998
FXUS61 KCAR 260151
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
951 PM EDT Tue Jun 25 2024

.SYNOPSIS...
A warm front will lift across the region tonight. A cold front
will approach later Wednesday, then cross the area Wednesday
night and Thursday morning. High pressure then builds in from
the west through Friday, then slowly slides offshore Friday
night and Saturday. A cold front approaches Saturday night, then
crosses the area on Sunday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Update...
Clouds will continue to increase overnight with the approach of
a weak warm front. Cant rule out isolated to scattered showers
after midnight with this feature. Expect overnight lows in the
lower 60s. Just minor tweaks to hourly temps and dew points,
otherwise no other changes.

previous discussion
Surface/upper level ridging exits across the Maritimes tonight
while a warm front lifts across the region overnight. Diurnal
clouds will dissipate this evening leaving mostly clear skies
across the forecast area early tonight. Expect increasing clouds
overnight with the warm front. Could also have isolated/scattered
showers across mostly northern and west-central areas late
tonight. A cold front begins to approach later Wednesday.
Expect partly sunny/mostly cloudy skies along with isolated to
scattered showers across mostly northern and central areas early
Wednesday, with scattered showers and possible isolated
thunderstorms during the afternoon. Across Downeast areas,
expect partly sunny skies Wednesday with isolated afternoon
showers also possible. Low temperatures tonight will range from
around 60 to the lower 60s across much of the forecast area,
with upper 50s to around 60 along the Downeast coast. High
temperatures Wednesday will range from the upper 70s to lower
80s north, to the lower to mid 80s interior Downeast. Upper 70s
to around 80 are expected along the Downeast coast.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
A northern stream shortwave moves into the area Wednesday
night, then exits to the east Thursday morning. High resolution
models are suggesting that the bulk of any precipitation with
this system will be focused across Downeast Maine and the
Bangor-Penobscot region, with lesser amount/extent farther N.
Some models even suggest a good bit of the North could stay dry
with this system. As a result, have limited categorical pops to
the Bangor-Penobscot Region and Downeast Maine and tapered pops
to chance across most of the North. Further adjustments likely
to this, as there is quite a bit of spread with this system.

There is still the potential for 1/2-3/4 of an inch of rain with
this system, with locally higher amounts possible in any
stronger convection - which likely will be found across the
Bangor-Penobscot Region and/or Downeast Maine. Confidence in
amounts above 1/2 an inch greatly decrease as you go north of
Millinocket.

Lows Wednesday night should be near normal across the North and
around 5 degrees above Normal across the Bangor-Penobscot Region
and and Downeast. Highs on Thursday should be around 5 degrees
below normal.

Another northern stream shortwave passes Thursday evening, but
with less moisture to work with, have limited pops to slight
chance over far NW zones, with some lingering showers also
possible over far SE Maine. Lows Thursday night should be around
5-10 degrees below normal.

Northern stream shortwave ridging builds in on Friday, so it
should be dry with minimal cloud cover, except for maybe some
afternoon cumulus clouds. Highs on Friday should be a few
degrees below normal.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
The models continue to have disagreement over the timing and
strength of northern stream systems through this time frame. As
a result the entire forecast from Friday night-Tuesday is of
below normal confidence.

Friday night should feature some weak northern stream ridging so
it should be dry.

The ECMWF and GFS, as well as most ensemble model members
suggest a northern stream shortwave approaches Saturday then
crosses to the north Saturday night, followed by the main
northern stream trough building in on Sunday. The CMC and a
smaller number of ensemble members are about 12 hours slower
with this system. But in terms of how fast the system exits, the
ECMWF is slower in doing so than the GFS, so ends up not ending
precipitation until late Sunday night, similar to the CMC.

Noting that until the unpredictability of the short term is
resolved, and how it is resolved, will have quite a bit of
bearing on how this scenario plays out in the long term. As a
result cannot with any confidence rule out any particular
scenario. So just leaned towards the solution favored by most
models at any given time.

For now have chance pops Saturday, increase to likely for
Saturday night and Sunday, then lower to chance Sunday night. If
the faster GFS/ECMWF idea is right, could see a rumble of thunder
Saturday afternoon/evening. Similarly, if slower system exit of
CMC/ECMWF is correct, could also see a rumble of thunder Sunday
as well.

Main mid-upper level trough axis crosses on Monday and other
than possibly some lingering showers early over far SE Downeast
Maine, it should be dry in response to a drying of the low-mid
levels.

Deep layered ridging builds in Monday night and Tuesday so it
should be dry due to subsidence under the ridge.

Temperatures should be below normal Friday night-Saturday, near
normal Saturday night-Sunday night, then below normal Monday and
Monday night, before returning to above normal levels on
Tuesday. Given the low confidence in the overall pattern through
at least the weekend, the confidence in this temperature
forecast is below average.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
NEAR TERM: Generally expect VFR conditions across the region
tonight. However, occasional MVFR conditions possible across
northern areas late with any showers. VFR/MVFR across northern
and central areas with scattered showers Wednesday, with an
isolated afternoon thunderstorm also possible. Generally VFR
Downeast Wednesday with isolated afternoon showers possible.
Variable winds 5 to 10 knots, becoming south tonight.
South/southwest winds 10 to 15 knots with gusts up to around 20
knots, becoming southwest/west Wednesday.

SHORT TERM:
Wednesday night...VFR in the evening, then MVFR or lower
possible at northern terminals and IFR or lower probable at
southern terminals. W-NW winds G15-20KT possible in the evening.

Thursday...MVFR or lower possible at northern terminals with IFR
or lower likely at southern terminals in the morning, then
becoming VFR throughout in the afternoon.

Thursday night through Friday night...VFR. NW winds G15-20KT
possible Thursday evening and Friday morning. LLWS possible
Friday night.

Saturday...VFR, with a chance of MVFR late. LLWS possible.

Saturday night-Sunday...MVFR or lower possible. LLWS possible at
southern terminals. SW-W winds G15-20KT possible Sunday.

&&

.MARINE...
NEAR TERM: Winds/seas generally below small craft advisory
levels tonight through Wednesday. However, seas could begin to
approach small craft advisory levels along the outer edge of
the waters later Wednesday.

SHORT TERM: Sub-SCA conditions are currently forecast on all
waters Wednesday night-Saturday night, however seas on the
coastal ocean waters will be near/just below the SCA threshold
from Wednesday night into Thursday night, mainly due to a
persistent swell.

SCA conditions are possible on the coastal ocean waters Sunday,
with sub-SCA conditions currently forecast on the intra-coastal
waters.

&&

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

&&

$$


Near Term...TWD/Norcross
Short Term...Maloit
Long Term...Maloit
Aviation...TWD/Norcross/Maloit
Marine...TWD/Norcross/Maloit