Area Forecast Discussion
Issued by NWS Portland, ME

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088
FXUS61 KGYX 032311
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
711 PM EDT Wed Jul 3 2024

.SYNOPSIS...
A weak warm front will approach tonight allowing a few light
showers, mainly well after midnight. A brief shower or two will
remain possible on Independence Day, but the vast majority of
the day will be dry. Higher temperatures and humidity begin to
build on Independence Day with this trend continuing through the
end of the week. The next chance for more widespread showers
and thunderstorms is expected this weekend.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
710 PM...Not too many changes attm to the forecast. Did tighten
up the timing of POPs later tonight, and generally in the N
they dont arrive until 06Z or later. OVernight mins look
reasonable generally in the 60-65 range across the board as
weak S flow persists and clouds move in later.

Previously...A relatively warm night is expected tonight as the
WAA pattern continues in advance of a weak warm front. Forcing
for ascent should increase and become sufficient for a few
showers to move into western zones and mountains late. Went with
moderate chance PoPs for measurable.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
Warm front works through the region in the morning with those
light showers dissipating. A warm and more humid air mass will
be felt in the wake of this front, but mostly cloudy skies will
persist, allowing for a slightly cooler day than today. A weak
cold front sags southward across the forecast area during the
late morning and afternoon hours. Forcing for ascent will be
weak at best, but with humid airmass in place amidst falling
heights, we cannot rule out an isolated shower or thunderstorm
during the afternoon.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Overview: An active weather pattern taking shape late this week
into the weekend. Low pressure is forecast to track from the
Great Lakes into eastern Quebec Friday and Saturday. This will
bring the chance for showers Friday, and again Saturday with the
added potential for thunderstorms and heavy rain. Some
uncertainty how quickly this system pulls east for drying
Sunday, but high pressure following the system should be
overhead by Monday. Another period of unsettled weather may be
in the region by the middle of next week, perhaps with more
potential to linger than this weekends system.

Details: Continued warmth Friday as weather pattern becomes
busy. The day may be punctuated by some afternoon showers and
thunderstorms developing across the interior. With weak shear
and marginal CAPE, currently see these as just providing an
isolated afternoon downpour with not much threat of hail/wind.

High pressure to the north will continue moving NE as low
pressure moves across the Great Lakes Friday and into Quebec
Saturday. Warm sector moisture keeps Saturday humid and damp.
Saturday likely sees the best chance for rain during the day,
with some thunder potential. Some guidance is robust with warm
layer aloft and CAPE suffers especially surface based
instability. The window for instability may be open a bit more
towards western NH, where a stronger storm cant be ruled out
given the strong shear and moist environment. At this point
however, the risk for heavy rain may be a larger but still muted
aspect. CWA PWATs push 2 inches Saturday with much of the
column saturated between early morning and early afternoon.
Additionally, the aforementioned warm air aloft keeps warm cloud
layers deep, around 13-14kft. So precip efficiency is there,
but the setup lacks favorable storm motion and features dry
antecedent conditions. Wed really need training storms Sat
(possible were CAPE to improve) and impactful shower activity on
Friday to increase odds of flooding Sat. One possibility is if
the following cold front slows, focusing rainfall along its axis
overnight into early Sunday morning, but best push of
efficiency parameters may be pulling east by then.

Sunday features less in the way of rainfall, but cant rule out
a few showers for the first half of the day. High pressure
nears the Northeast into early next week, providing a break of
the dreary weather Monday. This high will play a key role as it
exits the East Coast into Tuesday and Wednesday. Restrengthening
high pressure in the open Atlantic could allow for a focus of
unsettled weather to remain in the region mid week through late
week. A channel of moisture appears to get blocked and may align
with a good portion of New England and the East Coast as a
whole.

&&

.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
Short Term...VFR conditions today and tonight. A few patches of
valley fog possible tonight but coverage would be sparse. A few
widely scattered showers late tonight into Thursday could bring
a period of lowered conditions but overall, VFR conditions are
expected through Thu. A more moist airmass in place Thursday
night may yield greater chances for fog, especially at KHIE,
KLEB, KRKD.

Long Term...Mainly VFR Friday, but ceilings will begin to lower
in the evening and overnight hours. Many terminals will likely
see IFR to LIFR ceilings along with some reduced vis due to fog.
IFR lingers for mostly western ME terminals Saturday as SHRA and
some TS develop. A return to VFR may not be likely until Sunday
when high pressure moves towards the region.

&&

.MARINE...
Short Term...A few southerly gusts may approach 25 kt this
evening but sub-sca conditions are expected tonight through
Thursday night.

Long Term...The waters will spend much of the weekend within a
warm sector of passing low pressure to the west. This will
result in periods of fog or low stratus over the coastal waters.
Conditions may improve Sunday into Monday as a cold front slowly
moves over the waters. Onshore winds are expected through
Saturday, becoming SW Sunday and then W Monday.

&&

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

&&

$$

SYNOPSIS...
NEAR TERM...Cempa/Ekster
SHORT TERM...Ekster
LONG TERM...Cornwell/Dumont
AVIATION...
MARINE...