Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
442 PM EST Wednesday Nov 25 2015
strong high pressure over the region will slowly move east of the
area through Thanksgiving day. A cold front will reach northern
Maine later Friday...then cross the region Friday night. High
pressure will build across the region through the weekend.
Near term /through Thursday/...
a very strong high pressure system centered over the area will
continue to strengthen to around 1050mb as it moves east into the
Canadian Maritimes tonight. This will produce continued clear
skies and quick radiational cooling through the first half of the
night. Lows will drop off towards the upper teens in the north
half of the forecast area and into the middle to upper 20s for Bangor
and downeast. Later in the night as the high moves east...a
strengthening pressure gradient and resulting strong southerly
flow will advect maritime moisture northward under an impressive
subsidence inversion. The clouds will spread across most of the
forecast area after midnight and remain all of Thanksgiving. The
clouds will be accompanied by warming temperatures. Lows tonight
will occur well before dawn and start rising later in the night.
The temperatures will continue rising through Thanksgiving towards
the low to middle 40s. The moisture advection and markedly increasing
dew points should be enough to generate generate some drizzle and
upslope fog...mostly in the upslope zone from southern Piscataquis
towards Mars Hill. The biggest concern would be the threat of
patchy freezing drizzle late tonight and early Thanksgiving
morning. This threat would appear to be north of Bangor and the
downeast zones. Temperatures are forecast to be above 32f across
most of the area by 9am Thanksgiving. South winds will also be
rather gusty tomorrow afternoon with gusts to 25 miles per hour...especially
near the coast.
Short term /Thursday night through Saturday/...
high pressure will be ridged south of the region with a cold
front extending from the Great Lakes across Quebec province
Thursday night. Skies will be mostly cloudy across the region
Thursday night. With increasing low level moisture...could also
have patchy drizzle across the forecast area. Could also have a
slight chance of rain showers late across northern areas. The cold
front will reach northern Maine later Friday with a chance of rain
showers in the morning with a steadier rain developing during the
afternoon. Rain chances will begin to increase across
central/downeast portions of the forecast area later in the
afternoon. The cold front will cross the region Friday night with
rain in advance of the front. The rain will mix with...or change
to...snow across northern and central portions of the forecast
area in the wake of the cold front. Light snow
accumulations...less than inch...are possible across northern
portions of the forecast area before precipitation ends. High
pressure will begin to build across the forecast area later Friday
night. High pressure then builds across the region Saturday with
partly/mostly sunny skies across northern areas and decreasing
clouds downeast. Temperatures will be at above normal levels
Friday...with near normal level temperatures Saturday.
Long term /Saturday night through Wednesday/...
eastern Maine will be in a northwest flow aloft into Monday. The
12z GFS does have a fast moving shortwave grazing The Crown of
Maine on Sunday. The model consensus keeps things dry...however
would not be surprised if a chance of snow showers probability of precipitation up in
later forecasts. Temperatures will be slightly above normal on
Sunday and slightly below normal on Monday.
A short wave ridge passes over the region on Tuesday for dry and
warmer weather. A strong upper trough approaches from the Great
Lakes next Wednesday. Southwest flow ahead of a cold front should
make this a rain or snow changing to rain event for most locations.
Aviation /21z Wednesday through Monday/...
near term: VFR conditions continue through late tonight. MVFR
ceilings arrive after midnight...and are expected to drop to IFR
north of mlt and hul early Thanksgiving. Visible could deteriorate in
drizzle at times late tonight through Thanksgiving. This drizzle
could be frozen until around 14z north of bgr. Low level wind
shear is also possible late tonight and Thanksgiving morning with
southwest winds at fl020 near 40 to 45 kts.
Short term: MVFR to LIFR conditions are expected across the
region Thursday night into Friday night. Conditions will begin to
improve later Friday night. Occasional MVFR conditions are
possible early Saturday downeast. Otherwise...generally expect VFR
conditions across the region Saturday through Monday.
near term: fairly calm conditions will give way to an Small Craft Advisory by late
Thanksgiving morning with wind gusts hitting 25 kts and seas
climbing towards 5 feet.
Short term: Small Craft Advisory conditions are expected Thursday
night through Saturday. Visibilities could be reduced in rain
Marine...Small Craft Advisory from 11 am Thursday to 7 am EST Friday