514
FXUS61 KCAR 232309
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
609 PM EST Sat Nov 23 2024

.SYNOPSIS...
Low pressure will track across Nova Scotia this evening, then
exit across the Maritimes Sunday. High pressure builds toward
the region Monday. Low pressure approaches from the west Tuesday
and will lift to the north of the area Wednesday. High pressure
builds Thursday.

&&

.NEAR TERM /THROUGH SUNDAY/...
6:09 PM Update: A 972 Millibar low is over the southeast corner
of New Brunswick this evening. The low is vertically stacked
and will remain quasi-stationary this evening before slowly
beginning to move east after midnight. Moisture continues to
wrap around the low and into much of northern and eastern Maine.
The steadiest of the precipitation is across the eastern half
of the CWA. Reports that the rain has mixed with snow in Blaine
as well as near Washburn early this evening. As the air mass
very slowly cools this evening the rain will begin to mix with
and change to snow for more areas, especially north of
Millinocket. It will also be a windy night with a NNW wind
gusting to 35 mph at times. The ongoing forecast handles things
well with only very minor tweaks based on the current and
expected conditions tonight.

Previous discussion:
Low pressure over Prince Edward Island continues to drift and
rotate precipitation into much of Eastern and Northern Maine.
Latest band of precip is stretching from the St. John Valley
southward through Eastern Aroostook into Washington county.
Across the North Woods and St. John Valley the winds have
shifted to NNW and allowing for some cold air to drain and
beginning to mix rain and snow. Expecting across the north a
general trend towards light snow in the North Woods and
rain/snow mix in locations mainly north of Moosehead Region and
Baxter Region. Elsewhere, expecting scattered rain showers with
temperatures across the area falling back into the 30s with
around 32F north and upper 30s south. Cannot rule out an inch or
so in the North Woods but anywhere else will be at most a
dusting. NW winds remain gusty tonight with the pressure
gradient and decent mixing of the 925mb LLJ. Gusts 25-40mph at
times with the higher gusts up in the terrain of the Longfellow
Mtns. We have seen a few isolated power outages across Hancock,
Penobscot and Piscataquis counties and cannot rule out a few
more tonight with the winds but nothing widespread expected.

Tomorrow, the upper low remains locked over the Maritimes and
unsettled weather remains with pieces of shortwave energy
rotating over Maine. Expecting any rain/snow showers north to
convert back over to rain with the most showers north tomorrow
and fewer showers south. Temperatures will warm into the upper
30s north and low 40s south. The pressure gradient remains tight
with the ridging to our west so NW winds 10-20mph gusting
25-35mph at times.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
For Sunday night, the vertically stacked low in the Gulf of St
Lawrence will be the primary weather maker. A tight pressure
gradient on the backside of the low will ensure gusty northwest
winds over 30 mph for much of Sunday night. A few light snow
showers are expected Sunday night as moisture under H7 continues
to wrap into the area and the boundary layer temperatures drop
below the freezing mark.

The low will fill and drift eastward Sunday night into Monday
with a resulting decrease in winds and shower chances by Monday.
High temps will be mostly in the low to mid 40s.

Upper level and surface ridging builds Monday night. However,
stratocumulus will persist over the north and high clouds will
be arriving from an approaching low. As a result, lows will only
drop to the mid to upper 20s over most of the area...and lower
30s towards Presque Isle where thicker clouds continue all
night.

On Tuesday, the upper level ridge moves through the area early
and precip will break out in the morning ahead of a warm front.
Given the early morning temperatures below freezing, freezing
rain is a possibility in the morning with a warm layer aloft.
This would be most likely west of Bangor, Millinocket and Fort
Kent. Boundary layer temperatures will warm above freezing
further east, limiting the threat of frozen precip.

