Weather for New England and the Northeast

**Area Forecast Discussion, National Weather Service Gray ME, 636 AM EDT
Sun Aug 16 2026**

**WHAT HAS CHANGED**

No major changes were needed for this update.

**KEY MESSAGES**

1. High pressure maintains dry weather today.

2. Rain accompanies a passing system tonight into Monday morning. A period of moderate to heavy rainfall after midnight and early Monday morning could result in nuisance flooding or ponding in poor drainage areas for the morning commute.

3. A fairly tranquil week beyond Monday with near-seasonable temperatures. Slightly warmer and wetter conditions may be present midweek.

**DISCUSSION**

**KEY MESSAGE 1 DESCRIPTION**

Similar to last night and yesterday morning, valley fog could be locally dense in some areas along the Connecticut River, but the fog should lift by 8 to 9 AM.

For the rest of the day, low pressure crossing through the Great Lakes will shift the high pressure currently overhead to the east. Clouds will increase through the day, mostly high and middle-level clouds, as moisture increases. However, the air mass will remain too dry for rain during the daylight hours.

High temperatures will mostly be in the 70s, with readings closer to 80 degrees in parts of southern New Hampshire.

**KEY MESSAGE 2 DESCRIPTION**
Clouds will lower and thicken this evening as a low pressure system tracks along the Canadian border and draws more moisture northward from the south. Latest guidance indicates showers moving into New Hampshire this evening, followed by more widespread showers and an area of steady rainfall spreading from west to east overnight and into Monday morning.

Rainfall rates could become efficient at times late tonight and Monday morning. PWATs, or precipitable water values, are expected to increase to 1.50 to 1.80 inches across much of the area. This means there will be an unusually large amount of moisture available for rainfall. Increasing depth of warmer clouds and stronger upward motion could contribute to ponding on roadways during the morning commute.

After Monday morning, lingering low-level moisture and weak upward motion will remain in place through much of the day. Skies should stay mostly cloudy, with occasional light rain and drizzle possible.

There is good agreement in the latest guidance that the area of higher rainfall totals may shift slightly farther north, while amounts across southern areas have generally trended downward.

Northern areas are forecast to receive mostly 0.50 to 0.75 inches of precipitation, although a stripe of higher amounts, around 1.00 to 1.50 inches, is possible somewhere across northern New Hampshire and into the western Maine mountains.

Southern New Hampshire and southwest Maine could generally receive less than 0.25 inches, although individual showers could produce locally higher amounts.

**KEY MESSAGE 3 DESCRIPTION**
Forecast guidance remains mixed for Tuesday. Global forecast models keep a disturbance just offshore, while newer high-resolution guidance suggests a drier day as the disturbance moves away more quickly.

One thing that does appear consistent is elevated humidity, with dew points in the 60s. Some global guidance shows a signal for afternoon showers or thunderstorms, but confidence is low because moisture may be shallow and sinking air could limit storm development.

Wednesday currently appears to be the warmest day of the week, with widespread temperatures in the 80s likely as winds turn southwest. A trough, an elongated area of lower pressure and cooler air aloft, will move into the region late Wednesday and bring another chance for precipitation.

There will be stronger upward motion and some favorable upper-level jet stream dynamics. However, because the main part of the trough will remain near Hudson Bay, its influence on New England should be limited. As a result, rain chances are expected to remain scattered rather than widespread.

**LATE WEEK**

Forecast guidance begins to diverge by late week. There are generally two possibilities, with one scenario keeping the trough around longer and another allowing it to move away quickly as high pressure returns. This will determine how dry the region becomes late in the week.

What does appear more consistent is a drop in upper-level heights and temperatures about 5,000 feet above the surface, suggesting temperatures will trend somewhat cooler.
Even so, temperatures are not expected to be unusually cold or otherwise abnormal for this time of year.