230
FXUS61 KCAR 130108
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
908 PM EDT Sun May 12 2024

.SYNOPSIS...
High pressure remains across the region tonight, then exits
across the Maritimes Monday. A storm system approaches from the
west Monday night and Tuesday, crosses the region Wednesday,
then exits across the Maritimes Thursday. High pressure builds
in Friday.

&&

.NEAR TERM /THROUGH MONDAY/...
9:08 PM Update: Water vapor satellite shows a mid level low
centered in the Gulf of Maine. The low is expected to slowly
move east tonight and should be along or near the southern coast
of Nova Scotia by Monday morning. The last of the showers are
dying out in southern Maine as moisture rotates around the low.
Cumulus fields across the FA will dissipate late this evening
and overnight, but there are some mid level clouds moving out
out of the Bay of Fundy and into Washington County. Low levels
remain dry, especially across the north, and there is the
potential that if the clouds fully clear that northern valleys
could get down to around freezing. Currently the coolest temps
in the 40s are along the coast with 50s still common inland. Not
planning any significant adjustments to the forecast at this
time.

Previous discussion:
A 500 mb trof slides east through the Gulf of Maine toward Nova
Scotia overnight. At the surface, high pressure extending from
the Canadian Maritimes to the mid atlantic, will move east.
Expect partly cloudy and dry weather tonight along with light
wind. Lows tonight will range from the mid to upper 30s north,
to near 40 for Bangor and Downeast.

The fair weather pattern continues through most of the day on
Monday. The 500 mb trof axis continues to slide east through the
Canadian Maritimes and this allows ridging to build in later in the
day. Surface high will continue to drift out into the western
atlantic with light southerly flow in place across the region.
Expect a dry day with partly sunny skies and highs in the mid to
upper 60s away from the coast.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
Upr lvl ridge axis will be over the CWA Mon evening with
longwave trof extending from James Bay down into the srn Plains.
Trof will creep eastward Monday night with a tendency to
flatten the ridge/shove it into ern Canada which allows return
flow to kick in, leading to an increase in dewpoints along with
showers moving in a after midnight. Warm advection with the
approach of a warm front will bring fog to western and coastal
regions late Monday night and with fog and cloudy skies mins
will be above normal in the middle 40s by Tuesday morning.

Warm front will lift through on Tuesday with chances for rain
increasing in the afternoon. Warm advection will be competing with
showers and rain with highs topping out just below normal. Rainfall
amounts on Tuesday will range from a few hundredths of an inch right
along the coast to around 0.25 inches over portions of the North
Woods.

Waves of low pressure will ride up along quasi-stationary boundary
on Tuesday night and highest rainfall totals are dependent on where
boundary sets up. 12z GFS has it setting up along the coast while
NAM/CMC/EC keep it fairly stationary over nrn zones. Given this
uncertainty have mentioned likely rain across the north early and
slowly dropping toward the coast late with amounts on average around
0.20 inches.

For Wednesday have continued with idea of cooler temps acrs the
northwest with rain likely south of this area.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
By Wednesday night CWA will still be in upr lvl trof axis as
stronger wave looks to be in the vicinity of the waters. This will
result in showers becoming more scattered acrs the north overnight
with still a good chance for showers over southern areas. During the
day will see precip very slowly wind down from north to south with
temps well above normal, close to 70 in the St. John Valley to near
60 along the coast with more of an along-shore wind remaining.

Depending on which model you look at,  Thursday night Friday
could be dry or maybe a shower or two. EC/CMC and their
ensembles indicate H5 ridge will be over CWA while GFS and it/s
ensemble indicates s/wv approaching from the west and this may
be enough to kick off afternoon showers with diurnal heating,
especially with temps in the lower 70s hitting convective
temperatures. For this reason have went with NBM pops and a
slight chance for showers Friday afternoon.

Active pattern looks to continue into next weekend with chances
for showers along with above normal temperatures, mainly due to
warmer low temperatures.

&&

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
NEAR TERM: High confidence VFR at the Aroostook County terminals
through Monday, although there is a very small chance of late
night/early morning fog patches at KPQI or KHUL, but chance is
too low to mention in the 00z Tafs. Medium to high confidence
of VFR at KBGR and KBHB through Monday. Small chance (less than
15%) of patchy fog or low cloud late tonight/early Monday
morning, but looking at upstream satellite pictures and latest
guidance it would indicate that the chance is too low to
mention in the 00z Tafs. Light and variable wind overnight will
become south and increase to 5 to 10 knots Monday afternoon,
except 10 to 15 knots at KBHB owing to the development of a sea
breeze.

SHORT TERM:
Monday night...VFR early becoming MVFR after midnight in light
showers and possible IFR late over Downeast terminals in patchy
fog. S 5-15kts.

Tuesday-Wednesday night...MVFR/IFR in rain and patchy/areas of
fog at times. S 5-15kts with gust to near 25kts on Tuesday,
then S 5-10kts Tuesday night/Wednesday becoming N 5-10kts late
Wednesday night over Aroostook terminals.

Thursday-Friday...Mainly VFR with ocnl MVFR cigs. NNE 5-10kts
Aroostook terminals, ESE 5-10kts Downeast Thursday/Thursday
evening, then ESE 5-15kts Friday.

&&

.MARINE...
NEAR TERM: Winds/seas remain below SCA levels through Monday.

SHORT TERM: Winds approach SCA levels over the outer
waters Tuesday and Tuesday night before diminishing below 20kts
through the end of the week. Seas approach 5ft Tuesday into
Wednesday morning before dropping under SCA levels through
Thursday morning. Seas may approach SCA levels again Thursday
into Friday morning.

&&

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

&&

$$


Near Term...CB/TWD
Short Term...Buster
Long Term...Buster
Aviation...CB/TWD/Buster
Marine...CB/TWD/Buster