069
FXUS61 KGYX 071819
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
219 PM EDT Mon Sep 7 2026

.WHAT HAS CHANGED...
Increased chances for rain showers 10 to 20 percent tonight for
the northern half of the forecast area.

&&

.KEY MESSAGES...
1. A weak cold front will brush the area overnight with a
chance of showers mainly for the northern half of the forecast
area.

2. A seasonably strong low pressure system will drag a cold
front across the area late Wednesday into Thursday with showers
becoming likely late Wednesday and Wednesday night.

3. A period of gusty winds will be possible on Thursday behind
the front with dry weather returning late week through at least
Saturday.

&&

.DISCUSSION...
KEY MESSAGE 1 DESCRIPTION...

Just a perfect early fall day out there today. Diurnal cumulus
will dissipate after sunset and I expect mostly clear skies at
least during the first half of the overnight. A backdoor cold
front will be sagging towards the region late this evening, but
I do not think that significant prevents radiational cooling
early. As such I expect some valley fog to develop in the usual
locations prior to the clouds invading the area. Showers will
become more likely just before sunrise mainly across the
northern half of NH and the western Maine mtns into the Kennebec
River Valley. NBM PoP is pretty low given the CAM depiction of
precip and QPF, so I leaned on the HREF for timing and location
and brought the values up to 30 or 40 percent.

Briefly high pressure will drift across the region Tue afternoon
thru the overnight. That should allow for good radiational
cooling conditions again, despite return flow starting towards
daybreak Wed.

KEY MESSAGE 2 DESCRIPTION...

High pressure slides east Wednesday as low pressure moves
slowly east toward James Bay and sends a cold front toward New
England. Increasing southerly flow will advect higher moisture
into the region, potentially enough for some light showers
across the north, but mainly it will begin to feel more humid
out as dewpoints are forecast to climb into the upper 50s to
lower 60s with skies becoming mostly cloudy. Temperatures may be
limited to the 60s for northern areas due to more clouds while
southern areas still reach the 70s. With the slower approach of
the front, prospects for thunder have lowered.

The better chances for showers arrive Wednesday evening and
Wednesday night as the front enters the region and better
support moves in aloft. PWATs increase to 1.70" to 2.00" which
is well above the 90th percentile, meaning rain rates could be
briefly heavy at times. But with the fast-moving nature of the
system and drier antecedent conditions, not expecting any hydro
issues. Models continue to favor the northern half of NH
extending into the western ME mountains/foothills and Midcoast
for the higher chances/more QPF with ensemble means in pretty
good agreement of 0.25-0.50" although there are some
probabilities exceeding 0.50". Chances/amounts decrease with
southern extent, and there are hints that southern NH sees less
0.10", which is certainly not ideal.

KEY MESSAGE 3 DESCRIPTION...

Any lingering showers will come to an end Thursday morning with
much drier air moving in behind the initial front. West winds
will also ramp up in the morning and afternoon as mixing brings
down the higher winds from aloft and the surface low moves east
toward the Maritimes. Based on forecast soundings, gusts of
25-35 mph appear likely, but there could be a few exceed 40 mph,
per the top of the mixed layer. The cooler air doesn`t move in
until later in the day when a secondary front crosses, so it
will be a pretty warm day with highs expected to be upper 70s to
lower 80s south of the mountains.

Temperatures cool back down closer to normal for Friday and
Saturday with highs mostly in the 70s and plenty of dry air from
high pressure building into New England to keep skies mostly
sunny with low humidity. Friday night may bring excellent
radiational cooling to bring widespread lows in the 40s and some
30s across northern valleys.

The high shifts to the east by Sunday as another low pressure
moves across the Hudson/James Bay region with its associated
cold front approaching New England. This will bring another
chance of showers either Sunday and/or Monday, which is
supported by the 20-30% NBM PoPs in this time window.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
Through Tuesday...VFR conditions expected thru at least
midnight. I do think skies will be clear enough around midnight
for valley fog to form at both HIE and LEB. Eventually clouds
move in and some showers are possible which will help the fog
scatter out prior to sunrise. Showers will be possible mainly
thru the mtns to the Midcoast, there PROB30 groups have been
added to HIE, AUG, and RKD. Largely VFR conditions expected Tue,
but isolated showers are possible in the afternoon.

Outlook:

Wednesday: Mainly VFR but MVFR possible later in the day as
chances for showers begin to increase.

Wednesday night: A cold front brings widespread showers and
restrictions. Highest chances for showers and IFR to even LIFR
will be at HIE-AUG-RKD with lesser confidence in degree of
restrictions toward PWM and the southern NH terminals. Gusts out
of the S to SW around 20 kt possible.

Thursday: Mainly VFR with west winds gusting 25-30 kt, possibly
as high as 35 kt.

Thursday night-Saturday: Mainly VFR. Valley fog possible at HIE
and LEB by Friday night.

&&

.MARINE...
Winds and seas are expected to remain below SCA thresholds thru
Tue night. Then low pressure center moves east across Hudson
Bay toward the Canadian Maritimes Wednesday into Thursday, which
will send a cold front across the waters either late Wednesday
night or early Thursday morning...and then a secondary front
later in the day Thursday. Increasing south to southwest flow
ahead of the fronts will likely reach SCA levels from late
Wednesday into the first part of Thursday, and then possibly for
a period behind the second front Thursday night when winds turn
west to northwesterly. Conditions improve Friday and Saturday
as high pressure builds across the waters. The high shifts east
Sunday into Monday as another front approaches from the west.

&&

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

&&

$$

DISCUSSION...Legro/Combs