252
FXUS61 KCAR 071317
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
917 AM EDT Tue May 7 2024

.SYNOPSIS...
High pressure will build in from the west today and crest over the
area tonight. Weak low pressure will approach on Wednesday and
slide south of the area Wednesday night. High pressure will
build north of the area Thursday. A new low will develop off the
Mid-Atlantic coast on Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
9:17 AM Update: No major changes with this update. Satellite
data and webcams indicate stratocumulus clouds moving into the
Crown of Maine. Made minor tweaks to account for latest trends.

Prev Disc: A sfc ridge of high pres xtndg from Cntrl Can will
drier conditions to all of the FA tdy, with llvl cool advcn on
breezy NW winds and advcg SC cld cvr from Ern QB resulting in
cooler high temps across the N. S of the SC cld field, high
temps this Aftn will be as warm ovr E Cntrl and even a little
warmer ovr Downeast areas than ystdy due to a downslope,
offshore wind direction resulting in greater llvl mixing and
llvl htg of the airmass. SC cld cvr across the N will be
accentuated by a s/wv trof movg SSE from Wrn Labrador just N of
Nrn ME this Aftn, bring colder air alf for this ptn of the Rgn.
At this tm, any shwrs with this system should remain well N of
the St John vly, but something for the day shift to monitor.

By late in the day, the s/wv will be movg well E of the FA
across the Ern Can Maritimes, taking with the SC cld cvr from
Nrn areas. Otherwise, under clear  skies and dmnshg winds Tngt,
temps will fall to lows near frzg ovr Nrn Vlys by daybreak Wed
with mid 30s to arnd 40 deg swrd toward the coast. High CI/CS
will be advcg ovr Wrn ptns of the FA by daybreak, ahead of the
next weak low pres system.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
Weak surface high pressure will be ridging across the area Wednesday
morning. Meanwhile, a fast moving but shallow shortwave will be
approaching from the west southwest and supporting low pressure
tracking through New York state. This low will bring increasing
clouds Wednesday as it approaches followed by rain moving into
southern areas Wednesday afternoon. Currently there is high
confidence in a light to moderate rainfall over central and southern
areas with this small system, but less confidence in how far north
the rain will come. The latest models are bringing the low far
enough north for at least some light rain over the north Wednesday
night with the rain tapering off to showers throughout the area late
at night.

Low pressure will slide east and away into the Maritimes on Thursday
as weak surface high pressure builds over the north. This will bring
clouds giving way to partial sunshine over the north. There is no
strong mechanism for clearing the sky further south where a corridor
of moisture will linger and the sky will remain mostly cloudy with a
few breaks of sunshine.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Thursday night will remain partly cloudy over the north under weak
high pressure and mostly cloudy across the south. A very weak and
shallow trailing shortwave will carry a small low off the Mid-
Atlantic coast and well south of the area.

Our focus on Friday will be on a new shortwave approaching the Mid-
Atlantic coast and developing a new area of low pressure. Forecast
models continue to struggle with the details of this low with some
models carrying the low north to bring more rain over the weekend
while other models are less able to consolidate a shortwave and
carry a weaker low to our south and east. Will continue to carry
high chance and low likely pops Friday into Saturday as this low
tracks off the shore. The track of this low partly hinges on how
strong and deep a backing shortwave trough will dive into the
Plains. A stronger deeper trough will better pivot the offshore low
north while a weak trough will result in a shallower less amplified
wave ahead of it and thereby allow the low to slip out to sea.

The Plains trough will slide east and combine with the eastern
trough to bring an upper trough lingering over the area on Sunday
producing a mostly cloudy sky with some lingering showers possible.
The trough may begin to move away to the east on Monday. However,
there is currently no strong ridging or surface high to follow, so
unsettled conditions may persist with a partly to mostly cloudy sky
and a chance for spotty showers into early next week.

&&

.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: Tdy...Nrn TAF sites low VFR clgs late Morn into Aftn
with MVFR clgs possible KFVE, otherwise unlmtd VFR. Downeast
sites msly unlmtd VFR. Lgt to mdt NW winds.

Tngt...all TAF sites unlmtd VFR with lgt winds.

SHORT TERM: Wednesday...VFR dropping to MVFR then IFR south,
and possibly dropping to MVFR north late. Light and variable
wind.

Wednesday night...MVFR to IFR. Light E wind.

Thursday...IFR to MVFR becoming VFR late. Light NE wind.

Thursday night...VFR. Light NE wind.

Friday...VFR, lowering to MVFR south late. Light E wind.

Friday night...MVFR north. MVFR to IFR south. Light E wind.

Saturday...Possibly IFR early. Otherwise, MVFR. N wind.

&&

.MARINE...
NEAR TERM: No hdlns anticipated at this tm ovr this ptn of the
fcst. Kept close to blended wv model guidance for fcst wv hts
with wvs msly composed of two spectral groups; a shorter 4 to 6
sec and a longer 10 to 12 sec pd swell.

SHORT TERM: Wind and seas may reach SCA on Friday depending on
the track and strength of low pressure tracking to our south.
There still remains considerable uncertainly on how well this
low will develop. Otherwise, wind and seas will should below SCA
through the week.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.

&&

$$


Near Term...Clark/VJN
Short Term...Bloomer
Long Term...Bloomer
Aviation...Clark/VJN/Bloomer
Marine...Clark/VJN/Bloomer