Area Forecast Discussion
Issued by NWS Caribou, ME-- Highlight Changed Discussion --
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FXUS61 KCAR 081028
Area Forecast Discussion
National Weather Service Caribou ME
528 AM EST Thu Dec 8 2016
An upper level trof will approach the region from the west today
and cross the area tonight. Much colder air is expected to
overspread the region on Friday and remain through the weekend.
.NEAR TERM /THROUGH TONIGHT/...
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Minor tweaks to hrly temps this am no other changes.
An upper level low near James Bay will move east
through Quebec Province today. Short wave energy in advance of the
upper trof will bring the chance of a snow shower to northern and
central areas today and rain or snow showers to downeast areas.
Otherwise expect mainly cloudy skies today. It will be a bit
milder with highs ranging from around 30 degrees across the north
and low to mid 30s across central and downeast.
The upper trof will slide east across the forecast area
tonight. Colder air will begin to move into the region tonight.
As it does so, a few snow showers will be possible especially
across northern and central areas. There could be a few heavier
snow showers across northern Aroostook late tonight with the
colder air coming across the open St. Lawrence. Couldn`t rule out
some localized snow accumulations overnight across the north in
any heavier snow showers. Lows tonight will range from the upper
teens to near 20 degrees across the north and lower 20s downeast.
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.SHORT TERM /FRIDAY THROUGH SUNDAY/...
Models still in relative agreement regarding the potential of sn
shwrs/sqls across msly the N hlf of the FA with the arrival of
colder arctic air with St Lawrence seaway sn band streamers likely
contg ovr the N into Fri ngt. Colder drier arctic air should then
shut down sn shwrs to sct flurries across the N by Sat. During
both Fri and Sat, winds will be brisk with below zero wind chills
spcly across the N and Cntrl ptns of the FA and spcly Fri ngt into
Sat morn. Hi temps Sat will be sig below seasonal avgs.
Winds should diminish late Sat ngt and with some clrg spcly ovr NW
vlys, some lctns here could fall below zero with single digits abv
zero further SE and 10 to 15 alg the Downeast coast by erly Sun
morn. Sun will begin fair, with increasing cldnss by aftn as low
pres from the Midwest begins to apch. Hi temps Sun should return
to similar values as Sat, but with much less wind.
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
Models are neither in run to run or model to model comparison
agreement with the low pres system xpctd to track from the Midwest
toward the Srn Gulf of ME or open N Atlc Sun ngt and Mon. Of the
latest 00z dtmnstc model suite of models, the CanGem was the
furthest N and most intense with the low Mon into Mon ngt,
suggesting sn adv or even wntr stm wrng snfl criteria and even
enough llvl warm air to mix or chg sn to rn alg the immediate
coast durg the height of the event Mon aftn into Mon eve.
Unfortunately, the 00z ECMWF run was opposed to it`s prior 12z
run, and is much further s with the track of the sfc low. Similar
to most recent prior model runs, the 00z GFS run is again
relatively weak with a srn track with alg with the ECMWF, would
only graze or even miss far Nrn ptns of the FA with any snfl.
Even the 00z GFS ensm was further S than the 12z ensm track of
the sfc low, but did imply some snfl for even far Nrn ptns of the
FA. This scenario was also mirrored by the 00z CFS model output.
So for now, we will keep hi chc pops of sn for Nrn Me cntrd on Mon
and likely PoPs for Cntrl and Downeast ptns of the region and will
wait for more model consensus before committing either way with
PoPs and implied liq equiv precip/snfl for the region. Aftwrds,
there is even more uncertainty, with some models like the GFS, GFS
ensm, and CFS bringing a potential sig precip event to the region
midweek ahead of potentially the coldest outbreak of arctic air to
our region slated for late next week, while the ECMWF just brings
sn shwrs ahead of the arctic front. Given track uncertainties
with Mon`s event, needless to say there is even more uncertainty
for any event for mid next week. Temps Sun thru Wed looks to be
msly below avg, but not as cold as this weekend.
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
NEAR TERM: Variable flight conditions are expected this morning
with mainly VFR conditions but local MVFR/IFR in patchy freezing
fog and low ceilings. Scattered snow showers are possible across
the northern terminals today and rain/snow showers downeast with
lcl MVFR conditions expected. Expect MVFR in sct snow showers
across the north tonight with VFR downeast.
SHORT TO LONG TERM: MVFR clgs xpctd across the N and low VFR clgs
Cntrl Downeast thru Fri eve, then VFR all sites late Fri ngt thru
Sun eve. Vsbys briefly IFR attms across the N Fri and Fri eve and
MVFR late Fri ngt in sn shwrs/sn sqls and MVFR Cntrl and Downeast
Fri into Fri eve. All sites then VFR Sat and Sun. Clgs and vsbys
gradually lower to MVFR from SW to NE ovrngt Sun and then to IFR
on Mon in sn.
NEAR TERM: Winds/seas will remain below small craft advisory levels
through early afternoon but then begin to increase in advance of
the approaching trof from the west. Winds/seas are expected to
increase to small craft advisory levels this evening and continue
SHORT TO LONG TERM: Will cont with SCA/gale watch Fri into erly
Sat morn for cold advcn NW winds...with SCA`s likely to be needed
again late Sat morn into Sat ngt. After a break Sun into Sun ngt,
the next chc for marine wind hdlns will be Mon into Tue depending
on the track of low pres into the Srn Gulf of ME or the open N
Atlc. Kept close to WW3 wv guidance for fcst wv hts thru these
ptns of the fcst.
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MARINE...Small Craft Advisory from 7 PM this evening to 4 PM EST Friday
Gale Watch from Friday afternoon through Saturday morning for
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