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Area forecast discussion 
National Weather Service Caribou ME
1204 am EST Thursday Dec 25 2014

Synopsis...
strong low pressure will track west of New England through Thursday.
An occluded front will cross the state Thursday. High pressure
will then move in for Friday.

&&

Near term /through Thursday/...
midnight update...
all areas above freezing now, though many areas
not by much. Had to cool off temperatures for the next couple
hours based on observations. The one exception is along the coast,
where temperatures have soared into the lower to middle 50s. Except temperatures to
steadily rise through the night as the surface pressure gradient
becomes a bit more favorable for southerly winds to mix down and
warm things up.

A definite back edge to the steady rain is present on radar, with
rain presently lightening up in Bangor and Greenville and the back
edge advancing east. We have 100 percent precipitation chances through
the night, and opted to keep the 100 percent chances given that
drizzle will persist. Expect the steadier rain to move back in
around daybreak from the southwest. Did, however, remove heavy
at times wording from the forecast for tonight given that mostly
light rain and drizzle can be expected.

Previous discussion...
we did drop the remaining portion of the freezing rain advection. Most lctns over the
northwest and far NE were above fzg. Little if any ice accretion is being
obsvd with the few lctns at or below fzg...with forecast BUFKIT soundings
indicating a very large above fzg layer extending upwards to 750-800mb
over a near fzg layer extending only 100-200ft above the surface. Over the
next 2 to 3 hours...every location over the old advection area will be above fzg
at the surface. Otherwise...models are very consistent with forecast quantitative precipitation forecast
overnight into Thursday with rainfall...so no changes in earlier issued Flood
Watch.

Otherwise...with models forecasting a low level jet to reach 50 to 60 kts
intersecting SW to NE across the downeast coast beginning late
tonight we issued a wind advection for our coastal zones. Initially...
stronger wind gusts late tonight will be limited to the immediate coast
and especially higher terrain late tonight over the wind advection area...with
stronger wind gusts descending to lower terrain during the day Thursday
as low level lapse rates increase with the approach and passage of the cold
front. It is possible that wind gusts over the rest of the forecast area could
approach wind advection criteria later Thursday into Thursday evening...so we cannot rule
out expanding the wind advection nwrd during this tm.

Lastly...temperatures will initially slowly rise through the overnight...with
maximum temperatures Thursday morning into midday just ahead of the occluded front.
Temperatures will be coolest along the east slopes of higher terrain extending NE to SW
across the forecast area where very shallow low level cool air damming could hold
on. Following the passage of the cold front...temperatures should begin
to fall prior to sunset.

&&

Short term /Thursday night through Saturday/...
low pressure will continue to track across Labrador Thursday night
through Saturday as high pressure builds to our south. Expect
mainly cloudy skies north and partly cloudy skies across down east
areas with gusty west winds Thursday night and Friday. Expect
mostly to partly cloudy skies non Saturday. High temperatures
both Friday and Saturday will in the low to middle 30s and upper 30s
to lower 40s down east. Lows Thursday night will be in the lower 20s
north and upper 20s down east.

&&

Long term /Saturday night through Wednesday/...
at the start of the period the extended models are in good
agreement. A low with an associated front will be over the eastern
Great Lakes and southern Quebec. A high pressure ridge extends up the
eastern Seaboard into southern Maine. By Sun morning the low moves NE into eastern
Quebec/northwest Maine...the front extends SW across the western Maine
mountains...into southern New England. By sun evening the cold front moves
east of Maine. A low over northern Quebec...with its associated trough
extending through southern Quebec. By Monday morning the trough moves into
northern Maine. By Monday evening the Gem/European model (ecmwf) indicate a low moving north
along the NC coast...the GFS shows a low off the coast of SC and a
weak low over northern New York. Tuesday morning the GFS moves the low from over
northern New York to SW Nova Scotia. The Gem/European model (ecmwf) shows their lows in the
North Atlantic east of New Jersey. By Tuesday evening the GFS shows a high
pressure ridge built over Maine...with a frontal system extending
SW from Hudson Bay through the central Great Lakes. The European model (ecmwf) shows
a low south of Long Island with it precipitation band extending into central
Maine. Wednesday morning the ridge moves east...and the front pushes into
western Maine. The European model (ecmwf) deepens its low and moves it north to Nova
Scotia...with an occluded front wrapped around it extending into
northern Maine. The GFS moves the front east by Wednesday evening...builds a
high pressure ridge ac across Maine. The European model (ecmwf) moves the low to
Newfoundland...with wrap around precipitation extending back across Maine.
By the of the period...both models indicate higher pressure across
the area...with a front approaching from the northwest.

Loaded the superblend. Loaded nawave 4 for seas for the coastal
waters. Added 15 percent to winds for gusts over land...30 percent
for gusts over the coastal waters.

&&

Aviation /06z Thursday through Monday/...
near term: generally IFR tonight in rain, drizzle, low clouds, and
fog. Local MVFR, but predominantly we will be seeing IFR through
the night. Significant wind shear at most locations.

Cold front moves through Christmas day with conditions improving
to VFR most places behind the front.

Short term: mainly VFR Thursday night through Saturday. IFR/MVFR
is possible later Saturday night and Sunday in snow or snow
showers. VFR with possible MVFR ceilings across the north Sunday
night and Monday.

&&

Marine...
near term: Gale Warning in effect for the waters through Thursday
evening. Winds and waves, however, have been slow to come up so
far, and have lowered them a bit for the rest of tonight with the
midnight update. Still expect seas and winds to increase later
tonight, though.

Short term: gale force winds are expected into early Thursday
night. Small craft conditions can then be expected on Friday.

&&

Hydrology...
heavy rainfall ranging from 1.25 to 2.00 inches on top of a
melting snowpack will bring the potential for stream and river
flooding for interior downeast and central areas...while further
north...localized flooding from ice jams is possible.

&&

Tides/coastal flooding...
with a strong srly wind fetch and building WV heights expeceted with the
just after mdngt hi tide tonight...we did issue a coastal flood
statement between 10 PM and 2 am for the possibility of WV wash-
up above the maximum astro tide mark...which could affect a few low
lying roads along the downeast coastline.

&&

Climate...
record high temperatures are likely Christmas day. The
current forecast high for Bangor is 54f. This is well above the
record high of 51f...set in 2003. At Caribou...the record high is
48f, also set in 2003. We are currently forecasting a high of near
48f at Caribou.

&&

Car watches/warnings/advisories...
ME...Flood Watch through Friday morning for mez001>006-010-011-
015>017-031-032.
Wind Advisory until 4 PM EST Thursday for mez029-030.
Marine...Gale Warning until 1 am EST Friday for anz050>052.

&&

$$

Near term...foisy/vjn
short term...duda
long term...Norton
aviation...foisy/duda
marine...foisy/duda
hydrology...vjn
tides/coastal flooding...vjn
climate...vjn

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