Area Forecast Discussion
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FXUS61 KCAR 050015
Area Forecast Discussion
National Weather Service Caribou ME
715 PM EST Sun Dec 4 2016
High pressure will cross the region tonight then move to the east
Monday morning. A weak trough of low pressure will move across
the area Monday afternoon into Monday evening. High pressure will
return on Tuesday.
.NEAR TERM /THROUGH MONDAY/...
High pressure will cross the region tonight with mostly clear
skies and cold temperatures. Could also have patchy freezing fog
overnight, particularly along river valleys and across the north
where the deeper snowpack exists. This will be the coldest night
of the season with low temperatures generally ranging through the
single digits above zero north, to the mid to upper teens across
the Bangor and Downeast regions. Have updated the forecast to
adjust for current conditions along with overnight temperatures
and cloud cover.
A weak upper level trough approaching the area on Monday will
bring increasing clouds. A small surface low will develop offshore
and an inverted trough extending onto the coast may produce a
period of light snow along the coast late in the day. Otherwise,
Monday afternoon will be mostly cloudy and cold across the area.
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
A weak upper trough will cross the area Monday night. This trough
may produce a Norlun trough somewhere around the Hancock County
coast Monday evening with snow showers. Have gone with chance pops
for snow showers Monday for Down East zones. Pops and clouds
diminish as the night progresses and focus turns towards northern
Aroostook County where there`s the risk of freezing fog and
temperatures around 10F. A few of the colder valleys could even
drop towards zero with the fresh snowpack, but it`s going to be a
very steep subsidence inversion and it`s not a real dry Arctic air
mass. Thus, fog may form before temperatures drop much below 10F.
Lows for Bangor and the Down East region will be in the upper
teens to lower 20s. On Tuesday, high pressure dominates with highs
in the mid 20s north and low to mid 30s south. The biggest
question will be the evolution of any fog into low clouds north of
Houlton on Tuesday. The strong subsidence inversion and available
low level moisture cast strong doubts on the prospect of sunshine
in these northern zones. These clouds will likely persist north of
Houlton Tuesday night into Wednesday. Any breaks in the clouds
could produce another round of freezing fog Tuesday night. In
terms of low temperatures Tuesday night, went with a consensus
blend, but the clouds could mean an upward adjustment will be
necessary. High clouds will also increase Tuesday night into
Wednesday...meaning all zones will have mostly cloudy skies. Highs
will be a couple of degrees warmer on Wednesday. Went with slight
chance pops on Wednesday due to a rapidly decaying shortwave
rotating around an upper low in Ontario. Can`t see much more an a
hundredth or two of QPF in the worst case.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
High pressure moves east of CWA early Thursday with a short wave
approaching from the Great Lakes. This is a fairly quick mover
so currently expect only a few inches of snow across the CWA
with rain along the coast. A mid-Atlantic low then develops and
drifts northeast but bulk of current model runs show this system
remaining well offshore and moving rapidly northeast. The mean of
the ensemble still shows a great deal of variability in the
long term models with the European as the current outlier
predicting significant snowfall...so opt to stick solely with
chance pops Thursday...with rain along the Downeast coast and snow
elsewhere...with pops diminishing through the end of the period.
Temperatures should remain slightly above normal through Friday
with cold air moving in behind the secondary mid-Atlantic low
through the end period bringing temps to below normal.
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
NEAR TERM: Variable conditions could occur with any patchy
freezing fog overnight. Otherwise, generally expect VFR conditions
across the region overnight into Monday morning. Occasional MVFR
conditions could begin to develop across northern areas later
Monday afternoon. MVFR, with occasional IFR, conditions are
expected to develop across the Bangor and Downeast regions later
Monday afternoon with light snow.
SHORT TERM: BGR will likely be VFR until Wednesday. BHB might be
temporarily IFR in snow showers Monday evening, but will then be
VFR until Wednesday. Terminals north of HUL could experience
freezing fog and LIFR later Monday night into early Tuesday
morning. From Tuesday morning into Thursday, there is a strong
risk of low cigs varying between IFR and low MVFR for these
NEAR TERM: Winds/seas are expected to remain below small craft
advisory levels tonight through Monday. Visibilities could be
reduced in rain/snow Monday afternoon.
SHORT TERM: Snow showers could be an issue around the Hancock
County coast on Monday evening. Otherwise, no significant weather
is anticipated until Thursday night when an SCA or even a gale is