383
FXUS61 KGYX 070359
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1159 PM EDT Sat Jul 6 2024

.SYNOPSIS...
Scattered showers and thunderstorms diminish as a weak cold
front crosses the area late tonight. High pressure builds over
the region on Sunday and remains over the area into the early
next week bringing mostly dry conditions. The next chance for
showers and storms will be late Tuesday and Wednesday as another
front moves into the area.

&&

.NEAR TERM /UNTIL 6 PM SUNDAY EVENING/...
1155 PM Update... A line of gusty thunderstorms is currently
moving across portions of Cumberland, southern Oxford, and
Androscoggin Counties in ME with the latest SPC mesoanalysis
showing it moving into an area of up to around 1500 J/KG of
SBCAPE. Base velocity shows between 30-40 kts of wind and
therefore went ahead and issued an SPS. This line of storms
should fall apart once it moves towards the coast as it
interacts with the marine layer but it could remain somewhat
more organized further inland as it moves eastward. Otherwise,
showers and storms are expected to diminish through the late
night hours with fog developing. Made some minor adjustments to
PoPs but no major changes were needed.

Previously...
910 PM Update... Showers and thunderstorms continue across
portions of southwestern ME, southwestern NH, and along the CT
River Valley in Grafton County. Storm intensity has been
decreasing over the last few hrs as many areas have been
worked over and sfc instability is fading with the loss of
daytime heating. The main area of concern is over southwestern
Cheshire county NH where training of storms has been ongoing for
the last few hrs. Rain gauges indicate though that rainfall
rates are fairly tamed at around 0.50-0.75"/hr and therefore
will allow the flood advisory to remain in place. Made some
minor adjustments to the forecast through tonight.

Previously..
Scattered showers and a few thunderstorms continue to form
ahead of a slow moving cold front this afternoon, and gradually
make their way toward the coastline by the evening hours. After
this morning`s convection, most of the storms look to remain
fairly tame, but with the heating this afternoon a few strong
storms can`t be ruled out. The best chance for this would likely
be across southwestern New Hampshire, which has had a couple
more hours of heating so far today.

Most of the activity winds down through the evening, with just
a few lingering showers near the coast after midnight. The front
doesn`t bring any appreciable airmass change tonight, so a warm
and muggy night is expected again. Lows dip into the upper 60s
to low 70s south of the mountains, with some low to mid 60s
across northern areas where some relatively drier air starts to
make its way in overnight. Given the airmass, patchy fog is
expected to develop again tonight, with marine fog moving inland
overnight, and radiation fog elsewhere. Winds shift to westerly
and begin to bring slightly drier air in, helping to gradually
mix out the fog toward daybreak tomorrow.

&&

.SHORT TERM /6 PM SUNDAY EVENING THROUGH MONDAY/...
The front stalls nearby tomorrow, likely just offshore. Weak
high pressure tries to push in from the west, helping to bring
in some relatively drier air, with dew points mostly in the 60s.
Given the weak pressure gradient, a sea breeze is expected to
develop along the immediate coast tomorrow, holding highs to
mostly the 70s. Inland, temps warm into the upper 80s to near 90
in most spots, with highs in the low 80s across northern
locations. Given the airmass, a few pop up showers or an
isolated thunderstorm are likely tomorrow, especially across the
higher terrain. But otherwise, a return to more sunshine is
expected for tomorrow.

The high makes little progress into New England tomorrow night,
keeping the humid conditions ongoing with lows mainly in the
60s. Some patchy radiation fog is likely again tomorrow night,
but doesn`t look to be as widespread as tonight. Otherwise,
conditions look pretty quiet for tomorrow night.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A rather warm and muggy pattern to continue in the week ahead with
increasing chances of showers and thunderstorms Tuesday and again
late week. although most of the time it should remain dry.

The overall pattern in the long term can best be described as a
typical mid summer pattern with high dewpoints and a weak upper
level flow.  In the dallies starting with Monday, weak high pressure
will make for a dry and warm day. On Tuesday a weak cool front will
approach from the Great Lakes area. Moisture will surge ahead of
this front along with increasing instability.  Would expect showers
and thunderstorms to develop during the late Afternoon and continue
during Tuesday Night into Wednesday.  The front will try to cross
the area Wednesday morning after which showers would diminish. Given
the high dewpoints can`t rule out scattered showers or
thunderstorms. New GFS is wetter than previous runs and stalls the
front over the area.  Will need to see if that trend continues...if
so then Thursday could be wetter. Later Friday into Saturday
tropical moisture originating from the south may ride north toward
New England.  Have raised pops some over the NBM as this could
produce more organized showers by weeks end. Given how high the dew
point temperatures will be all week, added patchy fog most
nights.

&&

.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
Short Term...Some brief showers, and a low prob of a
thunderstorm, move through most terminals this afternoon and
evening from west to east. Marine fog brings IFR to LIFR along
coastal terminals again tonight. Valley fog may also bring a
brief period of restrictions to inland terminals later tonight,
then conditions improve to VFR tomorrow morning. Fog may linger
at RKD into tomorrow morning again, but overall improving
conditions are expected, with mostly VFR conditions tomorrow.
Nighttime valley fog is possible and may bring restrictions
again tomorrow night, but doesn`t look as widespread as tonight.

Long Term...VFR to MVFR conditions Monday into Tuesday as
week high pressure i early Thursday with isolated showers.
otherwise VFR conditions Thursday Midday lasting into Saturday.
overhead.  A cool front will result in showers and thunderstorms
Tuesday Afternoon and night bring areas of IFR.  Conditions improve
Wednesday into Thurday as high pressure returns resulting in MVFR to
VFR conditions.

&&

.MARINE...
Short Term...A weak cold front approaches from the west
tonight, and stalls near the waters tomorrow. Locally dense fog
continues across the waters into tomorrow, before some
improvement it likely late. Otherwise, fair conditions are
expected tomorrow and tomorrow night as weak high pressure
gradually builds in.

Long Term...Wind and waves may approach SCA levels Tuesday
otherwise an extended period of relatively light winds and low waves
are expected through Friday.

&&

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

&&

$$

NEAR TERM...Tubbs