786
FXUS61 KGYX 101802
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
202 PM EDT Sun Aug 10 2025

.SYNOPSIS...
High pressure is in control for the next several days.
Temperatures continue to rise through the first half of this
week as a ridge of high pressure builds over the Northeast. The
ridge starts to break down mid week and that will allow for
some chances of showers and thunderstorms as a cold front
approaches.

&&

.NEAR TERM /THROUGH TONIGHT/...
Impacts and Key Messages:
* No significant weather impacts expected

A diurnal cumulus field is present over the mountains again
this afternoon, with a few isolated and short lived showers
developing within it. As has been the case with the the last
couple days, this activity should fizzle out heading through the
evening. Otherwise, the first of what is expected to be a few
days of hot temperatures is nearly in the books with many
locations near or at 90 at the time of this writing.

Contrary to what we saw with recent heat events we will
continue to have pleasant overnight temperatures that bring
about some relief from the heat of the day. Mostly clear skies
and light winds should allow for radiational cooling again
tonight and a MAV/NBM blend has been working out well to handle
that. Expect low temperatures in the low to mid 60s south of the
mountains, and upper 50s to low 60s to the north. Fog will
persist in the valleys and midcoast, with the latest HREF
suggesting some of the coastal fog could be locally dense.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
Impacts and Key Messages:
* Heat indices and/or actual temperatures will approach 95F in
  many inland locations tomorrow. A Heat Advisory has been
  issued for areas where confidence is highest in achieving a
  few hours of heat indices around 95F.

The ridge axis becomes centered overhead Monday, with the
center of surface high pressure well offshore. 850mb temps climb
into the +18 to +20 range equating to high temperatures around
90 areawide and near 95 in some southern inland locations. A
seabreeze likely develops for the coast and stunts the heat a
bit, but temperatures in the mid to upper 80s are still possible
right to the water. The fortunate aspect with this round of
heat is that it is looking drier compared to the oppressive
dewpoints we say with events last month. However, there is still
high confidence that at least a portion of the area should be
able to achieve a few hours of heat index values around 95F, so
a Heat Advisory has been issued accordingly. This is looking
like it is going to end up being the longest stretch of heat we
have seen so far this summer, with many locations seeing some
90s beginning today (Sunday) (see the long term section below
for more information on when we may see relief). We remain in a
pattern where isolated afternoon showers are possible in the
mountains.

Clear skies and light winds will continue for another night, so
knocked backed nighttime temperatures with MAV guidance. This
results in another pleasant night with low temperatures in the
low to mid 60s to help alleviate some heat stress. The Heat
Advisory will run through the night as it won`t be a complete
relief and some heat stress will remain accumulated before we go
right back into it on Tuesday. Expect another night with valley
fog and some coastal fog, mainly on the Midcoast.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Key Messages:
* Heat continues Tuesday and Wednesday with highs in the upper
  80s to mid 90s. A Heat Advisory continues into Tuesday for
  mostly interior locations, with continuation into Wednesday
  likely.
* Cold front approaches Wednesday, decreasing temperatures late
  week.

Details: Continued to increase temperatures Tuesday/Wednesday
from the NBM deterministic. Combination of dry surface
conditions and mostly sunny skies should allow for quick morning
warmup to around 90 for much of the forecast area. From here,
highs push into the low to mid 90s across the interior and even
mtn valleys. Along the coast (especially the Midcoast), light
onshore flow will tend to strengthen in the afternoon,
reinforced by seabreeze. Thus, temps along the coast peak early
afternoon, with a moderating airmass for remainder of the day.

The good news, despite this longer period of heat, is the
relative dryness of the airmass as well as good overnight
recovery temperatures in the 60s. Dewpoint temps will tend to
run low considering dry antecedent surface conditions, but there
won`t be enough momentum transfer to mix down even drier values.
This keeps heat index values close to actual temperatures.

Given the confidence in this airmass, have continued the Heat
Advisory set for Monday, into Tuesday as well. An extension
will likely be needed for Wednesday, but next incoming cold
front offers some uncertainty in cloud cover and possible
showers.

Consensus does keep precipitation largely west of the CWA into
early Wed afternoon, but can expect some clouds ahead. With
building CAPE and forcing, could see some showers and
thunderstorms develop ahead of the main forcing. However, lapse
rates are not steep and shear of around 20 kts could prevent a
more widespread thunder event.

Winds shift NW behind the front Thursday, with a dip in expected
high temperatures late week into the mid to lower 80s.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Short Term...Fog is expected to bring restrictions at valley
terminals, like LEB, again tonight, as well RKD. Elsewhere,
ceilings are expected to remain VFR overnight. Once any fog
clears in the morning, VFR will prevail areawide through Monday.
A similar fog setup can be expected Monday night.

Long Term...VFR conditions look to prevail, but there will be
the chance for some restrictions due to coastal and valley fog.
This appears most likely during the overnight and early morning
hours. Weak winds in the low levels present little risk of LLWS
development, with wind shifts expected around daily sea breeze
fronts.

&&

.MARINE...
Short Term...Wind gusts and seas remain below SCA criteria as
high pressure remains over the waters. Generally, south to
southwesterly flow continues through Monday night with gusts
10-15kts and seas 2-3ft.

Long Term...High pressure centered to the south
will keep conditions over the waters below SCA criteria. Expect
some marine stratus/fog to develop in warming air temperatures
this week. Onshore flow directions expected for the most part,
with diurnal sea breeze. Wave heights generally remain 2 to 3
ft.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for
     MEZ012>014-018>022-033.
NH...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for NHZ010-
     012-013.
MARINE...None.

&&

$$

NEAR/SHORT TERM...Baron
LONG TERM...Cornwell