Area Forecast Discussion
Issued by NWS Caribou, ME-- Highlight Changed Discussion --
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FXUS61 KCAR 261626
Area Forecast Discussion
National Weather Service Caribou ME
1226 PM EDT THU MAY 26 2016
High pressure builds north of the area today. A warm front will
move north across the area Friday and a cold front moves through
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --1225 PM update...
Hv lowered temps by 5-8 degrees acrs nern zones tda as stratus
conts to hang tuff. Areas that are seeing full sun hv risen into
the 70s as of 16z as opposed to 50s acrs Aroostook. No other chgs
needed at this time. Still expecting clds to slowly erode by mid-
aftn bfr clds mv back in fm the east this evng.
Prev discussion blo...
Low pressure currently over the Maritimes will continue to move
away to the northeast during the day today as high pressure builds
in from the north behind the departing low. High pressure will
then crest over the State during the early afternoon. The high
will then move to the east of New England later today and tonight
with clouds moving in from the southwest in the return flow behind
the departing high. Showers will then spread across the region
from the southwest later tonight.
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.SHORT TERM /FRIDAY THROUGH SATURDAY/...
A progressive pattern has settled into place and will continue
into the long term.
Wet conditions for Friday w/showers as a warm front lifts n across
the area. It will be an increasingly humid day w/dewpoints forecast
to rise well into the 50s. Showers will exit the region by Friday
afternoon as the region gets into a pseud-warm sector. Plenty of
llvl moisture remains into the afternoon w/some breaks possible.
This would allow temps to rise well into the 60s after a sluggish
start to day w/a sse wind and low clouds. Any instability is
limited above 4k ft(400 joules)across northern and central areas.
PWATS just under 1.00 inch w/decent 0-6km shear of 25 kts. The
negative factor is the large area of dry air above 850mbs which
would inhibit growth. Given this, decided to keep the mention of
thunder out of the forecast for Friday.
There is some discrepancy come Friday night as the 00Z NAM shows
a cold front sliding se across the region and brings a good area
of precip w/it. The ECMWF is similar w/bringing an area of precip
across the region but not nearly as heavy. The GFS is slower w/the
front and less active. NAM soundings are explosive w/SB CAPE OF
1000+ joules Friday evening and very unstable especially across
northern and western Maine. The GFS is not as unstable and it
much drier aloft. The NAM historically has been overdoing its llvl
moisture. Confidence is not high enough go any more than isolated
tstms. Therefore, kept 30-40% chance for shower and isolated
storms. Temperatures Friday night will stay in the 50s. The cold
front is forecast to stall across the downeast region on Saturday
w/high pres sliding across northern Maine from Canada. The
atmosphere across the downeast region will be very unstable w/sb
capes progged to be 1500+ joules. PWATS of 1.2+ inches w/0-6km
shear of 25 kts. So, the potential is there for tstms in the
afternoon into the early evening, plus flow is wnw w/no inhibitor
from the Gulf of Maine. Afternoon temps will warm to around 80F
in the downeast region. Lacking feature is that the low/mid level
lapse rates are progged to be around 6.0 c/km deep llvl moisture
lacking. This could change w/the later model runs. Decided to add
thunder after collaborating w/GYX but left out enhanced wording.
Daycrew can assess this further today.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As stated above, pattern remains progressive through this term.
Showers and any tstms will be diminishing and moving se Saturday
night per the GFS while the ECMWF brings the cold front back as a
warm front along w/a decent slug of precip lifting across
northern areas by Sunday morning. Since confidence is not high on
this setup, decided to take a consensus blend showing 30-40% chance
for showers across downeast and sw areas Saturday night and this
area lifting ne Sunday into Sunday night. Temps are forecast to
warm Sunday night w/the CWA getting into the warm sector on
Monday. The ECMWF and GFS are pretty close on this setup w/a sw
flow developing ahead of the apchg cold front. Showers and
possible tstm on Monday w/drier conditions expected for Tuesday
as the cold front clears the region.
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
NEAR TERM: Expect VFR/MVFR conditions this morning then VFR
conditions later this morning through tonight.
SHORT TERM: IFR/MVFR for the terminals on Friday w/improvement to
vfr mainly for the BGR site. VFR looks be in the offing for all
terminals Friday evening w/the exception of BHB as a s flow could
keep IFR conditions. IFR/MVFR returns later Friday night into
Saturday morning ahead of a cold front dropping s into the
downeast region. Conditions are expected to improve to VFR for
all terminals by midday Saturday.
NEAR TERM: For sustained winds have used the GFS20. For waves:
Currently the primary wave system is incoming long period swell
from the southeast. The Wave Watch III has a good handle on this
wave system with the forecast closely matching observations from
44027. With light winds expected through tonight expect this long
period wave system to dominate through tonight with wave heights
expected to subside by a foot or so later today and this evening.
SHORT TERM: No headlines foreseen through the period. Waves are
forecast to build to around 4 ft by Monday as ssw flow takes hold.
Sustained winds are forecast to remain below 20 kts through the