916
FXUS61 KGYX 120331
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1131 PM EDT Tue Jun 11 2024

.SYNOPSIS...
Scattered showers and thunderstorms develop tomorrow as an
upper level low continues to slowly move through, with the most
widespread shower activity expected across the higher terrain.
Temperatures moderate on Thursday ahead of an approaching cold
front. The front crosses New England on Friday, with high
pressure building in behind the front for the weekend. The high
moves offshore early next week, setting up a moderating trend
with warm temps likely next week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
1130 PM Update... Minor changes to reflect latest observational
trends. Scattered showers continue across portions of the ME
foothills and mtns but they are beginning to show signs of
weakening. Still expecting patchy fog overnight through early
Wednesday morning.

Previously...
730 PM Update... Convective showers continue to slowly move
along the sea breeze boundary early this evening, which is
currently located over interior southwestern ME near the
foothills. There has been some training of showers over the last
few hours but rain gauge observations indicate most locations
have received 1/2" or less of rain with some locally higher
amounts. Latest hi-res guidance suggests these showers will
likely persist for a few more hours within a region of a few
hundred joules of MLCAPE. Made some minor adjustments to PoPs
based on latest radar trends and loaded in the latest
observations but the overall forecast thinking remains on track.


Previously...
Scattered showers will continue across the interior this
afternoon and early evening. Some remaining elevated instability
could keep a handful going into the evening, but generally
expect dry conditions for tonight.

Not terribly confident in the cloud forecast overnight. Daytime
cu should dissipate with loss of daytime heating, but moist
layer remains around 850mb. So its possible this cu just
flattens and causes occasional broken sky conditions overnight.
This complicates temp trends overnight, as well as the chance
for fog formation. Where clear skies do develop, think at least
valley fog will be possible...especially towards the Kennebec
valley and Midcoast.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
Almost a repeat day of Tuesday for Wednesday. Again instability
builds across the interior with HREF probs favoring around
500-700 j/kg of SBCAPE. This will promote airmass/popup
showers. Showers or storms in the afternoon may pack a little
more in the way of heavy downpour considering the amount of
CAPE, but shear is negligible. This low of value compared to
the instability will see showers with shorter lifecycles, but
slow moving. While the slow storm motion will be favorable for
isolated nuisance flooding in poor drainage areas, the lack of
shear maintenance will keep this threat low.

Shower activity dwindles in the evening with the loss of daytime
heating. More in the way of fog development will be possible
overnight, again in the valleys but also along the immediate
coast.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Overview...

A cold front passes through to close out the week, with high
pressure bringing dry and seasonable conditions for the weekend.
The high moves offshore next week, setting up an extended
warming trend with a ridge building across the eastern US.

Details...

A cold front approaches New England from the west on Thursday,
with increasing southerly flow bringing in warmer temps ahead of
the front. Temps warm into the 80s across most spots, with mid
to upper 70s expected along the coastline. Any showers or
thunderstorms are expected to hold off until after dark.
Weakening showers and a few thunderstorms reach into northern
areas during the overnight hours as the front approaches. The
front then crosses during the daytime on Friday. Showers are
still likely across northern areas early on Friday, but the
better chance for thunderstorms looks to be across southern
areas where more daytime heating can occur before the front`s
arrival. Some strong storms will be possible with the front as
dew points climb into the 60s during the day on Friday, but the
timing of the front will be important to see if we end up with
anything more widespread or severe. A delayed frontal passage of
only a couple hours increases this threat, so we`ll be
monitoring it over the next couple of days.

The front clears the coast Friday night, with high pressure
building in from the northwest for the weekend. The high brings
much drier air and mainly sunny conditions. Temps look
seasonable on Saturday, with northwesterly downslope flow
allowing the coast to warm to near 80, while the mountains stay
mainly in the mid to upper 60s. Saturday night looks crisp in
most spots, with lows mainly in the 40s and dry conditions.
Temps begin to moderate on Sunday as the high moves overhead,
with highs mainly ranging from the mid 70s to low 80s. A
seabreeze develops during the afternoon along the coast as the
high moves offshore, knocking back temps along the coast in the
afternoon.

The high moves offshore and begins to strengthen through
midweek, likely centered between Nova Scotia and Bermuda. This
is the sign at the surface of a building ridge across the
Northeast and Great Lakes next week, helping to bring some
potentially significant heat to New England next week.
Temperatures steadily moderate early next week, with highs into
the 80s for most areas in increasing southwesterly flow, except
for the MidCoast which holds in the 70s. Temps likely then warm
to near 90 in a lot of spots by Tuesday.

Afterwards, the heat looks poised to continue to build through
midweek as the ridge builds. As with the prospect of any period
of heat in New England from this far out, there are still of lot
of different factors that can serve as spoilers that we need to
remain mindful of. There will likely be leftover MCSs
transiting the ridge from the Plains, and uncertainty on whether
these will move through New England or north of the area. There
are prospects of a cut off low developing south of Atlantic
Canada, with the chance of this delivering a back door front
with easterly flow by late next week. So while all signs are
pointing towards heat at this point, there are still other
factors we need to remain mindful of as the possible peak of the
heat remains over a week away.

&&

.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
Short Term...VFR. Some valley fog or coastal fog will be
possible beginning tonight and perhaps lasting through Wed. SHRA
this afternoon across interior terminals will again occur Wed
afternoon, subsiding overnight.

Long Term...VFR conditions are expected on Thursday, then some
showers and storms bring brief restrictions to most terminals
Friday afternoon. VFR then prevails from Friday night through
early next week.

&&

.MARINE...
Short Term...Below SCA conditions with waves 2 to 3 ft and
southerly flog. Marine fog development will be likely over the
next 24 to 36 hours as humid conditions arrive.

Long Term...SCA conditions are possible Thursday night and
Friday ahead of a cold front. The front crosses the waters
Friday night. Fair conditions are then expected for the weekend
and early next week as high pressure settles along the Eastern
Seaboard.

&&

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

&&

$$

NEAR TERM...Tubbs