503
FXUS61 KGYX 192307
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
707 PM EDT Wed Aug 19 2026

.WHAT HAS CHANGED...
No significant changes made to the going forecast this evening.

&&

.KEY MESSAGES...
1. Mostly dry weather with seasonable temperatures continues
into Thursday, although some uncertainty remains if southern NH
and SW Maine will see more in the way of light showers later in
the day on Thursday. Fog could also be locally dense across
portions of western ME through tonight.

2. The weather trends cooler through the weekend with the
potential for a system to bring rain, late in the week. Temperatures
trends back warmer for the first part of next week with the overall
pattern remaining somewhat unsettled.

&&

.DISCUSSION...
KEY MESSAGE 1 DESCRIPTION...
A slow-moving front is situated in the vicinity of the eastern Great
Lakes and St Lawrence River Valley this afternoon. Aloft, a 500mb
shortwave will intersect this front and result in the development of
isolated to scattered showers, mainly in and around the mountains
this afternoon and evening. Elsewhere, partly sunny conditions
prevail with afternoon temps in the mid 70s to low 80s.

Also keeping an eye on an area of marine fog and stratus on latest
satellite imagery. This could bring reduced visibilities as early
as this afternoon along the Maine coastline before potentially
spreading inland this evening and tonight, especially along and
east of the I-95 corridor from Portland to Augusta and
Waterville, where fog could be locally dense. Aside from this
area, patchy fog could develop in many areas tonight, especially
within and near river valleys. Overnight lows will range from
the 50s to lower 60s.

Fog will lift by mid-morning Thursday, and another seasonable day is
expected temperature-wise with highs in the mid 70s to lower 80s.
The previously mentioned front will push into New England, and while
most will stay dry, a few showers may develop during the afternoon
and evening while clouds increase across the area. A somewhat better
chance of showers will be across southern NH and perhaps far SW
Maine as a more-defined wave moves across southern New England. The
last couple runs of the HRRR have trended toward this while other
models keep the precip more suppressed to the south. For now PoPs
are 20-30% in this area, but may need to be raised or lowered with
how model trends go. Either way, amounts are expected to be
light and a tenth of an inch or less.

If the showers materialize, they should end by or shortly after
midnight Thursday night. More valley fog possible overnight, and
lows will be a tad cooler than tonight with most 50s, except 40s in
some of the northern valleys.

KEY MESSAGE 2 DESCRIPTION...
Shortwave ridging builds in Friday behind the departing trough
with high pressure looking to move in and dominate in our
forecast area. For Friday, temperatures will generally hold in
the mid to upper 70s, with a few places in Southern New
Hampshire flirting with the 80 degree mark. Once again, as for
most of the summer, a seabreeze should kick in during the
afternoon, dropping temperatures near the coastline a few
degrees come time early evening. Overnight temperatures should
stick to the mid to upper 50s as well. Looking ahead to the
weekend, models are mixed on when the first batch of
precipitation moves into our area for Saturday. Here, a 500 mb
low from our west joins up with approaching moisture from our
south. Some deterministic models, are a bit unsure of the
positioning of this trough and its associated moisture with
long- range solutions like the Canadian and European bring
precipitation into southern areas of our CWA by Saturday
afternoon, while the GFS holds back on widespread precip
overall. Knowing this, it would be better to see some agreement
in the models regarding precip because, as of right now, it is
too early to tell when this potential batch of precipitation
moves in, but trends will be monitored in the coming days to
figure out whether Saturday will be dry or wet. At the moment,
PoPs are generally in the 20-40% range over our portions of our
CWA by late in the day on Saturday. In terms of temperatures,
highs will be in the upper 60s to low 70s.

As stated above, rain chances could further increase Saturday
night into Sunday as the 500mb works its way in and covers most
of the Eastern Seaboard. A strong signal from ensembles shows
our area seeing measurable rain with models hinting at greater
than a quarter of an inch for most of our CWA, with the
potential for heavier amounts of rainfall along the immediate
coastline and at higher elevations. At the moment, this 500 mb
trough looks to remain an open wave, but this could change if it
closes off, to which a slower onset and end of precipitation
will likely be the result. If the trough closes off, the slower
onset and end could come to fruition, where in this case,
precipitation could have trouble ending by the start of next
week. Overnight Sunday, rain could be clearing out away from the
coastline, but upslope showers could continue through early
Monday morning.

Drying conditions should generally dominate going into early
next week, with long range models still hinting at chances for
upslope showers continuing into the middle of next week. These
upslope shower chances will wane as the week progresses, with
some models showing near zero rain probabilities as early as
Tuesday, along with high pressure returning to our area. On the
temperature side starting next week, highs look to be average
for this time of year staying in the mid to upper 70s with
nightly lows in the mid 50s to low 60s.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Through 18Z Thursday...Mainly VFR, but an area of marine
fog/stratus brings IFR or LIFR to RKD through tonight. For
tonight, the marine fog could bring IFR or lower conditions to
PWM and AUG but is of lower confidence. Elsewhere (especially
LEB and HIE), valley fog could bring IFR or lower late tonight
into early Thursday. Conditions should improve to VFR by 14Z
Thursday.

Outlook:

Rest of Thursday: Mostly VFR, except MVFR possible due to -SHRA at
MHT, CON and PSM, mainly after 20Z.

Thursday night: -SHRA and MVFR remain possible across southern NH
through around 06Z. Valley fog could then bring IFR or lower
restrictions for LEB and HIE.

Friday-Saturday night: Generally VFR during the day with fog
possible at night. Some brief MVFR restrictions are possible at
coastal terminals Saturday if showers materialize.

Sunday-Sunday night: Generally MVFR conditions with widespread
rain expected. Rain may taper off Sunday night giving way to
areas of fog that would likely bring about IFR conditions.

Monday: Conditions return to VFR, but there may still be some
MVFR and/or IFR conditions early.

&&

.MARINE...
Through Thursday night...SCA conditions are not expected. Winds
briefly turn west to northwest tonight, but remaining light, as weak
boundary moves into the waters. Winds return to more southerly
Thursday as a weak front approaches, and these will switch to
north/northwest Thursday night behind the front. Fog will also
remain possible at times, especially from around Portland
eastward.

Generally sub-SCA conditions are expected to prevail late week
into early next week, but there is potential for a coastal
system to bring some brief SCA conditions over the weekend.
Areas of fog are also likely through much of this period.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$

DISCUSSION...Baron/Combs/Ekster
AVIATION...
MARINE...