Weather for New England and the Northeast

**Area Forecast Discussion, National Weather Service Gray ME**
**228 PM EDT Thursday,
September 24, 2026**

**KEY MESSAGES**

1. High pressure keeps dry conditions through Friday, but dangerous marine and surf conditions develop and persist through the weekend and possibly into Monday. In addition, splash-over is likely along the coast, with water levels approaching minor flood stage around the times of high tide.

2. A strong nor’easter will also bring widespread beneficial rain and gusty winds Friday night through the weekend.

3. Rain will gradually taper off at the beginning of the week, but conditions may remain unsettled at times through midweek.

**WHAT HAS CHANGED**

No significant changes were needed to the forecast at this time.

**DISCUSSION**

**Dry Friday, but increasing clouds and wind**

Strong high pressure and very dry air across northern New England will keep conditions dry through Friday. Moisture will begin increasing tonight and Friday as the nor’easter approaches southern New England from the south. For now, most of this moisture is expected to remain in the form of middle and high-level clouds, so precipitation is not expected during the day Friday.

The high clouds may keep tonight’s temperatures a little milder than the previous couple of nights, but temperatures across northern and interior areas could still fall into the lower to middle 30s, allowing some frost to develop. Valley fog is also likely again across northern valleys and the Connecticut River Valley.

Northeast winds will increase Friday, with gusts around 20 to 25 mph and possibly 25 to 35 mph closer to the coast.

**Dangerous marine and surf conditions**

Friday will also bring deteriorating marine and surf conditions that are expected to remain dangerous through the weekend and possibly into Monday. Seas will continue to build as swells arrive and a long, continuous fetch of northeast winds develops.

This will produce large breaking waves along the coast and a high risk of rip currents. The High Surf Advisory remains unchanged.

High astronomical tides will also increase this weekend. Increasing storm surge, potentially around 2 feet, could push water levels close to minor flood stage around high tide. Storm surge refers to the temporary rise in coastal water levels caused by a storm’s winds and pressure.

There is some concern that current storm surge guidance may underestimate water levels during a long-lasting period of northeast winds. Future forecasts could therefore be adjusted upward, which could require a Coastal Flood Advisory for portions of the coast.

**Rainfall**

As the low pressure system moves up the coast, it will be fighting against the dry high pressure system to the north. As a result, it may take some time for the atmosphere to become moist enough for precipitation to begin.

The ECMWF model continues to trend farther south, which would delay the onset of rain until mainly Saturday. The GFS and Canadian model solutions would bring rain into southern areas Friday night. If high pressure remains strong, the ECMWF solution remains possible even though it is currently an outlier. A farther-south storm track could keep some of the heavier rainfall bands south of the region.

Another complication is the possibility of thunderstorms or other convective elements. Forecast atmospheric profiles suggest there could be enough instability at times to produce embedded downpours. Convective activity refers to rising air that can produce heavier showers or thunderstorms within a larger area of rain.

The rainfall forecast remains one of the more uncertain parts of the nor’easter because it will depend heavily on the eventual storm track. The best chances for significant rainfall will be across southern New Hampshire and coastal and interior Maine. Forecast guidance indicates a 50 to 80 percent chance of at least 1 inch of rain and a 30 to 60 percent chance of at least 2 inches over a 48-hour period.

For these areas, a widespread 1 to 2 inches of rain appears reasonable, with locally higher amounts up to 4 inches possible. A farther-south storm track could result in lower rainfall totals.

**Strong northeast winds**

A tight pressure gradient will develop between unusually strong high pressure to our north and unusually strong low pressure to our south. A pressure gradient is the difference in atmospheric pressure over a given distance, and a tighter gradient generally produces stronger winds.

The NAM and GFS forecast soundings indicate winds in the 35 to 45 knot range near the top of the mixed layer, potentially beginning late Friday night and continuing through Sunday. The mixed layer is the portion of the atmosphere near the surface where stronger winds aloft can mix downward.

As a result, Wind Advisory criteria gusts of up to 45 mph could occur at times along the coast and into interior areas during this period.

**Unsettled conditions continue into early next week**

The upper-level low will stall and move out of the region slowly, keeping precipitation chances in the forecast Monday and possibly Tuesday.

Global forecast models are beginning to show better agreement that another round of locally heavy rainfall could occur Sunday night into Monday as the upper low meanders north-northeastward along the coast. Forecast trends will need to be monitored because models can have difficulty resolving this type of slow-moving, low-predictability weather pattern.

A progressive ridge, meaning an area of higher pressure aloft, will cross the region sometime during the middle of next week. This will be followed by a quick-moving wave and frontal system.

Temperatures may also trend warmer by midweek, with widespread lower 70s returning to the forecast by Wednesday or Thursday.