A triple point low forms near the coast Tuesday afternoon and
will cut off warm advection northward. A fairly sharp upper
level shortwave will ensure decent lift with this feature. The
key questions at this point will be the exact track and strength
of this low. The low will move out of the area quickly enough to
limit QPF to around a half inch or less. As the low develops,
the trend will be for a changeover from rain to snow late in the
day. This will be mostly likely for the North Woods and terrain
over 1000 ft, but will spread eastward to lower elevations
Tuesday evening.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The storm is expected to move out the area Tuesday night with
precip ending as snow in the northern half of the area. All
told, locations in eastern Aroostook County could see an inch or
so while higher terrain locations in the North Woods could
possibility measure amounts as high as 3 inches.

The upper low remains in the area Wednesday with the threat of
snow showers in the north and western mountains. Amounts will
probably be an inch or less. For the rest of the area, the main
story will be gusty west winds up to 20 mph and high
temperatures reaching the upper 30s to lower 40s.

Transitory high pressure builds Wednesday night into Thursday
morning. The air mass is cold enough to support lows in the low
to mid 20s...even with cloud cover. Highs will be a bit cooler
Thursday with readings mostly below 40F.

Attention then turns to the late week storm that certainly has
the potential to be the first significant winter storm of the
season for the area and will be followed by the coldest air mass
of the season to date. The forecast track and resultant P-types
remain very much in question. Using a blend of guidance, we
generated a storm track towards eastern Nova Scotia and a mix of
precipitation. That means mostly rain on the coast and mostly
snow in the North Woods.

Confidence on the storm affecting the area is high enough to
assign likely PoPs by Friday. Most guidance is showing a decent
slug of southern stream moisture, rapid cyclogenesis Thursday
night into Friday and a powerful negatively tilted trough
quickly becoming vertically stacked. However, as stated, our
confidence on the storm track is low given the wide variety of
model solutions ranging from a track west of the state to a
track south of the benchmark.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: North Terms...MVFR cigs becoming MVFR/IFR. -RA
becoming -RA/-SN mix. NW winds 10-20kt with gusts up to 35 kt
possible. Tomorrow becoming MVFR again with NW winds 15-25kt.
VCSH/-SHRA expected.

South Terms...MVFR this evening gradually becoming low end VFR
with -RA becoming VCSH/-SHRA. NW winds 10-20kt with gusts up to
35kt possible. Tomorrow low end VFR. -SHRA/VCSH possible. NW
winds 10-20kt with gusts up to 30kt possible.

SHORT TERM:
Sunday night into Monday night...MVFR cigs north of HUL and GNR.
VFR most likely for BGR and BHB. Northwest winds 15 to 25
kt...decreasing for Monday.

Tuesday into Tuesday night...Trend towards IFR cigs for all
terminals. LLWS possible. South winds becoming light then
northwesterly by later Tuesday night.

Wednesday into Wednesday night...Tempo MVFR cigs north of GNR
and HUL, otherwise VFR. West winds 10 to 15 kt.

Thursday...VFR.  Light winds.

&&

.MARINE...
NEAR TERM: Gale Warning has been extended into the short term.
NW Gales continue through tomorrow with gusts up to 40kt at
times. Seas 3-5 ft over the Intra-Coastal waters tonight with
6-9 ft on the Coastal Waters and continues into tomorrow. Rain
may reduce vsby at times through tomorrow with precip becoming
showers tomorrow.

SHORT TERM: Gale conditions persist Sunday night and have
extended the warning as a result. A Small Craft Advisory will
probably follow the warning for Monday. The next wind event will
start Tuesday night and continue through Wednesday night. At
this point, an advisory would appear to be warranted. A
Noreaster is possible late week.

&&

.EQUIPMENT...
A technician is working on the KCBW radar this evening, and the
radar will be down intermittently this evening.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Gale Warning until 7 AM EST Monday for ANZ050>052.

&&

$$


Near Term...CB/Sinko
Short Term...MCW
Long Term...MCW
Aviation...CB/Sinko/MCW
Marine...CB/Sinko/MCW
Equipment...CB