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000
FXUS61 KCAR 251853
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
253 PM EDT Thu Apr 25 2024

.SYNOPSIS...
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High pressure will build across the region through Friday night
then slowly exit to the south and east through the weekend. A
warm front will lift through the region Sunday, then push back
south through the region as a cold front Sunday night and
Monday. High pressure then builds into the Maritimes through
Tuesday as a storm system approaches from the west.
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.NEAR TERM /THROUGH FRIDAY/...
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The upper level trof will continue to push the low pressure
system out over the Maritimes and usher a larger surface high
pressure system into the region tonight and Friday. For tonight,
high res models show the relaxing pressure gradients with the
center of the high pressure moving across the Great Lakes. This
will decrease W winds to be fairly light throughout the night.
The 925mb model temps show the cold airmass still over the
region. In addition, a very shallow, dry inversion at the
surface with little to no cloud cover will drop temps into the
20s across the region with teens in the North Woods.

By Friday, the center of the surface high pressure will be
sitting right over the region, making for a sunny, light wind
day. Model temps indicate that the high temps for the day will
return to more seasonable 50s. The vorticity models show some
shortwave energy moving across the north in the afternoon, but
with the dry column, only high clouds are expected to develop.
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.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
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Deep layered ridging builds in Friday night through Saturday
night, with its northern axis pushing to the east on Sunday as
northern stream trough passing over Quebec flattens the top of
the ridge.

It should be dry as a result with minimal cloud cover Friday
night through Saturday night due to subsidence under the ridge.
With light winds should have decent radiational cooling
conditions at night, so went towards the 18th percentile of
guidance for lows both nights. For highs on Saturday and Sunday,
since the area is prior to greenup - guidance often is too
cool, so went towards the 83rd percentile of guidance for highs.
Also undercut dewpoints during the day Saturday, leaning towards
the 18th percentile for dewpoints which is fairly close to where
a blend of MOS would be.

Lows Friday night should be around 10 degrees below normal,
ranging from the mid 20s to lower 30s. Highs on Saturday should
be around 5 degrees above normal, generally from around 50 near
the immediate coast to around 60/lower 60s inland. Lows Saturday
night should be near to slightly above normal.

As the northern stream trough passes to the north Sunday, it
could trigger some isolated to scattered showers, with the best
chance across the North. Low level warm advection could make
Sunday a few warmer than Saturday away from the coast, despite
having more cloud cover.
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.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
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Deep layered ridging re-establishes itself over the region
Sunday night through Monday night, so other than possibly some
lingering showers Sunday evening it should be dry.

A northern stream system approaching from south central Canada
should beat down the top of the ridge again on Tuesday and
Tuesday night, this should allow for some warm advection rains
to move in.

The question on Wednesday is does the deep layered ridge re-
establish itself, or does the northern stream system moving into
Southeastern Canada dominate. The former would suggest a dry
Wednesday, while the latter one at least the risk of some
showers. For now, there is quite a bit of uncertainty which of
the two scenarios will play out, so opted for isolated to
scattered showers for now.

Temperatures should be above normal Sunday night-Monday night,
near normal Tuesday and possibly remain so on Wednesday. Quite a
bit of uncertainty on temperatures on Wednesday.
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.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
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NEAR TERM: VFR conditions for tonight and Friday for all
terminals. This evening, NW winds 5-10 kts will quickly decrease
to light and variable winds for the rest of the night. For
Friday, NW winds 5-10 kts.


SHORT TERM:
Friday night-Saturday night...VFR. LLWS possible Saturday night.

Sunday-Sunday night...MVFR or lower possible, then becoming VFR
later Sunday night. S-SE winds G15-20KT possible Sunday.

Monday-Monday night...VFR. N winds G15-20KT possible Monday.

Tuesday...MVFR or lower possible.
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.MARINE...
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NEAR TERM: Winds and seas will remain below SCA conditions for
tonight and Friday.


SHORT TERM: A relaxed pressure gradient over the waters Friday
night through Tuesday should limit sustained winds to around 10
kt or less and seas to 2 ft or less.
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.CAR WATCHES/WARNINGS/ADVISORIES...
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ME...None.
MARINE...None.
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$$


Near Term...LaFlash
Short Term...Maloit
Long Term...Maloit
Aviation...LaFlash/Maloit
Marine...LaFlash/Maloit