Area Forecast Discussion
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FXUS61 KCAR 242237
Area Forecast Discussion
National Weather Service Caribou ME
637 PM EDT WED AUG 24 2016
High pressure will remain to the south through Thursday. A cold
front will cross the region Friday. High pressure builds Saturday
.NEAR TERM /THROUGH THURSDAY/...
635 PM update. Minor adjustments to the hrly temps, and SKYCON
otherwise previous forecast remains on track.
Ridging will build more into the area this evening, likely
closing off any further chance for showers this evening. Mostly
clear skies are expected overnight, though clouds will creep in
from the west before sunrise. It will remain mild overnight,
thanks to S-SW`ly winds keeping dewpts elevated and allowing for
warm advection, as well.
A weak disturbance in the form of a very shallow 500mb trof moving
thru the ridge will cross the CWA Thurs afternoon. This will bring
the risk for some shwrs and perhaps a stray t-storm to the
northern areas, mainly north of a Greenville-Houlton line. Kept
POPs limited to Chance and kept QPF fairly low due to the likely
isolated nature of the precip and the continuing wide spread in
model solutions for QPF Thurs PM.
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
Thursday night will be warm with a thermal ridge along and a
southwest surface flow. Have gone above guidance for lows in the
mid to upper 60s and high humidity. With an approaching frontal
system and the potential instability on Thursday night, have gone
with a chance of showers and a slight chance of thunderstorms for
much of the forecast area. Patchy fog and low clouds will tend to
develop later in the night with an onshore flow and continue into
early morning. The fog and low clouds will persist longer on
Friday along the coast. Will continue the chance of showers and
thunderstorms on Friday with the approaching cold front. The
chances of any stronger thunderstorms remains in question due to
the timing of the surface front and the upper level shortwave
ejecting from the Great Lakes region. Shear is impressive, but
CAPE is not. The best combination of CAPE and shear currently
appears to be in northeast Aroostook County in the afternoon with
the cold frontal passage, but confidence is not high enough to
add enhanced wording at this time. Once the front is through, high
pressure builds Friday night and Saturday with cooler temperatures
and lower humidity.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
High pressure centered over the area will produce a relatively
chilly Saturday night. Can`t rule out readings near 40F in the
Allagash. Most the forecast area will have lows in the 40s except
Bangor and the Down East region where low 50s are anticipated.
Pleasant highs in the 70s with low humidity continues Sunday. A
frontal system crosses Sunday night into Monday with timing still
uncertain. Due to the timing uncertainties, did not specify
thunderstorms for Monday afternoon. Regardless of the model, high
pressure is expected to return Monday night into Tuesday night.
Another front is possible towards Wednesday with a chance of
showers towards the Crown of Maine.
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
NEAR TERM: Expect mainly VFR conditions thru Thurs, with two
exceptions. One will be the possibility for patchy fog in northern
areas tonight (KHUL thru KFVE) - however confidence in this
occurring wasn`t high enough to include it in grids or TAFs. The
second possible reduction in category will be around any possible
shwrs, again mainly a risk for northern terminals.
SHORT TERM: Most of the period will be VFR. The exceptions will
be later Thursday night into Friday morning when IFR cigs are
possible. These IFR cigs may persist much of the day towards BHB.
Thunderstorms are another concern Thursday night and Friday.
Patchy valley fog is possible towards sunrise on Sunday morning.
NEAR TERM: Winds and seas will both remain below SCA thresholds
for tonight into early Thurs. However, wind gusts and seas are
both forecast to build close to SCA levels Thurs afternoon and
evening, but at this time it is borderline, so will leave it to
later shifts to make a call on an advisory. Onshore winds could
lead to some patchy fog later tonight, which could hang on through
the day Thurs.
SHORT TERM: Fog will develop Thursday night and continue Friday.
Winds will be near 20kts on Thursday night with seas in the 4 to 5
ft range...but decrease Friday into Saturday. A thunderstorm or
two is possible Friday afternoon.