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Area forecast discussion 
National Weather Service Caribou ME
749 am EDT sun Oct 23 2016

strong low pressure will be positioned just to our north today,
resulting in gusty winds and much colder temperatures. The low
will slowly lift northward tonight through Tuesday, but winds
will remain on the breezy side and temperatures will stay below
normal through Tuesday.


Near term /through tonight/...
8 am update...the Wind Advisory was extended to central and
downeast areas. Cold advection, deep mixing and a tight gradient
will likely result in some strong wind gusts up to 40 mph downeast
during the midday and afternoon.

635 am significant changes were needed this morning.
Showers have been increasing in coverage this morning, particuarly
across the north. Likely pops still look good there, with
scattered wording elsewhere through early afternoon. Temperatures
in the North Woods are in the MD and upper 30s, so would
anticipate some snow mixing in, especially over the higher
terrain. Winds have dropped off over the past few hours, but
expect they'll pick back up as we head through the morning. Did
make some adjustments to temps, winds, and pops to bring them into
line with current conditions. Overall the forecast remains in good

Previous discussion...gusty winds are the concern for today and
tonight. A Wind Advisory has been issued for much of northern
Maine for this afternoon and evening. This may potentially need to
be expanded further south toward the coast.

A 980mb low will slowly spin over southern Quebec today, very slowly
shifting northward as it does so. The 00z model runs seem to have
initialized this feature well, with much of the guidance within
1mb. Current progs indicate that the low will hold its strength or
even deepen a bit more through the day today. Meanwhile, high
pressure will build across the southeastern US, leading to a
tightening pressure gradient and gusty winds. An 40-50 kt jet at
850mb will move across northern Maine this afternoon and evening,
helping to increase the wind gust potential, particularly across
the higher terrain of the North Woods. The one mitigating factor
will be cloud cover which will limit mixing to some extent, but
gusts of 45 mph are possible; any breaks of sunshine could result
in gusts closer to 50 mph. The jet will peak over the area late
this afternoon in the 20z-03z (4pm to 11pm) timeframe, but mixing
will lessen once the sun GOES down. Have therefore issued a Wind
Advisory for all of our northwestern zones, particularly areas
along and north of a Presque Isle to Greenville line. Effective
time is 11 am to 8 PM as this will encompass the peak gusts.
Downeast Maine, including the Bangor region, will be on the edge
of the jet Max, so potential peak gusts look to only be 30-35 mph.
However, these areas have a better chance of seeing sunshine this
afternoon. Also, with leaves still on the trees, branches may
break resulting in power outages. Will go with a strongly worded
hazardous weather outlook for now, but the day crew will need to
watch trends closely and may need to expand the advisory further
south. Other than the wind...the other item of note will be the
temperatures, which will be a good 15-20 degrees colder than
yesterday. Combined with the gusty winds, it will definitely feel
like fall today. Scattered to numerous showers are expected to
redevelop today as we get some heating, mainly over the north and
west. Some of these showers may even fall as a rain/snow mix over
the highest terrain the far north and west.

For tonight...winds will abate somewhat as the low pulls away from
the Pine Tree state and mixing decreases due to loss of daytime
heating. It'll still be breezy, though, with gusts of 20-30 mph.
Shower activity will wane as well with the loss of heating.
Overnight lows will range from the upper 20s in the upper St John
valley to the lower and mid 30s downeast.


Short term /Monday through Tuesday/...
quasi-stationary upper low pres near Labrador will keep cldnss and
ocnl rn/sn shwrs to spcly nrn ptns of the forecast area Mon thru Wed. Sn
shwrs will be the dominate precip type msly late at ngt and morn
on Tue and Wed spcly across the hi trrn, with the best potential
for any accumulating snfl will be late Mon ngt into Tue morn
across the far N, again spcly across higher trrn where temps will
be a couple of degs cooler. Shwrs will slowly dissipate durg the
day Wed as as east-west upper trof left ovr from the departing upper low
finally moves out to the east.

Hi temps will be sig below avg for late Oct with Mon particularly
brisk with gradually less wind for Tue and Wed. Ovrngt lows will
also become progressively cooler each morn as colder llvl air
slowly invades the fa, but not much below avg due to cld cvr and


Long term /Tuesday night through Saturday/...
with clrg skies and diminishing winds withe the apch of strong
Canadian sfc hi pres, Wed ngt will likely be the coldest ngt of
the fall season so far, with coldest ovrngt lows in the teens ovr
normally coldest northwest Vly lctns. Thu looks to be msly sunny and
more pleasant with lgt winds, but still below avg temps.

Models have now come into much better agreement with the next sfc
low and associated S/WV system apchg our region from the great
lks later Thu ngt thru Fri. The majority of the models give the
region arnd a half inch of total event qpf, with steady rnfl
tapering to sct shwrs Fri ngt. Depending if precip begins durg the
late ngt hrs Thu ngt or early Fri morn, precip may begin as a
brief mix of lgt rn and sn across the north with little if any in the
way of sn accumulation, but the vast majority of this event looks
to be rain at this point. Sat looks to be cool and drier, but with
lingering SC cld cvr across the north.


Aviation /12z Sunday through Thursday/...
near term: widespread MVFR with occasional IFR conditions are
expected much of today as low pressure moves north of the region.
Ceilings will likely fluctuate in the 900-1800 ft range through
the period. The northern terminals have the best chance of seeing
IFR as showers will once again develop in these areas today.
Conditions will improve late this afternoon into the evening as
the sun GOES down and showers wane and clouds begin to lift.
Expect all terminals will be VFR by 00z Monday. The other concern
is gusty winds, which will turn from south to west through the
day. Gusts of 25 to 35 kt will be possible 15z-00z today. These
should lessen a bit after 00z, but 20-25 kt gusts are still

Short to long term: MVFR bkn-ovc SC clgs and ocnly vsbys in rn/sn
shwrs xpctd across nrn taf sites Mon thru Wed while downeast
sites hold msly low VFR. All sites becoming unlmtd VFR Wed ngt
with clrg skies...contg thru Thu.


near term: the Gale Warning remains in effect through today into
tonight. Winds are currently 25-30 kt with gusts of 35-40 kt and
this will be the trend through the day. Seas are 11-14 ft at this
hour, but these will subside to around 10 ft by this evening as
winds turn more westerly. Winds will subside a bit as well, so the
Gale Warning should be able to be converted over to a Small Craft
Advisory this evening.

Short to long term: a Small Craft Advisory pd will be needed Mon aft the ending of
the glw, possibly lasting into Tue morn for outer mzs050-051
while inner Bay/Harbor mz052 will likely need a shorter Small Craft Advisory
possibly into Mon eve. Aft a break later Tue thru Thu. Kept close
to ww3 WV guidance for fcst WV hts ovr this ptn of the fcst.


Car watches/warnings/advisories...
ME...Wind Advisory from 11 am this morning to 8 PM EDT this evening
for mez001>006-010-011-015>017-029>032.
Marine...Gale Warning until 8 PM EDT this evening for anz052.
Gale Warning until midnight EDT tonight for anz050-051.



Near term...Hastings/mcb
short term...vjn
long term...vjn

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