Has Changed

Confidence continues to increase that a noreaster will remain offshore. While impacts on land will be minimal, hazardous conditions are expected for boaters and the marine community because of large waves and gale force winds.

Key Messages

A noreaster passes offshore late Wednesday into Thursday, bringing a few showers to areas east of Interstate 95. Otherwise, dry and breezy conditions prevail through the middle of the week.

Fairly cool weather arrives Friday with only a very low chance of an early morning shower. Temperatures gradually moderate while dry weather returns for the weekend and early next week.

## Discussion

### Key Message 1, Offshore Noreaster Brings Wind More Than Rain

No significant changes were made to the near and short term forecast overnight.

A strong high pressure system, around 30.4 inches of mercury, positioned northwest of Southern New England will provide another dry day across the region. Expect more filtered sunshine across eastern areas today, while western locations enjoy mostly clear skies.

Temperatures about 2,500 feet above the ground are expected to range from 46 to 50 degrees, helping afternoon highs climb into the lower to middle 60s inland. Coastal communities will stay a little cooler, mainly in the upper 50s to lower 60s.

Winds become a bigger factor today as the pressure difference between the high pressure system and the developing noreaster off the North Carolina coast increases. Northeast wind gusts of 20 to 30 mph are expected east of Interstate 95, while the strongest gusts of 30 to 40 mph are most likely along the east facing Massachusetts coastline, Cape Cod, and the Islands. Earlier forecasts suggested gusts above 45 mph on Nantucket, but confidence in those stronger winds has decreased as the latest forecast models favor a track farther offshore.

Those breezy conditions continue through tonight and into Wednesday as the storm strengthens while moving northeast. Rain remains limited during this period, but cloud cover gradually increases overnight into Wednesday. Those clouds will help keep temperatures milder, with Cape Cod and the Islands staying in the upper 40s to lower 50s, while inland communities cool into the upper 30s and lower 40s before clouds thicken later in the night.

Wednesday stays mostly dry, although temperatures run a little cooler because of the increased cloud cover. Wind conditions will be very similar to today.

Forecasters are also using Convective Allowing Models, or CAMs, which are high resolution forecast models that help pinpoint where showers may develop. Those models indicate a low chance for a few showers after 2 PM EDT Wednesday, mainly across Nantucket, Marthas Vineyard, outer Cape Cod, and Chatham.

Confidence remains high that this slow moving noreaster will stay offshore, limiting meaningful impacts across most land areas. Forecast models, including the NAM, GFS, and ECMWF, which are major weather prediction models used to compare possible storm tracks, continue trending toward an offshore solution. The latest Monday evening model run moved closer to the GFS forecast, while the ECMWF remains a bit farther offshore. Large groups of forecast model simulations, called ensembles, continue supporting the storm making its closest approach late Wednesday night into early Thursday before accelerating into the North Atlantic.

Most communities remain dry, with the best chance for showers confined to Cape Cod and the Islands from Wednesday afternoon through early Thursday morning. A few showers may brush eastern Massachusetts and Rhode Island, but rainfall is expected to remain light.

The marine story is much different. Waves of 7 to 13 feet are expected offshore, accompanied by gale force north northeast to northeast winds. Even though astronomical tides are relatively low, the prolonged wind and wave action could still lead to beach erosion.

### Key Message 2, Cool Friday Followed by a Better Weekend

As the noreaster pulls away, strong high pressure settles over the region for the weekend.

One feature worth watching is a mid level cold pool, an area of unusually cold air several thousand feet above the ground, moving through early Friday with a robust northern stream shortwave, which is a fast moving disturbance in the upper atmosphere. Moisture levels, measured as precipitable water, will be fairly limited by then, so only a slight chance of a spot shower exists early Friday morning, mainly east of Interstate 95.

Otherwise, high pressure encourages sinking air, which helps keep conditions quiet through the weekend and into Monday.

Friday looks like the coolest day, with highs mainly in the lower 50s. Saturday morning could bring frost to some areas if winds become light enough, with lows ranging from the upper 20s to the middle 30s.

From Saturday through Monday, temperatures gradually climb a few degrees each day as warm air advection, meaning warmer air moving into the region, develops overhead, allowing the warming trend to continue into early next week.