135
FXUS61 KGYX 191913
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
313 PM EDT Thu Sep 19 2024

.SYNOPSIS...
A low offshore from Cape Cod will churn in the atlantic for the
next few days, bringing the chances for marine fog and a few
showers tonight through the end of the weekend. Dry weather is
expected early next week with more unsettled weather arriving
for the second half of next week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Satellite imagery shows some clouds moving onshore from a low
offshore from Cape Cod. Radar is currently showing some showers
just offshore from Portland. These showers are moving very
slowly towards the coast. It`s tough to say whether these
showers actually end up making it to the coast, but there`s a
chance some coastal areas could see a few raindrops this
afternoon. This evening will feature some more scattered showers
just barely grazing the NH and southern ME coastline. Marine
fog and valley fog develop overnight and continue into tomorrow
morning.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/...
As the low offshore of southern New England retrogrades back
southward, cooler and drier air from New Brunswick will move
into the region and clear skies over land. The low will bring
some more clouds and perhaps some fog back into the coast
tomorrow night. Some leftover moisture could allow for the
development of a couple small showers tomorrow night, but the
rainfall amounts will be minimal.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Overview: Low pressure will begin to drift southeast over the
weekend. This will slowly decrease shower chances in southern NH
and ME. Impacts continue along the coast in the way of coastal
flooding during high tide, dangerous rip currents and beach
erosion caused by high surf. High pressure to the northeast will
keep deeper moisture at bay, bringing a dry stretch through
early next week. The next chance for area-wide rainfall appears
to be around midweek as low pressure spins into the eastern
Great Lakes.

Details: With the center of low pressure set to remain outside
the Gulf of Maine into the weekend, there will be a challenge on
spread of showers and QPF. Currently forecast the best chance
for showers to remain along the southern coast and inland across
far western ME and central/southern NH Saturday daytime.
NAM/Canadian regional both depict a small, weak inverted
troughing feature developing across southern NH that could
prolong or increase rainfall amounts. Global guidance is not
picking up on this as this moment, but will keep PoPs lingering
in the area albeit slight chance to chance. Also opted to lower
daytime highs Sat in southern NH given more cloud cover. Extent
of cloud cover is a bit more uncertain for the other two thirds
of the CWA, but model soundings depict substantial mid level
drying that should only keep some cu around beneath broken to
overcast cirrus.

Highlight for the weekend will be continuing surge and swell
from the offshore low. See the below section on Coastal Flooding
for more details there.

Temperatures will remain in the 60s through to midweek. High
pressure to the northeast will back cool, dry air into Maine.
Preliminary lows fall into the 40s as well, with lower values
possible should some of these nights be clear with calm winds.
The next weather system to bring a chance of rain to the area
arrives towards midweek. This will be another slow moving low
pressure system, and there is still uncertainty on timing and
how potent its source of moisture will be. The system attempts
to occlude in the eastern Great Lakes, and this plus the
downstream block tends to modify its translation east. So, the
forecast includes a period of shower chances later this upcoming
week due to this uncertain passage.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
Short Term...
Gradually lowering CIGs are expected along the this afternoon as low
stratus moves onshore. This evening, showers and some fog develop
along the coast, possibly lowering some CIGs to LIFR in more foggy
coastal locations. Visibility and CIGs along the coast recover
slowly through the day tomorrow. Tomorrow should be less foggy in
the CT River Valley, but LEB could see some low CIGs tomorrow
morning. Mostly VFR expected tomorrow but some localized lower CIGs
are possible due to isolated showers. Showers continue to lower CIGS
Tomorrow night and some patchy fog is possible in the valley
Saturday morning as well.

Long Term...MVFR ceilings improve towards VFR during the day
Saturday along with the chance for SHRA at southern terminals.
MVFR may work back in Sunday across a more broad area, but could
remain scattered under higher cirrus. General trend should be
towards VFR late weekend into early next week as high pressure
pushes in from the northeast.

&&

.MARINE...
Short Term...
Seas are expected to be around 2-5ft this afternoon, and strengthen
this evening as a low stalls offshore from Cape Cod. Light
northeasterly winds will strengthen overnight, with 25-35kt winds
expected tomorrow. SCA issuance is likely tomorrow, as seas increase
to 6-10 ft over open waters tomorrow afternoon, with 2-4 ft seas in
Penobscot Bay. Winds remain at 20-30 kts tomorrow night.

Long Term...Waves remain 6 to 10 ft over the open waters through
the weekend. Waves will be lesser in the bays and harbors, but
swell will still be elevated. The source low pressure system
will be slowly drifting southeast, and do expect these waves to
be on the downtrend as a result, but waves to 6ft may continue
into mid week.

&&

.TIDES/COASTAL FLOODING...
We are at the peak of our astronomical tide cycle through the
weekend with the highest tides occuring during the afternoon
hours. Meanwhile, a gale center will remain south of Cape Cod
over the next few days. This will lead to multiple cycles of
minor coastal flooding due to storm surge values approaching 1.5
feet, mainly from Portland and points south, however the
Midcoast may have some minor coastal flood issues or splash-
over as well by Friday afternoon.

Beach surveys and Emergency Managers continue to indicate
compromised dune systems along the coastline from our storms
this past winter. Therefore, building nearshore waves may lead
to additional splash-over or coastal flooding as well.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Coastal Flood Advisory from midnight tonight to 2 AM EDT
     Friday for MEZ023-024.
     High Surf Advisory from 8 AM to 7 PM EDT Friday for MEZ023-024.
     Coastal Flood Watch Friday afternoon for MEZ023-024.
     Coastal Flood Advisory from noon to 3 PM EDT Friday for
     MEZ025>028.
NH...Coastal Flood Advisory from midnight tonight to 2 AM EDT
     Friday for NHZ014.
     High Surf Advisory from 8 AM to 7 PM EDT Friday for NHZ014.
     Coastal Flood Watch Friday afternoon for NHZ014.
MARINE...Small Craft Advisory from 6 PM this evening to 8 PM EDT Friday
     for ANZ150>154.

&&

$$


NEAR TERM...Palmer
SHORT TERM...Palmer
LONG TERM...Cornwell
TIDES/COASTAL FLOODING...Cannon