Area Forecast Discussion
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FXUS61 KCAR 230529
Area Forecast Discussion
National Weather Service Caribou ME
129 AM EDT Sun Apr 23 2017
A trough of low pressure will cross the area this evening. High
pressure builds from the southwest late tonight into Sunday. A
weak cold front will move through the region Sunday night. High
pressure returns Monday into Tuesday.
.NEAR TERM /THROUGH TODAY/...
130 am update...
No chgs needed at this time. Temps are holding nearly steady and
low clds along with areas of fog are enveloping CWA as winds go
calm. Showers hv mvd into New Brunswick as expected.
Orgnl Disc: Low pressure is moving south of the Gulf of Maine
and well south of Nova Scotia. As it moves eastward, an inverted
trough extends to the northwest towards a decaying low in
Quebec. As this inverted trough and associated upper level
trough cross this afternoon and evening, it will cause continued
light rain, drizzle and snow. The snow will be mostly in higher
terrain and is not expected to accumulate...especially since
most of the precip will have fallen by nightfall. With lower
levels saturated, drizzle continuing, and light winds, fog will
tend to thicken and become more widespread later in the evening.
Temperatures will only fall a degree or two overnight from this
afternoon`s readings. The fog and low level moisture will
slowly erode during the course of Sunday. A southwest wind will
commence later in the morning towards midday and accelerate
clearing. With a warming air mass ahead of the cold front,
temperatures will quickly shoot into the 50s and a few 60F
readings are possible towards southern Penobscot County on
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
A cold front pushing into the CWA Sun night will bring some rain
showers to the Crown of Maine, but precip is expected to fizzle
before it moves south of the Katahdin region. The surface
boundary will push south to Bangor by sunrise, and to the coast
by around 8am, if not a bit earlier. However, that`s about as
far as the front gets before it stalls near the coast during the
day Mon, then weakens and dissipates Mon night.
The next system will approach from the Southeastern US, with
precip spreading into the CWA from south to north Tues afternoon
and evening. Given that this system is associated with a 500mb
cut-off low, it`s not surprising that there are some timing
differences between the models. The CMC was the fastest, while
the ECMWF was on the slower side. The GFS was in the middle, but
somewhat skewed toward the ECMWF solution. The forecast for
northward advance of the POPs was weighted more toward those two
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The Low will continue to advance northeast Tue night through
Wed, and is likely to cross Cape Cod Wed eve or night, then move
across the CWA Wed night or early Thu AM. The heaviest, most
widespread rain appears likely between 00z Wed and 00z Thu. As
the sfc low approaches Maine, the upper-level feature will begin
to weaken and get absorbed into the broader flow, and upper-
level ridging following right on the heels of the sfc low may
lead to a fairly quick end to precip as the sfc low passes.
S`ly winds on Thu may push temps above normal, though mostly
cloudy skies appear likely to persist as the next system
approaches from the west. This system, a weakening front, may
bring some rain to the area, but there are disagreements on
timing. The GFS would bring rain in Thu eve and night, but the
ECMWF and CMC both hold off toward sunrise Fri. Regardless, POPs
were kept under 50 pct at this point, and as the front weakens,
precip may dissipate during the day Fri. There are hints of
another system impacting us Fri night into Sat, but as of now
there is significant model discrepancy regarding the timing and
form of both the upper-level flow and sfc features.
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: IFR/LIFR expected all terminals until 12z this
morning. After this time winds will slowly increase and allow
cigs to lift and fog to begin to dissipate. MVFR expected after
mid-morning for northern terminals and after 12z at BGR and BHB.
Expect southern sites will be VFR after 19z while northern
terminals will hang onto MVFR a little longer. FVE may
experience MVFR last several hours of TAF valid time as showers
move in from the north along cold front.
SHORT TERM: Some MVFR to psbl IFR CIGs are likely with the front
for KPQI to KFVE between 00z and 09z Mon. Areas of IFR vsby and
CIGs are likely to develop with fog for KBHB and KBGR between
06z and 12z Mon, and could linger a little longer for KBHB
depending on the timing of frontal passage. Otherwise, a return
to VFR conditions expected Mon afternoon and night. Mid-level
clouds spread south to north during the day Tue, with MVFR
conditions developing Tue eve as rain spreads north. MVFR to
IFR conditions are expected Wed into Wed evening with areas of
heavy rain. Expect clearing late Wed night into Thu.
NEAR TERM: Rain, drizzle and reduced visibility can be expected
through this evening. Seas will slowly decrease from 4 to 5 feet
towards around 2 feet by later Sunday. Winds will also tend to
decrease through the period as high pressure builds.
SHORT TERM: Gusty SW winds expected Sun night and may approach
SCA criteria, then drop off sharply Mon AM. Some areas of dense
fog are also possible overnight into the morning hours.
Moderate E-NE`ly breezes with freshening gusts are on order Mon
night and Tue, approaching SCA levels. Seas will build toward
SCA levels later Tuesday, as well.