Area Forecast Discussion
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FXUS61 KCAR 212349
Area Forecast Discussion
National Weather Service Caribou ME
749 PM EDT Fri Oct 21 2016
Low pressure will develop near Cape Cod late this evening and move
into southern Maine Saturday morning. The low will lift to the
north into Quebec later Saturday night and usher in a much cooler
air mass Sunday through next week.
.NEAR TERM /THROUGH SATURDAY/...
750 pm update...
Area of showers and embedded thunder mvg thru srn New England
this evng in theta-e axis. Expect current training tstms to rmn
just to our west this evng. Showers hv bcm more widespread acrs
CWA in the past hr as higher pw air is getting drawn in fm
subtropical system btwn mainland US and Bermuda. Hv lowered pops
initially for the first svrl hrs but expect rain to bcm more
widespread acrs the area later this evng per hires models. Best
slug of rain looks to affect the area btwn 06z and 15z as 35-40kt
LLJ impinges on theta-e axis as it lifts north thru area.
Given rich pwat air yet to mv in expect rain to get steadily
heavier ovrngt and hv bumped qpf amnts up for the ovrngt with
widespread 1.5-2 inch amnts expected thru the day Sat, with the
bulk of it falling tonight. Any tstms that can dvlp in
increasingly unstable airmass wl be very efficient rain producers.
No other chgs needed to fcst other than to lwr pops initially with
this update and boost qpf amnts.
Prev discussion blo...
The warm front continues to make very slow progress northward this
afternoon with mild maritime air causing widespread light rain and
drizzle. Fog will continue to be an issue this afternoon into
early Saturday morning with this saturated air under a slowly
lowering frontal inversion. Meanwhile, low pressure that was in
Pennsylvania this morning is currently redeveloping off coastal
New Jersey as an upper trough in the western Great Lakes region
continues to dig...take on a negative tilt...and eventually cut
off in New York by Saturday morning. The surface low off the New
Jersey coast will quickly deepen in response to these upper level
dynamics and draw in rich tropical moisture from the remnants of a
storm moving north from the vicinity of Bermuda. This moisture
with associated high PWs and deep warm layer will produce some
heavy rain tonight that will propagate northward towards northern
Aroostook by daybreak Saturday. Embedded thunderstorms are
possible towards the coast later this evening and have specified
isolated Tstorms later tonight into early Saturday morning. All in
all, most areas stand a good chance of receiving over an inch of
needed rain...and some areas could see 1.5 to 2 inches where
heavier showers/thundershowers occur.
Most of heavy rain will end early Saturday morning, but rain will
remain in the forecast through Saturday as the low pressure moves
over western Maine and into Quebec by later Saturday. Light rain
and drizzle will alternate with heavier showers through the day.
The warmer air mass will remain in place one more day with highs
reaching the lower 60s.
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
Rain transitioning to showers and turning colder by Sunday evening.
Low pres is forecast to lift through western Maine by Saturday
evening w/another round of rain lifting across the region. As has
been advertised previously, PWATS well above 1.5 inches and a
deep southerly flow will transport tropical moisture northward.
There could be periods of heavy rain Saturday night w/the slug of
moisture. South winds will shift to the sw and increase to 20-30
mph with some higher gusts across the eastern sections of the CWA
Saturday night into Sunday morning. Low pres will then lift into
Quebec on Sunday w/colder air moving in as winds turn to the west.
The ECMWF is further e w/the position of the low which would lead
to a slower timing of the caa, while the GFS and the NAM are
further w. Decided on a blend positioning the low through central
maine and then into Quebec. Steady rain will transition to showers
by Sunday afternoon. Additional rainfall of up to 0.25 inches are
possible. It will be windy on Sunday w/temps falling off by late
Much colder Sunday night into Monday w/continued caa. Wraparound
moisture w/an upper level disturbance will lead to showers. Snow
showers are possible back across w and nw areas due to cold air
draining down through the column. No accumulation is expected.
Monday to remain unsettled and cold w/rain showers and possible
snow showers. Daytime temps generally in the 40s w/higher terrain
in the 30s.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
Remaining cold and unsettled into Wednesday.
Stacked low pres to residing over the Gulf of the St. Lawrence to
migrate across the region Tuesday into Wednesday. This will mean
on and off showers and even snow showers. Any snow accumulation
will be light and mainly across the higher elevations.
High pres to build in across the area Thursday into Friday but
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR and LIFR restrictions expected to continue this
evening and into the morning hours. Expect heavy rain to move into
BHB after 05z and remainder of terminals after 09z. LLWS looks
less likely and have not included in forecasts.
SHORT TERM: IFR into Saturday night w/periods of rain and gusty
winds. Conditions improving to MVFR for KBGR and KBHB on Sunday
while the northern terminals stay in IFR. Improvement for KBGR and
KBHB to VFR by Sunday w/MVFR for the north. VFR continuing for
KBGR and KBHB for Sunday night into Monday while northern sites
stay at MVFR.
NEAR TERM: Have extended the SCA through Saturday. Winds will pick
up tonight in advance of low pressure moving north into the Gulf
of Maine. Expect steady state winds to reach 25 to 30 knots for
several hours this evening. Winds will then decrease after
midnight, but seas will continue increasing to as much as 9 to 10
feet by daybreak. Seas will remain above SCA criteria all of
SHORT TERM: Looks like Gale Force winds possible for Saturday
night into Sunday. Decided on a Gale Watch Saturday night through
Sunday for 25-35 kts mainly out over the outer zones. This was
collaborated w/GYX. Seas will run 11-13 ft into Saturday evening
and then start to fall back on Sunday as the winds turn to a wsw
direction. Attm, not expecting any major issues for overwash along
the coast. Some minor splashover is possible at the time of high
tide Saturday afternoon into early evening. Winds and seas will
drop off Sunday night into Monday w/the direction becoming more
westerly and seas falling back to 5-6 ft.
Not expecting any flooding issues w/the rainfall. Some nuisance
concerns especially w/culverts plugged from leaves and ponding of
water. Area streams and rivers will show some rises but rainfall
is needed due to very low stream levels.
MARINE...Small Craft Advisory until 8 PM EDT Saturday for ANZ050>052.
Gale Watch from Saturday evening through Sunday evening for