Area Forecast Discussion
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FXUS61 KCAR 221647
Area Forecast Discussion
National Weather Service Caribou ME
1247 PM EDT Thu Sep 22 2016
High pres will continue to bring fair conditions into today. Low
pres from central Canada will move across the region tonight into
Friday bringing rain to the region. Colder air is expected for the
first full weekend of Autumn as Canadian high pressure builds in
behind the low.
.NEAR TERM /THROUGH TONIGHT/...
1245 PM update...No significant changes were needed with this
update. The cold front has moved offshore, and mid and high clouds
are starting to stream in ahead of the approaching low. Rain still
looks possible across the far north as we head toward late
afternoon. Have made some tweaks to sky, temps, and winds to match
current trends but overall the forecast remains unchanged.
Pleasant today and then rain arriving tonight.
High pres will slide across the region today. In the meantime,
there is a weak cold moving into NW Maine attm that will slide se
this morning and hit the coast by around noon time. 00Z ua did
show some moisture residing at the 850-700mb layer associated
w/the front. Some of this cloudiness will drift across northern
areas this morning but will be nothing more than scattered in
nature. There is some cooler air behind the front that will sweep
into northern and western areas w/nw winds. Further s across
central and downeast areas, the cooler air will be held off til
later in the day. This will allow for downsloping due to a wnw
wind to push temps into the mid and upper 70s. Northern and
western Maine will see daytime temps in the mid to upper 60s and
much cooler than Wednesday.
Increasing clouds later this afternoon in advance of the low pres
system that has been advertised to move into the region tonight.
Temps will fall back for a while in the early evening but should
level off and actually rise a bit by early Friday morning. Far nw
areas such as Estcourt Station could drop to the upper 30s before
leveling off. The rest of CWA from Northern Maine to the Downeast
will be in the 40s and low 50s.
Now we will move the expected rain. As stated well by the daycrew
on Wednesday, a northern shift in the rain shield has been seen in
the model guidance including the 00z run of the ECMWF. For
continuity, decided stay w/the daycrew`s thinking of bringing pops
to 90-100% and go w/rain. Heaviest rainfall will be across the
northern 1/2 of the CWA arriving by around 11 PM. There could be a
period of heavy rainfall especially from 09-12Z early Friday
morning. The NAM12 showed decent llvl convergence in conjunction
w/a decent jet max of 40-45 kts. Rainfall amounts by 12z(8am)Friday
will be on the order of 0.50-0.75 inches across the northern and
western areas. Rainfall amounts will drop off as one travels s of
a Houlton to Greenville line.
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
Friday will start off on the rainy side across much of the
forecast area as a weak area of low pressure tracks east across
central and downeast Maine Friday morning. The rain will taper to
showers from northwest to southeast by Friday afternoon as the
low tracks east into New Brunswick. High temperatures on Friday
will range from the mid to upper 50s across the north and low to
mid 60s across central and downeast.
Much drier and cooler air will arrive Friday night in the wake of the
low as a large area of high pressure builds toward the region from
central Canada. Expect mainly clear to partly cloudy skies across
the north and mainly clear skies downeast. Lows Friday night are
expected to fall into the low to mid 30s across northern areas.
There will likely to be some stratocumulus clouds around the area
with the upper trof across the region and a bit of a gradient
could keep winds from completely decoupling. These factors may
mitigate widespread frost development. Across downeast areas, lows
will range from the low to mid 40s.
The weekend will definitely feel fall like as a large ridge of
high pressure continues to build southeast out of central Canada
on Saturday. Expect partly to mainly sunny skies across the
region. Highs on Saturday will only range from the low to mid 50s
north and upper 50s to around 60 downeast.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Generally fair weather conditions will prevail through the long
term portion. High pressure will build across the region Sunday
and Monday with dry weather and temperatures a bit below normal
for this time of year. The high will move east later Tuesday
through Wednesday with temperatures moderating to near normal by
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
NEAR TERM: VFR into the evening for all terminals. A drop to MVFR
expected by 03-06z across the northern terminals as rain moves
into the region. Conditions are expected to drop to IFR by 09Z.
VFR for KBGR and KBHB.
SHORT TERM: Widespread IFR/MVFR conditions are expected Friday in
rain with conditions improving to VFR later friday afternoon.
Generally VFR conditions are then expected Friday night through
NEAR TERM: No headlines are expected. Winds will remain light 10
kt or less today. There is a swell component out on the waters
attm per the latest obs w/a period of 10-11 seconds. Seas were
around 2 ft and expected to stay that way through today. A shift
in the wind direction to the s is expected tonight w/an increase
to 10-15 kt as low pres passes by the n. Seas will build a bit to
around 3 ft.
SHORT TERM: Winds/seas should generally remain below small craft
advisory levels through the period. Visibility will be reduced on
Friday to 1 to 3 nm in rain at times.