603
FXUS61 KCAR 170541
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
141 AM EDT Tue Jun 17 2025

.SYNOPSIS...
High pressure continues to slide south of Nova Scotia Tuesday.
Low pressure will then pass northwest of the area Wednesday and
again on Thursday. A cold front will cross the area Thursday
night. A large area of high pressure will set up across the
Eastern Seaboard on Friday into Saturday.

&&

.NEAR TERM /THROUGH TODAY/...
1020 pm update...
Quick update late this evening as fog has been delayed in
developing but is finally showing signs of developing along the
Midcoast. Fog/low clouds can be seen moving into the swrn Gulf
of Maine at this time. Updated to delay fog development until
closer to 03z before quickly spreading inland as marine layer
moves rapidly north under strong low-level inversion. How far
north marine layer can spread remains in question but it appears
to only move twd Bangor and into the Princeton area tonight.
With mainly clear skies over central and northern areas cannot
rule out river valley fog to develop late tonight and have left
in forecast at this time. No other chgs needed.

Prev discussion blo...
Surface high pressure south of Nova Scotia continues to slowly
drift east tonight with increasing low level moisture off the
Gulf of Maine. The boundary layer tonight will moisten
significantly especially south of the Longfellow Mtns. Expecting
low level clouds and fog to develop tonight as a steep low
level inversion develops with moisture trapped below. S winds
become light tonight with temperatures falling back into the low
50s. Fog along the Downeast coast will likely become dense in
locations and the potential exists for a headline, will need to
monitor trends tonight.

Tomorrow will feature strong southerly flow off the cold Gulf of
Maine waters with intially a lot of clouds. Expecting a partly
sunny day especially across the northern 1/2 of the CWA. Deep
southerly flow 10-20mph will keep temperatures much cooler for
the southern 1/2 of the CWA south of the Longfellow Mtns. Have
opted to reduce highs significantly lower than NBM and other
guidance using 18-25th NBM percentiles and other hi-res
guidance. Highs generally 65-72F for the Bangor Region to Calais
to Downeast Coast, colder in the low 60s at the shore. North of
the Mountains expecting the warmest temps where in the North
Woods will be a downslope wind highs top out in the upper 70s to
low 80s. Warmest spots tomorrow will be the Estcourt area to
Fort Kent, rest of Eastern Aroostook top out in the mid to upper
70s. In the afternoon a few isolated to scattered showers
develop mainly across the North Woods and with up to 500j/kg of
SBCAPE cannot rule out a couple showers becoming robust enough
to produce a few lightning strikes mainly close to the Quebec
border.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY/...
The jet stream will remain to the north of the state through the
short term, and in this position will pull most low pressure
systems well north of our forecast area. That said, a weaker
shortwave may push up underneath this stream, bringing rain into
the forecast area from the south. The southerly flow will
continue to advect moisture in to the area, supporting the
development of fog across the Downeast region both Tuesday and
Wednesday nights. Another shortwave will approach from the west
on Thursday, with a trough of low pressure entering the area
Thursday afternoon. This front could spark the development of a
few thunderstorms, though these will mainly be confined to the
North Woods based on the timing of the low pressure into the
CWA, and how the boundary will slow as it approaches the marine
layer, which will have moved quite a bit inland due to
persistent southerly flow. That said, forecast soundings from
the NAM indicate that there could be up to 1000 J/kg of CAPE in
the North Woods Thursday afternoon with steep low level lapse
rates around 7 to 8 C/km and 40 to 50 kts of bulk shear, which
would support thunderstorm development.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Any thunderstorms that develop through Thursday afternoon will
dissipate into the overnight hours Thursday night, though
showers may linger across the north as the front slows and
potentially stalls across the center of the CWA. As the parent
low begins to lift NE away from the region, there is increasing
consistency across global models that this low could strengthen
as it departs, leading to a tightened horizontal pressure
gradient into our forecast area. This could lead to gusty winds
through the day on Friday, but that said, the deterministic CMC
does not have this solution at all. High pressure should build
in Friday into the weekend, leading to a relatively drier
pattern. That said, there could be a few isolated showers that
develop across the north should mid level moisture hang on long
enough to support their development on Saturday. Yet another
shortwave could approach the area from the west on Monday.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: BHB and BGR...Low stratus still developing over
Downeast but think IFR conditions will move into BHB and BGR
within the next 2 hrs. Drizzle and fog expected at both sites,
with VLIFR expected at BHB between 07z-12z. Slow improvement to
MVFR after 13z and a brief period of VFR after 18z before
diminishing to MVFR again after 00Z. IFR likely again late
tonight but confidence is not high enough to include at the end
of the TAF period.

Aroostook terminals likely to remain VFR next 24 hours. Cannot
rule out BCFG at HUL just before sunrise but confidence is not
high enough to bring vsbys down to MVFR.

All terminals will see southerly winds overnight, becoming gusty
in the afternoon.

SHORT TERM:
Tuesday night: Becoming MVFR/IFR with SHRA, with lowest cigs and
vis at Downeast terminals. FG is also possible Downeast. S winds
5 to 10 kts.

Wednesday: IFR early with SHRA possible, becoming MVFR at
northern terminals and VFR at Downeast terminals. SW winds 5 to
10 kts. IFR returns at southern terminals Wednesday night in
FG.

Thursday: IFR at southern terminals in the morning. Otherwise
VFR with tempo MVFR/IFR in the afternoon and evening with SHRA
and potential for a TS at northern terminals. S winds 5 to 10
kts, gusting to 20 kts or higher around any TS.

Friday: MVFR/VFR. SW winds shifting NW with high uncertainty in
speeds, ranging from around 10 kts to 35 kts depending on the
track and intensity of a nearby area of low pressure.

Saturday: All terminals improving to VFR. NW winds 5 to 10 kts.

&&

.MARINE...
NEAR TERM: S-SSE winds below SCA conditions through tomorrow.
Seas generally 1-3ft or less through tomorrow. Widespread fog
and areas of drizzle tonight will reduce vsby less than 1NM
tonight into tomorrow. Sea surface water temperatures from the
Hancock County coast out 25nm including Penobscot Bay ranges
from 48-51F this week. Water temperatures from the Washington
County coast out 25nm and east to the Hague Line including
Passamaquoddy Bay range from 45-49F this week.

SHORT TERM: Winds and seas likely to remain below SCA criteria
through the middle of the week, though borderline SCA conditions
may develop Thursday night into Friday as low pressure passes to
the north and winds increase, with gusts potentially approaching
25 kts and seas approaching 5 ft, though these conditions may
not quite reach this level if the low remains far enough north
and stable conditions linger across the marine zones. Fog likely
to reduce visibility Tuesday night through Thursday.

&&

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

&&

$$


Near Term...Buster/LF
Short Term...AStrauser
Long Term...AStrauser
Aviation...Buster/LF/AStrauser
Marine...Buster/LF/AStrauser