Area Forecast Discussion
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FXUS61 KGYX 302249 AAA
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
549 PM EST Wed Nov 30 2016
Low pressure will track from the Great Lakes into Quebec tonight
as a secondary low develops over the mid Atlantic region. This
secondary low will track along the New england coast late tonight
and Thursday drawing colder air into the mountains and adjacent
foothills, changing a snow and rain mix there over to wet snow.
Precipitation will taper off on Thursday as the low exits into the
maritimes. Somewhat cooler and drier air will arrive late Thursday
and Friday with temperatures cooling as we move into the weekend.
.NEAR TERM /THROUGH THURSDAY/...
547 PM Update: Going forecast in good shape. Input latest
observations and adjusted PoPs to slow northward progression of
steadier precipitation just a tad based on latest regional radar
composite. No significant changes to ptype thinking at this
juncture. Will reassess after 00Z RAOB comes in over the next 1-2
At 19z...a 1028 millibar high was centered over eastern Canada
and was nosing southward into eastern New England. A complex area
of low pressure was over the Great Lakes with a wavy frontal
boundary extending through the DELMARVA region. NWS doppler radar
mosaic showed an extensive area of precipitation along and to the
south of the frontal system. Colder and drier air was draining
south and west from northern Maine with the canadian high and will
set the stage for wintry precipitation across portions of the
mountains and foothills as precipitation spreads northward and the
atmospheric column cools to at or below 0c. In additional...the
developing coastal low will also help to draw even cooler air
southward into this area late tonight and Thursday morning as it
races northeast along or just offshore. There will be large
variations in snow and sleet amounts as we deal with mixing as
well as elevation issues. Outside of the mountains and
foothills...mainly a cold rain event is expected tonight.
.SHORT TERM /THURSDAY NIGHT/...
Precipitation will taper from southwest to northeast on Thursday
following the passage of the coastal low and occluded front.
Precipitation will linger the longest along the International
border as well as eastern zones before ending during the
afternoon. Some drier air will work into southern New Hampshire
and southwest coastal Maine behind the departing low...with
partial sunshine and westerly flow allowing temperatures to warm
into the lower 50s. Highs elsewhere mainly in the 40s...with 30s
across the northern mountains.
Breezy and cold Thursday night with mainly clear skies for
southern New Hampshire and much of the coastal plain in downslope
flow. Elsewhere...cyclonic flow and upslope with a few mainly
mountain snow showers. Lows will be in the 30s.
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
By daytime Friday cold air has already begun shifting into the
Great Lakes region and New England. Additional snow showers are
likely over the mountains with rain showers less likely as a
surface trough moving offshore. Reinforcing cold air arrives
Friday night with 850mb temperatures dropping to near -10 degrees
C. Additional snow accumulations are likely Saturday on northward
facing slopes as WNW winds increase aloft and at the surface.
Winds will be strong and gusty from the NW on Saturday. This will
help clouds clear out over the coastal plain gradually. Sunday
through Tuesday cold high pressure from Canada builds in.
Temperatures early in the work week will be around the mid
20s/lower 30s north to upper 30s/near 40 for highs. Overnight it
looks like there will be at least a few chilly nights: Saturday,
Sunday, and Monday with readings in the tens and teens across the
mountains and 20s elsewhere. There will be a gradual warm up for
mid week for southern NH and on the coast with warm air advection
trying to nudge in ahead of the next wave arriving from the
central CONUS. However...during this time cold air damming
sharpens as it did earlier this week and isentropic lift
increases over the cold dome at the surface. This may bring mixed
precipitation and dense fog/freezing fog conditions to areas away
from the coast.
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Short Term /Through Thursday night/...Conds lowering to IFR with
areas of LIFR in RA and Fog with RA/SN transitioning to SN/PL in
the Mtns and foothills. Improving to VFR from SW to NE by Thu Aft
with lingering MVFR in MTN -shsn.
Long Term...RKD, AUG, and PWM will see a chance of -SHRA through
mainly Friday. HIE may continue to experience -SHSN through
Saturday. NW winds will be gusty especially Saturday afternoon
into Sunday morning. VFR returns to all TAF sites Sunday with
additional rain and snow showers moving in from the SW late Sunday
Short Term /Through Thursday night/...Winds and seas build
quickly ahead of the coastal low overnight and it`s likely we`ll
see a period of Gales over our eastern waters including Penobscot
Bay late tonight and Thursday morning immediately ahead of the
coastal low. behind it...westerly flow should reach small craft.
Long Term...Winds will most likely reach SCA criteria on the outer
waters and bays Saturday afternoon into early Sunday.
ME...Winter Weather Advisory until 1 PM EST Thursday for MEZ008-013-
Winter Storm Warning until 3 PM EST Thursday for MEZ009.
MARINE...Small Craft Advisory until 11 AM EST Thursday for ANZ153-154.
Gale Warning until 11 AM EST Thursday for ANZ150>152.