024
FXUS61 KCAR 070946
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
546 AM EDT Fri Jun 7 2024

.SYNOPSIS...
An upper level trough of low pressure will slowly approach
today...cross the area this weekend...then continue northeast into
the Maritimes on Monday. High pressure will build into the area
Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
543 am update...Added areas of dense for to coastal Downeast and
issued a Special Weather Statement for the fog.

Previous discussion...
An occlusion will make very slow progress eastward into the area
today as a blocking high gradually retreats into the Maritimes.
The area remains in a col between two large scale cut-off lows
within the omega block. The occlusion is weakening, but it is
moving so slowly that rainfall may accumulate to over one half
inch in areas of Piscataquis County, northern Somerset County,
and far northwestern Aroostook County. In contrast, the block
holds for eastern Aroostook County where dry conditions will
prevail today and highs will be some 10 to 15 degrees warmer
than where the showers linger all day in Piscataquis County. Not
really seeing any compelling reason to mention thunderstorms
today with the lack of surface heating or elevated instability.
That changes later tonight.

The other significant aspect to area weather today will be the
dense low level moisture and onshore flow ahead of the
occlusion. That is producing fog and drizzle towards the coast.
The coast will be shrouded in low clouds and fog all day. The
persistent low clouds under the frontal inversion will extend
northward to Bangor, Millinocket and Greenville throughout the
day with corresponding reductions to high temps.

For tonight, the occlusion remains parked over the area and the
low clouds/fog will thicken and move northward again. However,
dynamic changes aloft will reinvigorate the occlusion. The upper
low in the Great Lakes digs steadily towards New England during
the night. By late in the night, a strong vort max will rotate
around the base of the upper low into the area. This strong lift
and cooling aloft should result in heavier showers and
thunderstorm activity after midnight across the area. The
frontal inversion remains in place, so no severe thunderstorms
are anticipated but elevated CAPE is expected along with good
deep layer shear as the LFQ of a strong upper jet moves into the
area. Have increased and expanded PoPs and QPF over the CWA
after midnight.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
Upper level low pressure will be nearby to our west Saturday morning
while a surface occlusion extends east from this low to surface low
pressure over our region. Showers Saturday morning will be most
concentrated over central parts of the region supported by surface
convergence from the occlusion. From there, the showers will lift
north during the day as the triple point low slowly lifts north.
Cold air pooled aloft in the upper low will work with just a bit of
daylight heating to produce thin CAPEs of around 200 J/KG up to 25K
ft over central and northern parts of the area. Will keep a
slight chance for thunder central and north on Saturday. The
initial band of showers concentrated with the surface occlusion
will lift north and east of the area Saturday night. However,
moisture pooled in the upper low and some trailing weak
disturbances in the upper trough will continue to produce
showers and some drizzle overnight Saturday night, mostly across
the northern half of the region.

The upper low and surface trough will be draped across far northern
reaches of our region on Sunday resulting in wrap around showers and
drizzle continuing over the north. The surface convergence and cool
air aloft may again result in a chance for isolated thunderstorms
although soundings are not advertising as much instability Sunday,
only around 50 J/kg of CAPE, then they are for Saturday. Downeast
will chance have a chance for showers with some breaks of sunshine
possible further south of the low centers.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Low pressure, both surface and aloft, will be lifting away to the
northeast into the northern Maritimes on Monday. Hang back
troughiness and moisture pooled in the trough will continue to
result in low cloudiness and some showers scattered across the
north. There is just a bit of CAPE, around 50 J/KG, and a weak
trailing cold front approaching the region. This may result in some
isolated thunderstorms again on Monday, mainly north.

Low pressure surface and aloft will continue to weaken and move up
and away to the northeast on Tuesday. The trailing troughiness will
finally slide off to the east as high pressure and upper ridging
build in from the west. This will bring partial sunshine with inland
highs in the mid 70s.

Looking ahead to Wednesday, surface high pressure and upper level
ridging should remain over the area bringing a warm day with some
sunshine. Meanwhile, a new trough will begin to approach from the
west. The GFS is lifting some showers into southern parts of our
area late in the day Wednesday while other models are much weaker
with the approach of any showers. The uncertainty seems to be in the
interplay between a northern branch and southern branch shortwave
with the ECMWF keeping the southern feature south while the GFS
lifts the southern wave up the coast.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: LIFR conditions will prevail today for GNR, BGR and
BHB and could be VLIFR at times early this morning and again
tonight. IFR cigs will affect MLT and HUL this morning, but cigs
may lift to MVFR this afternoon. Further north towards PQI and
CAR, a period of MVFR cigs are expected this morning, but VFR
conditions return for the afternoon. All sites will become IFR
or worse tonight. Embedded thunderstorms are a threat all sites
after midnight.

SHORT TERM:
Saturday...IFR north, IFR to MVFR south. Light SW wind south and
light NE wind over the north.

Saturday night...IFR north. IFR To MVFR south. SW wind.

Sunday...IFR north and MVFR south. Light W wind.

Sunday night...IFR to MVFR north. MVFR to VFR south. Light W wind.

Monday...MVFR north. VFR to occasionally MVFR south. NW wind.

Monday night...MVFR to VFR north. VFR south. Light NW wind.

Tuesday...VFR. Light NW wind.

&&

.MARINE...
NEAR TERM: Fog will be the dominant feature through the period.
Cannot rule out thunderstorms late tonight. Seas will slowly
increase today as south swell increases towards 4 to 5 feet.
East winds will slowly become southeasterly by later today.
Gusts around 15 kt can be expected today, but decreasing later
today into tonight. Reduced guidance winds due to strong
stability.


SHORT TERM:
Wind and seas are expected to remain below SCA this weekend
through early next week. Moderately humid air over the colder
waters will likely result in some fog and mist over the weekend
into early next week.

&&

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

&&

$$


Near Term...MCW
Short Term...Bloomer
Long Term...Bloomer
Aviation...MCW/Bloomer
Marine...MCW/Bloomer