193
FXUS61 KCAR 071958
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
358 PM EDT Mon Apr 7 2025

.SYNOPSIS...
Low pressure approaches from the west tonight, tracks across
southern Maine Tuesday, then tracks into the Maritimes Tuesday
night. High pressure builds to the south, then east Wednesday
through Thursday night. Low pressure slowly tracks from the Mid
Atlantic states Friday to off the southern New England coast by
Saturday evening.

&&

.NEAR TERM /THROUGH TUESDAY/...
The low pressure system will approach from the SW tonight.
Models are in good agreement with the southern stream flow
remaining over the waters tonight. This will keep the majority
of cloud cover to the south. Some high clouds will fill into the
north tonight. With the clearing skies and calm wind in the
north, radiational cooling will bring temps down into the mid
20s. Clouds in the south will keep temps hovering around
freezing.

For Tuesday, the center of the low pressure system with the
northern trof will progress north of New York and slowly move E.
The main question will be how/if this low will merge with the
southern stream low. As of this update, models have the
northern low merging with the southern stream low by the
afternoon. Models indicate that the surface system will follow
the 700 mb track. With the majority of the frontogenesis under
700 mb, there will be snow banding setting up with the low
center. Unfortunately, confidence is low on where the banding
will set up.

Current split of the models is as follows: half of the models
agree on the center of the low tracking further south pulling
the northern wave across the majority of Somerset county, then
swinging the boundary NE as snow amounts decrease. This would
make the band weaker into the forecast area. The other half of
the models agree on the center of the low tracks across Downeast
then exiting NE by Tuesday night. This would keep the heavier
snow band to the north of the low, bringing higher snow amounts
across the center of the region.

Due to the 50/50 split of the models, decide to go with a middle
ground by increasing QPF across the Somerset county and across
the center of the region. This will increase snow amounts across
the area for the afternoon with localized higher amounts.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
A northern stream shortwave trough exits to to the northeast
Tuesday night. Snow will taper off from SW to NE as it does so.
There is still quite a bit of uncertainty on how quickly this
system exits, and the exact track it takes. As a result, there
is still quite a bit of uncertainty as to exactly how much
snow falls Tuesday night. For now, it appears that any banding
will be focused from N Somerset down into the Central Highlands,
so did reduce snow totals across Aroostook and N Penobscot in
particular. Given the uncertainty, have opted to keep winter
weather headline end times and type as is for now. With winds
increasing on the backside of the system, have introduced
blowing snow Tuesday night, mainly over higher elevations.

Lows Tuesday night should be around 5 degrees below normal.

The region remains at the base of a northern stream trough
Wednesday and Wednesday evening, before its axis lifts to the NE
late Wednesday night. With dry low levels, it should be dry,
however a few flurries across the North cannot be completely
ruled out. However, the confidence in any flurries is not high
enough to reflect in the forecast at this time.

Highs on Wednesday and lows Wednesday night should be around 10
degrees below normal.

Northern stream ridging builds in on Thursday, with associated
subsidence keeping things dry. Highs on Thursday should be near
to slightly below normal.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Deep layered ridging remains over the area Thursday night into
at least Friday. Depending on how fast the ridge axis lifts to
the northeast Friday, will largely determine how fast, if at
all any precipitation builds in late Friday. Also note, that
some models suggest that some shortwaves make it into the heart
of the ridge, so do run slight chance pops Thursday night and
Friday, except for chance pops late Friday over far SW portions
of the CWA.

The models then are all over the place with how the handle a
cutoff low from Friday night-Monday. Given the inherent
uncertainty with cutoff lows, have capped pops at chance and
gone with shower vice stratiform wording.

Temperatures should be near to slightly above normal Thursday
night through Monday. Note given the uncertainty with the cutoff
low, the temperature forecast during this time frame is of
below normal confidence.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
NEAR TERM: VFR at all terminals through 03z. BGR and Downeast
terminals deteriorate to MVFR after 03z, then to IFR after 06z
with -SN. VFR at Aroostook terminals becomes MVFR 08z-11z with
low cigs and possible -SN. Winds W-NW 5-15 kts this afternoon,
becoming light and variable tonight.

SHORT TERM:
Tuesday night...IFR or lower improving to VFR from SW to NE,
with possible exception of NE terminals, where there is a low
chance that MVFR conditions could hold on into late Tuesday
night.

Wednesday-Thursday night...VFR, with possible exception of a
very low chance of MVFR early at NE terminals. WSW winds
G15-20KT possible Wednesday-Wednesday night.

Friday...VFR, with MVFR possible late at southern terminals. S
winds G15-20KT possible.

Friday night-Saturday...MVFR or lower possible. LLWS possible.

&&

.MARINE...
NEAR TERM: Winds and seas will remain below SCA levels tonight
and Tuesday afternoon. Winds and seas will increase Tuesday
afternoon with winds reaching gale force. Thus a Gale Warning
has been issued for the outer waters and a small craft advisory
for inner waters.

SHORT TERM: Gales on the coastal ocean waters Tuesday night, so
converted the gale watch to a gale warning, and continues SCA
on intra-coastal waters then. SCA conditions likely on all
waters Wednesday, possibly continuing into Wednesday night on
the coastal ocean waters. There should then be sub-SCA
conditions on all waters Thursday-Friday, though a few gusts on
Thursday to around 25 kt on the eastern coastal ocean waters
cannot be ruled out, especially in the morning.

SCA conditions are possible on the coastal ocean waters Friday
night and Saturday, but appears it should remain below SCA
levels on the intra-coastal waters during this time frame.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory from 4 AM Tuesday to 4 AM EDT
     Wednesday for MEZ001>006-010-011-031-032.
MARINE...Gale Warning from 4 PM Tuesday to 6 AM EDT Wednesday for
     ANZ050-051.
     Small Craft Advisory from 4 PM Tuesday to 6 AM EDT Wednesday
     for ANZ052.

&&

$$

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