363
FXUS61 KCAR 010035
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
835 PM EDT Tue Apr 30 2024

.SYNOPSIS...
Low pressure crosses the northern Mid-Atlantic states tonight,
then passes south of the Gulf of Maine on Wednesday. High
pressure builds to the north Wednesday night, followed by weak
low pressure passing to the southwest Thursday. High pressure
then builds down from the north Thursday night through Friday
night, then slowly retreats to the north and east through
Saturday night. A frontal system approaches from the west on
Sunday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
834 PM Update: Based on latest radar ref returns across
Cntrl/SW ptns of the FA, we optd to bump PoPs upwards a little
ovr these areas Ovrngt xtndg ESE to Downeast areas. Although dry
sub-cld air is resulting in some initial evaporation of rn, sig
area cvrg of 30+ dbz refs would support some shwrs reaching the
ground ovr these areas, with additional returns likely to advc
ESE from Wrn ME into the lower Penobscot vly and coastal
Downeast areas by late Tngt. Further N, virga is more likely
given lighter ref returns. Fcst 6hrly QPFs for the 00-06z and
06-12z pds were adjusted accordingly, with modest total rnfl
amts of less than a tenth even where max PoPs reach the likely
range ovr the far SW ptn of the FA.

Otherwise fcst hrly temps/dwpts were updated into the Late Ngt
hrs from latest avbl erly eve sfc obs with little no chgs to
fcst Ovrngt low temps.

Prev Disc: A ridge of high pressure gradually shifts eastwards
into the Canadian Maritimes this evening, as low pressure
approaches from the southwest. Due to substantial mid level dry
air, showers will be slow to move in this evening, but once this
dry layer finally saturates, isolated to scattered rain showers
will be able to reach the ground through the night tonight
across the Downeast region. Light showers will result in little
measurable precip overnight. Temperatures will only fall into
the upper 30s to lower 40s over most of the area due to
increased cloud cover. The surface low will continue to track
south of the Gulf of Maine and exit to the southeast Wednesday
morning, leading to showers clearing out of the area. Mostly
cloudy skies will continue to linger through the day on
Wednesday, but any breaks in the clouds will allow temperatures
to rise into the mid to upper 50s through the region.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
Northern stream ridging transits the area Wednesday night, with
associated subsidence keeping things dry. However, will see
partly to mostly cloudy sky conditions with low to mid level
moisture increasing overnight on the backside of the ridge. Lows
Wednesday night should be near normal, ranging from the mid 30s
to around 40.

A northern stream trough crosses New England Thursday, bringing
some isolated to scattered showers with it. There is some
question as to how far NE any precipitation will be with this
system. Some models even suggest that SW zones could just get
clipped by this system with little or no precipitation
elsewhere. For now, have limited pops to high end chance over
central and Downeast zones. Highs on Thursday should be near to
slightly below normal. Ranging from around 50 to the upper 50s.
Coolest temperatures should be near the immediate coast with
onshore flow.

Deep layered ridging builds in Thursday night and Friday, so it
should be dry. However, with moisture progged to be trapped
under the developing subsidence inversion and shortwaves
embedded in the flow, should see partly to mostly cloudy sky
conditions. Lows Thursday night should be near to slightly above
normal and highs on Friday a few degrees below normal.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Deep layered ridging continues to build in Friday night through
Saturday, then pass to the east Saturday night. Associated
subsidence should keep things dry.

Depending on exactly how fast the deep layered ridge continues
to exit to the east on Sunday, will determine, how much, if any
showers occur over the region. For now expect mainly isolated
showers, with showers possibly more scattered in nature over far
NW zones late in the day.

SW flow aloft Sunday night, with a passing shortwave should
bring some scattered showers. A northern stream trough then
passes on Monday, followed by a northern stream shortwave Monday
night, so should see some isolated to scattered showers during
this time frame.

The region should be under NW flow aloft, with some shortwaves
possibly embedded in the flow. So have a slight chance of
showers in the forecast. It is very hard to pin down shortwaves
in a fast flow aloft this far out.

Temperatures should be near normal Friday night and Saturday,
then above normal Saturday night through Tuesday.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
NEAR TERM: VFR conditions continue across all terminals through
the early evening. Cigs will begin to lower over Downeast
terminals late this evening, falling to MVFR overnight tonight
as scattered rain showers move through. Northern terminals are
expected to remain VFR, but PQI and HUL may briefly dip towards
MVFR around 10 to 12z before improving once more. Downeast
terminals will be slower to return to VFR Wednesday, and may
remain MVFR until late in the afternoon. Winds generally light
and variable, with a few lingering northerly gusts at northern
terminals late this afternoon.

SHORT TERM:
Wednesday night...VFR.

Thursday...VFR northern terminals, with MVFR possible at
southern terminals.

Thursday night-Saturday night...VFR.

Sunday: Most likely VFR, with a low chance of MVFR in the
afternoon. S-SW winds G15-20KT possible.

&&

.MARINE...
NEAR TERM: Winds and seas will remain below small craft levels
tonight through Wednesday, with winds becoming NE with gusts to
15 kts and seas 1 to 2 ft. Scattered light rain showers possible
overnight tonight.

SHORT TERM: A light to at times moderate pressure gradient over
the waters Wednesday night through Sunday, should limit
sustained winds to at most 10 to 15 kt. With no significant
swell forecast, seas should be around 2 ft or less late this
week through the weekend as well.

&&

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

&&

$$


Near Term...VJN
Short Term...Maloit
Long Term...Maloit
Aviation...VJN/Maloit
Marine...VJN/Maloit