175
FXUS61 KCAR 272226
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
626 PM EDT Mon May 27 2024

.SYNOPSIS...
Low pressure will track to our northwest through Tuesday. Upper
level low pressure will remain over the area Wednesday into
Thursday then slowly lift to the northeast on Friday. High
pressure builds in for the weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
Update...
Warm front currently to our southwest across southern New
England will slowly lift north across the region late tonight.
Expect mainly cloudy skies overnight with increasing likelihood
of showers, mainly after midnight.

Just minor adjustments to current conditions otherwise no other
changes.

previous discussion
The large occluded low pressure system centered over Quebec
will swing a warm front north of the region, bringing rain
showers across the region tonight. Hi-res models are in good
agreement with the rain showers beginning this evening and
progressing from west to east throughout the night. Upper air
model soundings are also in good agreement with the presence of
elevated CAPE aloft. Due to the higher low level lapse rates
along Downeast and the progression of the warm front,
thunderstorms are expected to develop after midnight. In
addition, the PWAT values above normal, mean RH above 90
percent, and a large warm cloud layer will produce heavy rain in
some convective showers tonight. With the moist boundary layer
and steep inversion, patchy fog will develop across the region
with possible areas of fog across the south.

By Tuesday, the warm front will move through the region pushing
the rest of the showers off to the east by late morning. High
res models and RH models show a time of brief clearing in the
clouds before the cold front approaches the area. Though the
passage of the warm front will stabilize the area, this clearing
of clouds and sunny afternoon will help destabilize the region
again. The heating of the day and the frontal lift will start
producing thunderstorms in the afternoon. The ingredients are
present according to several upper air soundings for these
storms to create gusty winds and small hail.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
Thunderstorms with the cold front will end quickly in the
evening. The front will stall and fog will reform Downeast in
the humid air south of the front. Lows will drop to the low to
mid 50s.

For Wednesday, the trend was towards decreasing PoPs and clouds.
Nonetheless, sufficient moisture at 850mb in the northerly flow
will promote cu/stratocu fields in the north. The front sags
slowly southward into the Downeast region by afternoon.
Convergence along the front will generate showers and
thunderstorms Downeast, and possibly westward to Bangor. Some
guidance such as GEMS develop a shortwave moving through the
broader upper level trough to generate lift. A fair number of
models develops a narrow band of SBCAPE in the 500 to 1000 J/kg
range. The afternoon starts with sufficient shear to raise the
chance of stronger storms, but shear rapidly diminishes as the
afternoon progresses. Hail would definitely be a consideration
given the low freezing level if models continue to advertise the
stalled front Downeast. Strong winds seem unlikely unless there
is a particularly strong cell.

The front exits offshore Wednesday night with lows dropping
into the 40s to near 50F. Guidance has struggled with a another
shortwave rounding the base of the broad upper trough Wednesday
night into Thursday and whether it would move from southern New
England and brush the Downeast coast. Chances have trended lower
with the latest analysis and guidance, but have maintained
chance PoPs on the coast later Wednesday night into Thursday.
Further north, we have trended towards less cloud cover, but
seasonably cool highs in the low to mid 60s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A long wave upper trough will slowly move out of the area in
favor of a high amplitude upper ridge during the period. While
the upper trough remains in place, there is a chance of showers
towards the coast Thursday night. A few light diurnally-driven
showers may develop on Friday too, but the overall trend will be
towards lower PoPs and warmer temperatures as the week draws to
a close. The upper ridge begins building Friday and will crest
over the area Sunday into Monday. High temperatures will move
from just below seasonable norms on Friday towards slightly
above normal by Sunday into Monday.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
NEAR TERM: Aroostook Terminals...VFR/MVFR conditions this
evening will decrease to MVFR after sunset tonight in low cigs.
After midnight conditions will decrease again to IFR/LIFR
cigs/vsby in rain showers and patchy fog. LLWS all tonight. SE
winds 10-15 kts. By Tuesday, IFR/LIFR conditions throughout the
day with VCTS in the afternoon. SSW winds 5-15 kts.

Downeast Terminals...MVFR/IFR conditions this evening will
decrease to IFR/LIFR after sunset tonight and remain IFR/LIFR
for the rest of tonight in rain showers and areas of fog. LLWS
all tonight. SE winds 10-15 kts. For Tuesday, IFR/LIFR
conditions in rain showers and possible afternoon VCTS. SSW
winds 5-15 kts.


SHORT TERM:
Tue night...Fog is possible southeast of HUL and BGR to include
locations such as Princeton, Machias and Eastport. Thunderstorms
will quickly end in the evening. Otherwise VFR. Light SW winds.

Wednesday...VFR. A chance of afternoon thunderstorms towards
Machias, Eastport, BHB and possibly BGR.  NW winds 5 to 10 kt.

Wednesday night into Saturday...Prevailing VFR conditions. N to
NW winds 5 to 10 kt.

&&

.MARINE...
NEAR TERM: A Small Craft Advisory remain in affect through
tonight. It has been extended through Tuesday, especially in the
outer waters where seas will remain in SCA criteria. Reduced
visibility in patchy fog.


SHORT TERM: Seas just over 5 ft may necessitate extension of the
SCA for outer waters Tuesday night. Otherwise, light winds are
expected. Southwest winds on Tuesday night into Wednesday will
shift to northerly for Wednesday night into late week. Fog is
likely Tuesday night and is expected to move away from the
waters with a cold front on Wednesday.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until 8 PM EDT Tuesday for ANZ050-051.
     Small Craft Advisory until 2 PM EDT Tuesday for ANZ052.

&&

$$


Near Term...TWD/LaFlash
Short Term...MCW
Long Term...MCW
Aviation...TWD/LaFlash/MCW
Marine...TWD/LaFlash/MCW