306
FXUS61 KGYX 180704
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
304 AM EDT Wed Sep 18 2024

.SYNOPSIS...
High pressure lingers for one more day, but does begin to break
down tonight. Moisture over the southeastern states builds
north behind this this high with a slight chance for showers
over southern New Hampshire by Thursday. There may be a better
chance for showers Thursday night into Friday as low pressure
develops south of New England. High pressure builds in from the
north this weekend with more seasonable temperatures and dry
weather expected.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
The ridging from the sfc through 500 MB hangs around one more
day, but it is being broken by 500 MB closed low to our SW, and
by weak waves moving through the jet well to our N. So other
than morning fog weve become so used to, and some cirrus, it
should be another warm and mainly sunny day, although maybe more
of a filtered sunshine in the south. While maxes wont be as
warm as Tuesday, they will still be quite warm by mid September
standards, and range form the mid to upper 70s on the coast and
into the low to mid 80s inland.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
By tonight, there will be very little flow up through 700 MB,
and mid-level col settles overhead, and no real sfc gradient.
This should allow whatever sea breeze gets going this afternoon,
to persist, albeit weakly tonight, which will likely bring in
some marine fog fog and stratus to the coast later this evening.
Not sure, how far inland it will make it, but with higher Tds
and just some cirrus in the N half of the CWA fog is expected
in more places. Min temps will generally be in the 50s, low 50s
N, to upper 50s in S NH and SW ME.

Thursday is a more tricky forecast, at least for temps. Given
that weak sfc low will track from roughly W-E S of New England
should see an onshore E-NE flow develop. Although it will be
weak. This combined with more clouds on the coast and in S NH E
of the CT vly will lead to the coolest temps in these areas
/theres also a slight chance of showers in srn NH as well/,
with highs closer to 70 and probably some 60s on the immediate
coast. Most inland areas should make into the the mid to upper
70s, while the CT vly could see some reading near 80, given the
downslope and 850 MB temps temps still around 13-14C. I think
much of the CWA will see a partly sunny day, but S NH and the
coast will be mostly cloudy.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
12Z operational models and ensemble solutions continue to
indicate a disorganized area of low pressure will be centered
off the Northeast coast at the beginning of the extended period.
Moisture attempts to advect towards the Maine and New Hampshire
coastline with the best chances for precipitation Thursday into
Thursday night. Whether or not these showers will reach
southern portions of the forecast area will be highly dependent
on the amount of dry air in place over northern New England in
which the system would need to displace. For the time being,
will only have low probabilities for precipitation as our very
dry period continues across the region.

An upper level trough may bring a sprinkle or an isolated shower
to the interior of Friday. However, yet again any precipitation
would be very light. Otherwise, high pressure over eastern
Canada will keep us dry over the weekend and into early next
week.

Above normal temperatures on Thursday will be replaced by
seasonable readings for the remainder of the extended forecast.

Coastal Flooding...The onshore winds forecast for the coast late
in the week will coincide with very high astronomical tides.
This may lead to minor coastal flooding near the times of high
tide.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Short Term...Yet another morning with valley fog and maybe some
brief sunrise fog at KCON/KAUG/KRKD, but VFR should return and
persist through sunset. Coastal terminals will likely see some
coastal stratus move in later this evening, with some fog
possible, while valley fog should return to KHIE/KLEB. Probably
the coastal stratus will linger through much of the day at the
coastal terminals, but should improve somewhat later in the
morning. The rest of the terminals should see improvement to VFR
by mid morning, which should last through the day.

Long Term...VFR likely prevails during the day time Friday
through Sunday. Night time valley fog will bring the potential
for IFR/LIFR most nights at KLEB and KHIE. Onshore flow and
increasing clouds from a system passing south of New England
will also bring the potential for cigs around MVFR thresholds
Thursday night and possibly into Friday.

&&

.MARINE...
Short Term...Winds/seas stay below SCA criteria through Thu, but
will see seas start to come up during the day on Thu, as low
pressure moves offshore from the mid Atlantic coast.

Long Term...Winds and seas remain below SCA thresholds Thursday.
a northeast flow will develop Thursday as low pressure
approaches and stays south of New England. Low pressure passing
south of the Gulf of Maine will bring seas building to 5 ft by
Friday with continued NE flow with gusts around 25 kts. Seas
remain elevated around 5 feet into the weekend with NE winds
subsiding from their peak on Friday.

&&

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

&&

$$

NEAR TERM...Cempa
SHORT TERM...Cempa
LONG TERM...Cannon