643
FXUS61 KGYX 091620
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1220 PM EDT Wed Apr 9 2025

.SYNOPSIS...
High pressure brings a return to drier and warmer conditions
for the middle of the week. A cutoff low then stalls south of
New England on Friday through the weekend, bringing an extended
period of cool and unsettled weather conditions. The system
then moves away early next week with a return to drier and
warmer conditions.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1220 PM Update...Have mainly refreshed winds, temperatures and
sky cover to align with the latest observed trends. Breezy NW
winds will gradually subside through the afternoon with mostly
sunny skies.

1005 AM Update... Minor update to T/Tds and sky cover to reflect
the latest trends.

Previously...
Latest RAP13 surface pressure analysis early this Wednesday
morning shows low pressure located over Nova Scotia with broad
cyclonic flow prevailing over New England. Northeast radar
mosaic does show some weak returns extending from the mountains
down through the Capital Region of ME and towards the Mid-Coast.
ASOS observations along with webcam imagery indicates this is
resulting in some visibility restrictions (especially over the
Mid-Coast) but little in the way of additional snow accumulation
is expected. Therefore, cancelled the winter weather advisory a
little early. Locally slippery travel is still likely though
this morning as any residual moisture/slush has since frozen.
Will likely need to issue a special weather statement to
highlight this threat within the next hour or so for the
commute. It will otherwise remain a brisk morning with
windchills into the single digits and teens.

Low pressure will continue to retreat well to the northeast of
the region today as high pressure begins to nudge in from the
southwest. Gusty northwesterly winds will persist through this
afternoon due to the combination of the lingering pressure
gradient force along with deep mixing. Gusts between 25-35 mph
can be expected.

Speaking of mixing, moisture profiles indicate that we will be
tapping into a very dry airmass aloft this afternoon, which will
help to lower RH down into the teens for some areas south of
the mountains. It will otherwise be a partly sunny day as high
Froude Numbers will likely result in some added cloud cover this
afternoon. It will be unseasonably cool with high temperatures
only into the 30s to middle 40s from north to south.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
High pressure will move across the region tonight, resulting in
mainly clear skies as well as light and variable winds. This
combined with the low dew points that will be in place will set
the stage for likely strong radiational cooling. Used MOS
guidance for overnight lows, which brings some valleys down
into the lower teens with 20s elsewhere.

High pressure will begin to move offshore on Thursday ahead of
the the next storm system. This will allow for gradually
increasing clouds from west to east but southerly flow will help
to boost high temperatures into the upper 40s/low 50s away from
the coast.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
1040 PM Update...Little change to the extended forecast. Main
focus continues to be on potential rainy system for the
weekend, possible starting as wintry precipitation for some
locations Friday night.

Overview...

High pressure exits New England on Thursday night, and settles
northeast of the region across Atlantic Canada through the
weekend. Low pressure moving up the East Coast from the Southern
US becomes cut off and stalls south of New England, bringing an
extended period of unsettled and cool conditions. The low
likely doesn`t begin to move away until early next week as a
more progressive trough pushes in from the west.

Details...

As the low drifts northward, the high pressure will thwart its
progress and cause it to stall to the south. This sets up a
steady east-northeasterly flow that keeps much of northern New
England in a cool airmass from Friday through Sunday.
Additionally, waves of precip will be weakening as they approach
from the south starting Thursday night.

The first push of moisture approaches Thursday night, and will
be steadily weakening as it moves northward. Models, led by the
Euro, have been trending toward a drier solution during this
time period. POPs have been trended accordingly for the Thursday
night into Friday time period, with room to go lower so long as
the model trends continue. The day on Friday then looks mostly
dry, with the best chance for a shower across southern New
Hampshire, and the most sunshine likely across northern areas.

By later Friday night and Saturday, a more substantial push of
precipitation likely moves in as the low makes its closest pass.
Conditions will be cool enough for some snow, especially across
the interior and higher terrain, but precip type will likely be
more dependent on precip intensity, with snow confined more to
heavier rates. This precip shield will also be weakening as it
moves in, so there still remains much uncertainty on precip
type, as well as amounts.

The low continues to degrade to our south through Sunday and
into Monday, keeping the chance for showers around into Monday.
The best chance for these will be along the coast, with more
clearing expected through the day on Monday. With the clouds and
rounds of precip, temps start out cool early in the weekend
with highs in the 40s on Saturday. As more sun breaks through on
Sunday, highs likely recover back to the 50s, and then 60s
again by Monday. However, with any cut off low situation the
progression is far from certain from this far out, and these
systems have a history of moving more slowly than earlier
thinking. So we`ll continue to monitor the forecast over the
next few days, and won`t be surprised if the progression slows
down more over the next several model runs.

A more progressive trough likely swings into the Great Lakes by
the Tuesday to Wednesday timeframe next week, helping to clear
the last of the cut off low and bring in a drier westerly flow.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
Short Term...Any lingering flight restrictions due to -SN/low
ceilings will improve back to VFR within an hour or so of 12Z
this morning. Otherwise, VFR conditions can be expected today
with northwesterly wind gusts between 25-30 kts. Winds will
become light tonight with VFR prevailing. VFR will persist on
Thursday with developing southerly flow. No LLWS is anticipated
at this time.

Long Term...Some MVFR ceilings possible across southern
terminals Thursday night and Friday. MVFR to IFR conditions
likely arrive from south to north Friday night, with rain likely
south, and rain and snow likely across northern terminals. IFR
conditions likely linger through Saturday, with gradually more
breaks of MVFR ceilings from Saturday night through Sunday.
Conditions likely gradually return to VFR from west to east
Sunday night through Monday.

&&

.MARINE...
Short Term...Low pressure will exit well to the northeast of the
waters today with high pressure building in tonight through
Thursday. This will result in weakening winds and seas to below
SCA criteria later today.

Long Term...High pressure settles across the Canadian Maritimes
for Friday through the weekend, as low pressure stalls south of
New England. An extended period of SCA conditions are likely in
northeasterly winds from Friday night through Sunday. The low
then moves east by early next week.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$


NEAR TERM...Schroeter/Tubbs
SHORT TERM...Tubbs
LONG TERM...Clair/Ekster