Weather for New England and the Northeast

**Area Forecast Discussion, National Weather Service Gray ME, 243 PM EDT
Wed Aug 19 2026**

**WHAT HAS CHANGED**

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

**KEY MESSAGES**

1. Mostly dry weather with seasonable temperatures continues into Thursday, although some uncertainty remains over whether southern New Hampshire and southwestern Maine will see more light showers later Thursday. Fog could also become locally dense across portions of western Maine through tonight.

2. The weather turns cooler through the weekend, with the potential for a system to bring rain late in the week. Temperatures trend warmer during the first part of next week, while the overall weather pattern remains somewhat unsettled.

**DISCUSSION**

**KEY MESSAGE 1 DESCRIPTION**

A slow-moving front is located near the eastern Great Lakes and St Lawrence River Valley this afternoon. A 500 mb shortwave, an area of lower pressure higher in the atmosphere, will interact with this front and produce isolated to scattered showers, mainly around the mountains this afternoon and evening. Elsewhere, partly sunny conditions will continue, with afternoon temperatures in the mid 70s to low 80s.

An area of marine fog and low clouds is also being monitored on satellite imagery. This could bring reduced visibility along the Maine coastline as early as this afternoon before spreading inland this evening and tonight. The greatest concern is along and east of the I-95 corridor from Portland to Augusta and Waterville, where fog could become locally dense. Patchy fog could also develop in many other areas tonight, especially in and around river valleys. Overnight lows will range from the 50s to lower 60s.

Fog should lift by mid-morning Thursday, followed by another seasonable day with highs in the mid 70s to lower 80s. The previously mentioned front will move into New England. While most areas should remain dry, a few showers could develop Thursday afternoon and evening as clouds increase.

The better chance for showers will be across southern New Hampshire and perhaps far southwestern Maine as a more defined wave moves across southern New England. Recent HRRR model runs have trended toward this possibility, while other models keep most of the precipitation farther south. For now, precipitation chances are 20 to 30 percent in this area, but those chances could be adjusted higher or lower as model trends become clearer. Either way, rainfall amounts are expected to be light, with a tenth of an inch or less.

If showers develop, they should end by or shortly after midnight Thursday night. More valley fog will be possible overnight, with lows a little cooler than tonight. Most locations will be in the 50s, with some northern valleys dropping into the 40s.

**KEY MESSAGE 2 DESCRIPTION**

A shortwave ridge, an area of somewhat higher pressure aloft, builds in Friday behind the departing trough. High pressure is expected to move into the region and dominate the weather.

Friday temperatures will generally remain in the mid to upper 70s, with a few locations in southern New Hampshire approaching 80 degrees. A seabreeze should develop during the afternoon, bringing cooler temperatures near the coastline by early evening. Overnight temperatures should remain in the mid to upper 50s.

Looking ahead to the weekend, forecast models continue to disagree on when the first batch of precipitation will reach the area Saturday. A 500 mb low, or an area of lower pressure in the middle levels of the atmosphere, will move east from the west and interact with moisture approaching from the south.

Some forecast models remain uncertain about the position of this trough and its associated moisture. The Canadian and European models bring precipitation into southern portions of the forecast area by Saturday afternoon, while the GFS keeps most widespread precipitation farther south.

Because of this disagreement, it is still too early to determine whether Saturday will be mainly dry or wet. Forecast trends will be monitored over the coming days. For now, precipitation chances are generally 20 to 40 percent across portions of the forecast area by late Saturday. High temperatures should be in the upper 60s to low 70s.

Rain chances could increase further Saturday night into Sunday as the 500 mb trough moves across much of the Eastern Seaboard. Ensemble forecast guidance, which uses many model simulations to identify the most likely outcomes, shows a strong signal for measurable rainfall across the area.

Current guidance suggests more than a quarter of an inch of rain could fall across much of the forecast area, with the potential for heavier amounts along the immediate coastline and at higher elevations.

The trough currently appears likely to remain an open wave, meaning it will continue moving east rather than becoming a closed area of low pressure. However, this could change. If the trough closes off, the arrival and departure of the precipitation would likely be slower, potentially allowing rain to continue into early next week.

By Sunday night, rain could begin clearing from the coastline, although upslope showers could continue into early Monday morning, particularly across higher elevations.

Drying conditions should generally take over during early next week, although some forecast models continue to show chances for upslope showers into the middle of the week. Those shower chances should decrease as the week progresses, with some models showing nearly zero rain probabilities as early as Tuesday as high pressure returns.

Temperatures next week should be close to average for this time of year, with highs in the mid to upper 70s and overnight lows in the mid 50s to low 60s.