-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCAR 191012
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
612 AM EDT Fri Apr 19 2024

.SYNOPSIS...
High pressure crosses the region today. An occluded front
approaches Friday night, crosses the region Saturday, then exits
across the Maritimes Sunday. A cold front crosses the region
Sunday night into Monday. High pressure then builds across the
region later Monday into Tuesday. Low pressure approaches from
the west Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
610am update...Raised highs today towards northern and eastern
portions of the forecast area. Changed mention of showers to
rain for late tonight into Saturday. Latest guidance continues
to advertise a soggy Saturday from the I-95 corridor southward.

Previous discussion...
Ridging at the surface and aloft dominates this morning with
little cloud cover. Expect temperatures to warm into the upper
50s to lower 60s with a deep mixed layer. This will tend to
lower dew points towards the upper 20s in the very dry air mass.
An emerging onshore will yield lower high temps on the coast.
Lower 50s are expected before the sea breeze produces lower
afternoon temps. The upper ridge moves east of the area this
afternoon and upper level moisture/cloud cover will increase
ahead of the weakening occluded front.

As the front enters the area tonight, little precip is expected
as the initial shortwave energy will be well north of the
forecast area. However, a second shortwave rotating around the
base of the large scale upper trough in the Great Lakes region
will reinvigorate the front. Recent guidance has gained much
more consensus on the rapid development in a fairly narrow axis
from southern Penobscot County towards southern Aroostook
County. In this corridor, mid-lvl thermal packing quickly
increases late tonight with enhancements to lift and QPF. Still
not expecting more than a tenth or two of one inch of rainfall
by early Saturday morning.

Cloud cover and warm advection will limit lows tonight to the
lower 40s.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A weak cold front crosses the region on Saturday. QPF models
have increased rainfall amounts since the last model run with
accumulations nearing 0.5 inches across Downeast Saturday
morning. SW flow is expected to increase, especially in the
north due to the tightening pressure gradients near the
occlusion. Expect temps in the low 50s. By Saturday night, the
front will exit over the waters with a weak trof behind the
front assisting in some convective development in the south. All
rain showers should end after midnight with upper level ridging
moving in. Clouds should begin to clear later in the night,
dropping temps towards freezing.

By Sunday, another cold front approaches with shortwave energy
ahead of the front. Though weak, showers are expected across the
north, with possible snow showers in the North Woods in the
morning. Temps should be above normal in the 50s. By Sunday
night, the cold front will push through the region by late
night. The 925mb model temps show cold air advecting into the
region after midnight, thus a steady decrease through the night.
Due to the decreasing temps, any showers in the north should
switch to snow.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As the cold front exits over the waters on Monday, high pressure
should move in. Cold air from the front should keep temps below
normal. Though cloud cover should decrease to make for sunny
skies during the day, breezy W winds will mix the cold air down
keeping the north in the mid 30s and south in the mid 40s. The
next system is expected to move into the area by Wednesday.
Models are still inconsistent with the track and timing of the
system. The Canadian has the system much further north, while
GFS and Euro have the center of the system moving over the
state. Nevertheless, the models due agree on a tight temp
gradient moving through the region by Wednesday night through
Thursday, which will switch rain over to snow through the
Central Highlands and north. Snow is possible further south as
surface temps could fall to freezing. By next weekend, high
pressure should return.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: VFR weather is expected until late tonight when MVFR
cigs in rain are expected. Tempo IFR cigs are possible by early
Saturday morning. LLWS is expected after midnight with
southwesterly winds up to 45 kt at FL020.

SHORT TERM: Saturday...MVFR possible in showers. LLWS possible.
S winds 5-15 kts.

Saturday night...VFR. W winds around 5 kts.

Sunday...VFR south, MVFR north in rain showers. WSW winds 5-15
kts.

Sunday night-Monday...VFR, except chance MVFR SHSN Sunday night
north. NW wind gusts may approach 30 to 35 kt on Monday.

Monday night-Tuesday...VFR.

&&

.MARINE...
NEAR TERM: No significant weather is expected in terms of fog,
winds or seas. Southerly wind gusts will increase to 20 kt
tonight, but stability should prevent any gusts reaching
advisory criteria. In response to the winds, seas will build
towards 3 ft later tonight.


SHORT TERM: Winds and seas should remain below SCA levels until
briefly on Sunday night, with increased winds. Winds should
decrease again Monday morning, then increase Monday afternoon.
Winds return to SCA Tuesday afternoon, then decrease for the
night.

&&

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

&&

$$


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