Area Forecast Discussion Issued by NWS Caribou, ME
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000
FXUS61 KCAR 171024
AFDCAR
Area Forecast Discussion
National Weather Service Caribou ME
624 AM EDT Sun Mar 17 2024
.SYNOPSIS...
A warm front will lift across the region this morning. Low pressure
will track north of the area tonight. The low will remain to our
north Monday into Tuesday then dissipate as it tracks into the
Maritimes on Wednesday. Another weak low may form over the region on
Thursday.
&&
.NEAR TERM /THROUGH TONIGHT/...
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6:20 AM Update...Patchy precipitation has been moving across the
region including a small area of snow lifting across Eastern
Aroostook County early this morning. Further west, a band of
moderately heavier and more organized precipitation is
approaching Western Maine ahead of some upper level dynamic
support including lift out of the upper trough and divergence
aloft. Increased pops early this morning with the patchy
precipitation now moving through and adjusted temps a bit.
Otherwise, forecast remains on track. Expect the snow over the
northeast to mix with rain later this morning.
Low pressure over Southern Quebec will track into the St. Lawrence
Valley today as it brings slightly warmer air north. Moisture
pulling north across the region will get some lift from upper
level divergence over the east side of the trough bringing light
precipitation today, primarily this morning. Thicknesses are
very marginal, but suggest rain south, and a mix of rain and
snow across the northeast. Accumulating snow is most favored
over the higher elevations of the north where an inch or two is
possible through the morning. Precipitation will taper off to
scattered showers late today as the warm front lifts to our
north.
Surface low pressure will begin to weaken and track to our
north tonight as slightly drier and cooler air begins to work in
from the west beneath the low. Moisture pooled in the low, and
in the upper trough which will also be just to our north, may
bring some scattered snow showers over the north. To the south,
the air will become drier with some breaks in the overcast and
a gusty westerly breeze setting in. This system seems to lack a
well defined cold front following it, but does show a gradual
infiltration of cooler air beginning tonight.-- End Changed Discussion --
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
The FA will remain in cyclonic flow aloft in a low 500 millibar
height pattern as an upper trough in the northern Canadian
Maritimes extends into the region. The air mass aloft is cold,
but 925H temps are near to a little above average for this time
of year. As moisture and weak disturbances cross the area there
will be scattered showers, mainly across the north and western
high terrain. The showers would most likely be snow at night
and during the morning, and rain or snow in the afternoon.
Local minor accumulations are possible, but it is unlikely that
any one spot would get more than an inch or two of snow over the
duration of the short term. Lower shower chances toward Bangor
and the coast with downslope flow. Highs will mostly be in the
mid to upper 30s north with low to mid 40s toward the coast.
Lows Monday night will range from 25-30F north, and in the low
to mid 30s along the coast.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Briefly drier Tue night into Wed as the upper trough in the
Maritimes lifts out. Another trough from northern Canada digs into
New England Wed night into Thursday with colder air filtering into
the region. Most of the models indicate that a surface low develops
somewhere along the New England coast during this time, but there
are a lot of differences on where the development takes place. There
will likely be some snow showers that accompany the colder air, but
if the surface low develops close enough to the FA there could
be a steadier snow, especially if an inverted surface trough
extends back into Maine from the coast. Friday will likely
remain cold with a few more snow showers, especially across the
north. By Saturday model differences are significant and range
from high pressure building into the area to an area of low
pressure tracking up the coast with rain and snow. Forecaster
confidence is very low at this time for Saturday.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
NEAR TERM:
IFR conditions are expected in low clouds today with a possible
improvement to MVFR then VFR over southern sites late this
afternoon. Light SE wind becoming S then W this afternoon. VFR
conditions at southern sites and IFR to MVFR conditions across
the north are expected tonight. Light W wind.
SHORT TERM:
Mon: Predominately MVFR at the northern terminals with
local IFR in snow showers. MVFR to VFR at the Downeast terminals.
Wind west 10 to 15 knots.
Mon night & Tue: MVFR most of the time north, and predominately
VFR at the Downeast terminals. West wind 5 to 10 knots Mon
night, becoming NW 10 to 15 knots with a few higher gusts Tue.
Tue night and Wed: VFR Downeast and MVFR to VFR at the Aroostook
terminals. West wind 5 to 10 knots.
Wed night & Thu: MVFR with scatterd snow showers. Possible IFR if
there is a period of steadier snow. Wind shifting into the N around
5 knots Wed night, becoming NW 10 to 15 knots and gusty Thu.
&&
.MARINE...
NEAR TERM:
A SCA will continue today for S winds gusting up to 30 kt, with
a few gusts up to 35 kt over the offshore waters, and 25 kt
across the intracoastal waters. Winds will drop below SCA this
evening but may increase back to SCA over the offshore waters
late tonight in a gusty W wind. Seas will average around 6 to 8
ft today, subsiding to 5 ft tonight.
SHORT TERM:
Wind gusts are expected to be around 25 knots on the coastal
waters Monday with seas 4 to 5 ft, so borderline small craft
advisory conditions are expected. The wind and seas are expected
to be below SCA levels Mon night through Wed, although a few
gusts to 25 knots are possible Tue afternoon. SCA conditions
are likely on Thursday.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for
ANZ050>052.
&&
$$
Near Term...Bloomer
Short Term...CB
Long Term...CB
Aviation...Bloomer/CB
Marine...Bloomer/CB