Area Forecast Discussion Issued by NWS Caribou, ME
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000
FXUS61 KCAR 231340
AFDCAR
Area Forecast Discussion
National Weather Service Caribou ME
940 AM EDT Sat Sep 23 2023
.SYNOPSIS...
High pressure will move southeast of the region as a cold front
approaches from the northwest and falls apart over Maine today.
Low pressure will track well to our south tonight into Monday.
High pressure slowly builds into the area Monday afternoon
through Friday.
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.NEAR TERM /THROUGH TONIGHT/...
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9:30 am Update: High clouds from Tropical Storm Ophelia continue
to move across the area. A few thicker patches of fog remain
near Moosehead Lake, Mars Hill, and north of Mount Katahdin, but
these will continue to dissipate late this morning. Lower level
clouds around 3,000 feet AGL are moving into the Saint John
Valley just ahead of a weak cold front. This front will bring
isolated showers this afternoon, a few of which have already
developed northwest of Fort Kent. The front is still expected to
stall north of Baxter State Park this evening. No changes were
needed aside from importing the latest observations.
Previous Discussion...
High clouds from Tropical Storm Ophelia which is centered near
the North Carolina coast will continue to thicken in southern
zones this morning. Still expecting some milky sunshine through
the clouds in spots but basically cloudy day. A cold front with
mid level clouds is approaching the St. Lawrence seaway at this
time. This front will track into Northern Maine today and just
washout over the state. Expecting a wind shift this afternoon
across the north from S-SW to N-NW but remaining generally less
than 10mph. Southerly winds will continue across southern zones
with the influence of Ophelia well to our south. Expect
temperatures to be warmer north with more sunshine and cooler
towards the coastline along with the wind off the Gulf of Maine
waters. Highs along the coast in the upper 50s to low 60s.
Bangor region into interior Downeast will be mid 60s with upper
60s to near 70F closer to Baxter & Moosehead you head. Across
the north into the Crown expecting upper 60s to low 70s in
spots.
Tonight, expect a piece of Ophelia energy to break off and track
south of the Gulf of Maine waters with precipitation. Not
expecting any precipitation onshore here in Maine as the front
washes out over the state. Winds lightly shift N in response to
a 1026mb high pressure building SE into Quebec and Northern
Maine. Winds become light tonight and with no strong pressure
gradient expecting a nice calm night. It will be mostly cloudy
south which will keep temperatures up but strong clearing to the
north will result in some cooler temperatures. Expecting some
lower 40s across the north with upper 30s in the far NW that
might produce some patchy frost. Elsewhere, with thicker clouds
expecting upper 40s to around 50F at the shore.-- End Changed Discussion --
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.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Sunday will feature high pressure nosing into the area from
northern Ontario and Quebec. H850/925 temps support highs in the
upper 60s to around 70F with low humidity. Northern zones will
see little cloud cover, but towards the coast, a cirrus overcast
will be in place much of the day.
The cirrus will be the northern edge of the deeper moisture
associated with remnants of Ophelia in the Mid- Atlantic states.
This moisture will stay well south of the area Sunday night.
An upper trough swinging southward from northern Quebec will
shunt the moisture south and east of the area. A cold front
associated with the upper trough moves through the area Sunday
night with no precipitation, but decent cold air advection and
breezy north winds.
With H850 temps dropping towards the 1-3C range by later Monday,
high temps will struggle to reach much more than 60F in northern
zones on Monday. Mid 60s are forecast towards Bangor and the
Downeast coast where offshore winds will be in place. H850
moisture should be sufficient for partly to mostly cloudy skies
across much of eastern and northern Maine on Monday. Cool north
winds gusting to 20 mph will add to the fall-like feel on
Monday.
Clear skies, light winds and the cool air mass will produce
widespread readings in the 30s Monday night. Have added some
mention of patchy frost as well as river valley fog.
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.LONG TERM /TUESDAY THROUGH FRIDAY/...
A large blocking high over James Bay will slowly drift
southeastward towards Maine during the period and ensure an
extended period of dry and seasonably mild weather. Tuesday will
be the coolest day with a gradual warming trend in accordance
with the strong subsidence. The subsidence and low PWs promise
little cloud cover through the period. There will still be some
residual H850 moisture for thin fair wx cu and stratocu on
Tuesday. Highs will increase from the mid 60s on Tuesday towards
the lower 70s by Friday, but well short of record highs in the
lower 80s for Bangor and Caribou. Given the dry air mass, did
shade lows a bit lower than most guidance, but do not foresee
frost after Monday night. River valley fog will continue to be
an issue each night well into the week.
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.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
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NEAR TERM: VFR. Generally high cigs across southern sites.
Northern sites around FROPA expecting SCT-BKN MVFR cigs for a
few hours this afternoon. Winds S-SW 5-10kt this morning
shifting N-NW at northern sites this afternoon and evening.
-SHRA possible at FVE & CAR this afternoon. VFR cigs expected
tonight with BCFG possible at some sites. N-NW winds less than
5kt.
SHORT TERM:
Saturday into Wednesday...Predominately VFR with infrequent
cigs...mostly above 5000ft...and very good vis. Slight chance of
river valley fog impacting terminals near sunrise on Sunday
morning as well as early Tuesday and Wednesday mornings.
Generally light winds.-- End Changed Discussion --
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.MARINE...
NEAR TERM: Light S winds across the waters today generally less
than 10kt. Winds shift NE tonight and remain less than 10kt.
9-10sec period waves this morning will last into tonight
generally 1-2ft today becoming 1-3ft tonight. Sea surface
temperatures are running generally 54-57F across the waters
south of Washington County to the Hague Line. 55-58F from
coastal Hancock County out 25nm. Water temps are near 60F in
Penobscot Bay.
SHORT TERM: No fog or advisories likely through the period. NE
winds will kick up Monday into Tuesday with gusts in the 20 to
25 kt range. Long period south swell will reach around 4 ft
Sunday into Monday.
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.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.
&&
$$
Near Term...MStrauser/Sinko
Short Term...MCW
Long Term...MCW
Aviation...MStrauser/Sinko/MCW
Marine...Sinko/MCW