Machiasport, Maine Weather Forecast Discussion

392
FXUS61 KCAR 180621
AFDCAR
Area Forecast Discussion
National Weather Service Caribou ME
221 AM EDT Thu Sep 18 2025
.SYNOPSIS...
A cold front will approach this evening and cross the region
tonight. High pressure will build toward the area Friday, cross
the region Saturday then exit across the Maritimes Sunday into
Monday.
&&
.NEAR TERM /THROUGH FRIDAY/...
Sfc low located east of the Delmarva over the Atlantic will continue
to move to the north and east this morning. Regional radars showing
echoes over the Downeast coast but very little in the way of
measurable rain has been reported. Reports from two wx stations
along the coast have reported 0.01 inches of rain though unclear if
it is actual rain or condensation from fog over the area. Marine
layer has advanced into interior Downeast with low clouds, although
hard to see on nighttime microphysics with mid-high clouds streaming
in. Area webcams confirm the existence of low stratus and fog this
morning. Expect the marine layer will approach the Houlton area but
may fall just short before retreating back to the waters.
Sfc low moving into the North Atlantic off of the coast of
Newfoundland/Labrador has draped cold front through southern Quebec
as of 06z. Showers and an isolated storm along the boundary will
continue to advance twd the region today. Temps will rise above
normal once again today just ahead of the front in warm advection.
Showers look to press into the St. John Valley around 21z. An
isolated thunderstorm will be possible over far nrn Aroostook County
this afternoon.
As the front pushes south into central sections through midnight it
will run into increasingly drier airmass and rain does not look to
fall south of the I95 corridor. All told, amounts of around 0.10
inches will mainly be confined to nrn Aroostook County.
The bigger story with the cold front will be the colder and drier
air following in it/s wake. Northwest winds gusting to between 25-
30mph on Friday will be ushering in H8 temps dropping below 0C. Dry
airmass will likely drop dewpoint temps down into the 20s acrs the
north. Temperatures will remain in the 50s acrs the north, lwr 60s
for central areas with temps around 70F over Downeast for highs.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
Friday Night...Mostly clear and dry with cold advection continuing
from the northwest. Airmass becomes quite chilly, but there
will still be enough of a pressure gradient and wind that most
places will have limited decoupling, especially eastern portions
of the area. Even with less decoupling, still expecting lows in
the upper 20s to mid 30s north/northwest, ranging to the upper
30s to low 40s Downeast.
Saturday...Seasonably cool and sunny with highs in the mid to
upper 50s north, and low to mid 60s Downeast. Northwest breeze
10-15 mph with gusts around 20 mph. Very dry air with afternoon
relative humidities around 30 percent. Lowered dewpoints a bit
from NBM thanks to good expected mixing.
Saturday Night...High pressure moves overhead with clear skies
and light winds, setting the stage for the coolest night of the
season for most places. Went a bit cooler than NBM for low
temperatures because of good decoupling/radiational cooling.
Frost appears likely even down close to the coast, with a freeze
likely for valleys over about the northern half of the area.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Sunday and Monday...High pressure moves east and we undergo a
warming trend. High temperatures Sunday return to around
average, and warmer than average on Monday with low to mid 70s.
Showers possible (20-40 percent chance) Monday in the north.
Tuesday and Wednesday...While models are in decent agreement
through Monday, agreement drops off Tuesday into Wednesday and
forecast confidence decreases. Most models/ensembles seem to
have an amplifying trough moving in from the north, with a
chance of showers both days as that trough approaches or moves
through. However, a lot of disagreement on the amplitude and
timing of the upper trough and probable associated cold front
that would move through from northeast to southwest.
Tuesday/Wednesday doesn`t appear to have the potential to be a
significant wetting rain, but the possibility does exist for a
quarter or half inch if things transpire well. Or it could be
like a lot of other systems and leave the area dry. It`s just
too early to tell.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR for northern terminals today into this evening. May
see MVFR cigs work in late in the TAF period behind cold front
but did not include in 06z forecast.
HUL looks to remain VFR next 24 hours. Question remains regarding
cigs early this morning as marine layer (i.e. low stratus) will
approach the terminal from the south. Have included SCT012 for
clouds between 10z-12z this morning given low confidence.
BGR and BHB will vary between IFR/LIFR this morning in low stratus.
BHB should drop to LIFR after 07z before improving to IFR after 13z,
and then VFR after 15z this morning.
BGR looks to drop to IFR between 09z-12z this morning, then improve
to VFR after 13z.
May see another round of IFR late tonight into early Friday morning
at BHB with variable conditions at BGR. For northern terminals may
see a brief period of MVFR cigs late tonight before all terminals
improve to VFR by Friday afternoon in wake of cold front.
SHORT TERM:
Friday Night and Saturday...High confidence in VFR areawide. NW
wind 5-10 kts Friday night, then 10 kts Saturday with gusts
15-20 kts.
Saturday Night...VFR early, then highly variable conditions
with patchy valley fog. Light winds.
Sunday through Monday...Mainly VFR, with possible late
night MVFR/IFR near the coast Sunday night. Possible MVFR far
northern Maine late Monday, but low confidence. S/SW winds 5-10
kts.
&&
.MARINE...
NEAR TERM: Winds and seas below small craft levels through the
end of the period. Seas generally ranging from 1-3 feet. SW wind
less than 10kts today will become northwesterly Friday morning
with gusts approaching 20kts over the outer waters late Friday
afternoon. Visibilities likely to be reduced in patchy fog today
and tonight.
SHORT TERM: Conditions generally below small craft Friday night
through Monday. However, NW winds gusting up to 20 kts are
likely Friday evening, which is just below small craft levels.
Also, seas build to 4 ft Monday, which is just below small
craft levels.
&&
.FIRE WEATHER...
Any showers with the cold front Thursday night will produce
generally less than 0.1 inches of rain, and mainly over the
north. Breezy and cooler conditions are expected Friday with
northwest wind gusts of 25 to 30 mph expected. Northwest winds
will gust up to around 20 mph Saturday. Dry conditions are
expected across the region Friday through the weekend. Minimum
afternoon relative humidities Friday should range from 30 to 40
percent, then around 30 percent Saturday.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.
&&
$$
Near Term...Buster
Short Term...Foisy
Long Term...Foisy
Aviation...Buster/Foisy
Marine...Buster/Foisy
Fire Weather...Foisy

NWS CAR Office Area Forecast Discussion