900
FXUS61 KCAR 310838
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
438 AM EDT Fri May 31 2024

.SYNOPSIS...
High pressure slowly builds in this weekend, with low pressure
approaching from the east on Sunday. Weak high pressure returns
through Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
A cool start to the morning with some patchy to areas of frost
across the North and some river valley fog. Today, the 500mb low
pressure begins to drift NE of the Gaspe Peninsula with the
trof axis extending south to the Maine/New Brunswick border and
drifts east into the Maritimes by later in the day. 1026mb
surface high pressure drifts slowly east over Lake Erie today
which is still too far away to full take over control of our
weather. Hi-Res models have been consistent since yesterday
diving a piece of 500mb vorticity on the backside of the trof
into Maine this afternoon. The day starts out mostly sunny but
turns partly sunny and hi-res CAMs consistent on producing some
convection this afternoon. Modeled soundings continue to show
steep low-level lapse rates around 9C/km with mid levels
approaching 7C/km. Although its a well mixed below 850mb there
is some SBCAPE up to 200-400j/kg expected. Given the lower
freezing levels and convective temperatures around 67-69F we can
expect a few isolated to scattered showers. Given the
thermodynamics described above cannot rule out a few isolated
lightning strikes so opted to add isolated thunder to the grids.
The best chance for any showers and thunder will be tight to
where the vorticity transects the state today which will be from
the Moosehead Region south to Bangor then perhaps Bar Harbor.
Everywhere else will remain dry with just some cu. High
temperatures today will be in the mid to upper 60s across the
north and with the light north wind it will be a downslope off
the Longfellow Mtns so expect upper 60s to low 70s in the
Highlands to the Downeast coast. Given the temperatures on the
coast and the very cold Gulf of Maine waters have hoisted a
Beach Hazard Statement at the request of the United States Coast
Guard.

Tonight, showers end very quickly this evening with the loss of
daytime heating and drier air works into the area. Partly cloudy
skies become clear but a warmer airmass associated with the
approaching 500mb ridge works into the area. This means although
there will be a steep low-level inversion around 500-1000ft the
surface temperatures wont be as cold despite decoupling. Expect
upper 30s to low 40s across the north with mid 40s for the
Central Highlands to the Downeast coast. Decent weather
conditions expected for skywatchers on the potential for more
Northern Lights activity given the G2 Geomagnetic Storm Watch
issued by the NWS Space Weather Prediction Center.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
The upper level longwave trough will begin to shift eastward
through the day on Saturday. As this occurs, a north-south
oriented jet streak will pull southwards through the state, with
the front right entrance region crossing over the forecast area.
This synoptic setup will setup will support instability across
the forecast area. What is lacking for the day on Saturday is
any significant source of moisture for shower or storm
development. Given this environment, an afternoon cumulus field
is likely, especially across the eastern half of the forecast
area.

A ridge will begin to build into the area Saturday night into
Sunday, which will provide subsidence to keep skies mostly clear
and precip chances to a minimum. However, recent CAM guidance,
such as in the NAM and RGEM, have begun to suggest that the
ridge will build in a little more slowly than global models have
been projecting. As the previous upper level trough begins to
shift towards a neutral tilt, this slower solution maintains
some weight. The consequence to a slower ridge build is that
would allow for a surface low to retrograde far enough westward
into New Brunswick to bring rain showers across the eastern
Maine border. Moisture support would then come from the Canadian
Maritimes, and synoptic instability provided by the upper level
trough. Winds will be relatively light through this time, but
upper level NE flow could lead to downsloping which will
continue subsidence over NE Aroostook, downstream of higher
terrain in New Brunswick, and keep the best chances for rain
showers across Washington County. Even still, any rain that does
develop will be light.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
A ridge of high pressure will continue to slowly move into the
area through the first half of the upcoming week, with mostly
clear skies and little to no rain chances. Heading into the
middle of the work week, moisture will begin to slowly return to
the area, with enough moisture returning for diurnal cumulus
to continue to build into showers and storms. This said, the
synoptic pattern is likely to still be that of which is under at
least some influence of a ridge, though shortwaves may approach
from the west during this time.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR through tonight. FEW-SCT cigs today becoming SKC
tonight. N-NW winds today 5-10kt becoming light and variable
tonight.

SHORT TERM:
Saturday - Tuesday: Generally VFR conditions across all
terminals, with winds light and variable each night. Saturday, N
winds 5 to 10 kts, otherwise each day light N to NE winds around
5 kts. Slight chance (20%) of MVFR cigs on Monday with -SHRA and
increased cloud cover for Washington County terminals up through
eastern Aroostook KHUL through KCAR.

&&

.MARINE...
NEAR TERM: Winds/seas below SCA conditions through tonight. W-NW
today less than 15kt becoming N around 5kt tonight. Seas 2-3ft
today with a period of 7sec becoming 1-2ft tonight. Sea surface
temperatures in the mid to upper 40s extend from the Downeast
coast out 25nm and east to the Hague Line including
Passamaquoddy Bay.

SHORT TERM: Winds and seas will continue to remain below small
craft advisory conditions through the weekend and into early
next week. Winds will be light with gusts around 10 to 12 kts
and generally offshore in direction, while seas sit around 1 to
2 ft. There is a chance for patchy fog over the waters Sunday
night, reducing visibilities.


&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Frost Advisory until 7 AM EDT this morning for MEZ002-010.
     Beach Hazards Statement from 8 AM EDT this morning through
     this evening for MEZ029-030.
MARINE...None.

&&

$$


Near Term...Sinko
Short Term...AStrauser
Long Term...AStrauser
Aviation...Sinko/AStrauser
Marine...Sinko/AStrauser