310
FXUS61 KCAR 040219
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
1019 PM EDT Wed Jul 3 2024

.SYNOPSIS...
A warm front will cross the region overnight through early
Thursday. A weak cold front will stall along the Downeast coast
Thursday night. The front then slowly lifts back north Friday
into Saturday. Another weak cold front will begin to cross the
region Sunday then will move east of the region on Monday.

&&

.NEAR TERM /THROUGH THURSDAY/...
10 PM Update:
Radar imagery shows shower activity beginning to move into far
northwestern areas. Additional shower activity is expected to
move in from the west late tonight. Slightly delayed and lowered
PoPs with this update based on trends in shower coverage to the
west, but the highest PoPs remain across the Saint John Valley
around and just after daybreak.

PoPs were adjusted for Independence Day to account for
significant dry air aloft that will be moving in from the west-
southwest by mid morning, which despite some CAPE should
inhibit convective development with a strong subsidence
inversion in the low levels and minimal synoptic scale lifting
mechanisms. Moisture trapped under the inversion should still be
enough for scattered to possibly broken stratocumulus, but
trended sky cover down slightly as well with this update,
especially across central portions of the forecast area.

Previous Discussion:
Latest sat/radar imagery shows clds and
shwrs advcg slowly ewrd from Cntrl QB toward Nrn ptns of the FA
with a leading band of virga or perhaps sprinkles ovr NW ME.
Most models weaken this band of shwrs as they move into Nrn ptns
of the FA later Tngt into erly Thu morn, with highest PoPs/QPF
ovr the NW and lesser amts SE of this area to little or none by
12z Thu for Cntrl/ Downeast areas. Greater cld cvr and/or shwrs
and breezier sfc winds from a weak llvl jet alf will keep ovrngt
lows at or abv 60 degrees at some inland low trrn lctns.

By Thu mid to late morn, most of whats left of any organized
shwr activity will move ENE of the FA as a weak upper s/wv
pivots out. This will leave the FA with ptly to msly cldy skies.
High temps Thu Aftn will reach arnd 80 deg F ovr low trrn lctns
inland from the coast, a few deg cooler than Tdy due to cld cvr
and any shwrs, but with more humid air, may feel more
uncomfortable. At least there will be a srly breeze.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
The low pressure to the north will swing the cold front through
the region Thursday night. QPF models are in some disagreement
with the amount of rain showers expected throughout the night.
However, after midnight, the model show that the majority of
rain showers will be out of the region with the cold front. With
ridging out over the waters and the low pressure to the north,
return flow should push the marine layer onshore. The question
will be how far north the fog will move in with the blocking
surface high pressure moving in. In addition, decided to include
light patchy drizzle for the coast with the upper air soundings
showing a moist column through the inversion. By Friday, high
pressure should linger through the morning with the next low
pressure intensifying over the Great Lakes. By the afternoon,
clouds should start to increase with the advancement of the warm
front moving across the waters, then north across the region.
Models indicate some instability with the frontal lift and
daytime heating, so isolated thunderstorms are possible.

By Friday night, showers should decrease with the warm front
moving north, but patchy fog will increase, especially across
the south. After midnight, shower chances will increase again
with the low pressure system moving from W to E. By Saturday,
the low will start to weaken as the rain showers progress. As
the cold front moves in by the afternoon, instability is
expected to increase. In addition, as of this update, models
show PWAT values near 2 inches, which gives concern of localized
heavy rain, especially with any thunderstorms that develop.
Temps expected to be near normal.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
The low pressure system is expected to exit to the E by Saturday
night with showers decreasing behind the system after midnight.
Very weak upper level ridging approaches Sunday and remains in
the region through Monday night. The next system is expected by
Tuesday, though the models are in disagreement with the low
pressure system track and timing as well as the cold front to
follow into mid week. Near normal temps expected.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
NEAR TERM:
Tonight to Thursday... VFR, except a period of MVFR
likely at KFVE and possible at KCAR/KPQI early to mid Thursday
morning with scattered to numerous showers. LLWS is expected at
northern sites through early Thursday morning. South winds 5-10
kt with gusts to 20 kt.

SHORT TERM:
Thursday night...VFR/MVFR early. A chance of showers with a
slight chance of thunderstorms north early. Variable conditions
with any thunderstorms. A slight chance of showers Downeast
early. Generally VFR late with showers ending. However,
variable conditions with any fog Downeast. South/southwest
winds 5 to 10 knots, becoming variable.

Friday through Friday night...Generally VFR. Slight
chance/chance of mostly afternoon and overnight showers.
However, variable conditions Downeast with any fog early Friday
then again Friday night. Variable winds 5 to 10 knots.

Saturday...VFR/MVFR early, then MVFR/IFR. A chance of showers.
Slight chance of afternoon thunderstorms. Variable conditions
with any fog early. Southeast/south winds around 10 knots.

Saturday night...MVFR/IFR, occasional LIFR, with showers and a
slight chance of thunderstorms. Variable conditions with fog.
South/southwest winds 5 to 10 knots.

Sunday...MVFR/IFR, occasional LIFR, in the morning. VFR/MVFR
during the afternoon. A chance of showers. Variable conditions
with morning fog. Variable winds 5 to 10 knots.

Sun night-Mon...VFR, with brief MVFR/IFR in patchy fog Sun
night. Light and variable winds.

&&

.MARINE...
NEAR TERM: No hdlns with winds and seas xpctd to remain below
SCA thresholds Tngt thru Thu. kept close to blended wv model
guidance for fcst wv hts with wvs composed of two groups with
pds of arnd 5 sec and 13-16 sec (distant propagating and
spreading swell from Beryl when still in the tropical Atlc)
respectively.

SHORT TERM: Winds and seas expected to remain below SCA
conditions through this period. Reduced visibilities in nighttime
patchy fog expected.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.

&&

$$


Near Term...MStrauser/VJN
Short Term...LaFlash
Long Term...LaFlash
Aviation...MStrauser/LaFlash
Marine...VJN/LaFlash