Belfast, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

407
FXUS61 KGYX 220845
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
445 AM EDT Thu May 22 2025

.SYNOPSIS...
A late season nor`easter is strengthening this morning and will
be with us through at least Friday. Rain will overspread the
area today, and as we head into the overnight snow will begin to
mix in across the mountains. Winds will start to lash the coast,
with northeast gusts up to 45 mph at times. As if the forecast
could not get worse, the storm is expected to cut off and slowly
drift across the region through Saturday. That will continue
showery weather. Finally high pressure will begin to build in
Sunday and eventually warmer and brighter conditions return next
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Low pressure is beginning to take shape as the upper forcing
crosses the Mid Atlantic and precip shield consolidates south of
New England. That will steadily expand northeastward today...but
with lingering influence of departing high pressure that may be
a slow march across the forecast area. It may take until mid
afternoon to reach parts of western ME.

Deep onshore flow and plenty of clouds and precip/evaporational
cooling it will be a struggle for temps to climb much. Topping
out around 50 may be a stretch. The record cold high temp for
the day is a bit of a warm one surrounded by cooler days...with
PWM 50 in 2011 and CON 51 in 1939. These records are very much
in play today...and not the kind of record we are looking to
set.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Storm will reach peak intensity tonight. The strongest winds
will be skirting the coastline at this time. Northeast gusts
will generally be between 30 and 40 kt...but with full leaf out
it may not take much for limbs to come down and power outages to
result. The wind advisory remains in effect for all coastal
zones.

This is also the period when the strongest dynamic cooling will
be occurring under strong lift. In addition precip melting thru
the column will also help to cool things into the 30s at
elevation. Forecast temp profiles are near isothermal around
freezing above about 1500 feet. So I anticipate some
accumulation above that level. I have my eye mostly on the
Monadnock region...where some power infrastructure exists in
that elevation range. A 2 to 3 inch snowfall after leaf out
could be enough to take down some limbs.

The storm will begin to occlude into Fri morning and precip
intensity will start to diminish as dry slot pushes into the
area. Snow in the mtns may begin to mix...but overall it will be
a pretty wintry day in the high peaks. Elsewhere it will likely
stay in the 40s. By the end of the day precip will be tapering
to showers.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Long term Update...01z NBM has been blended in and doesn`t
result in much in the way of changes in the long term. While dry
period will be had early to mid week it will still remain
relatively unsettled.

Overview...

Low pressure slowly moves east of New England on Saturday, with the
upper level low lagging behind and not fully exiting until Monday. A
moderating trend returns early to midweek next week as ridging
builds eastward across New England. At the same time, a cut off
upper level low likely deepens across the Great Lakes, and may
approach New England by late next week.

Details...

The slow moving low pressure center will drift through the Gulf of
Maine Friday night and into the Canadian Maritimes on Saturday. The
upper level low follows in it`s tracks, keeping bands of light rain
and showers moving through northern New England on Saturday. The
most widespread coverage of rain will be across the higher terrain
and northern areas on Saturday. Scattered shower activity is more
likely across the rest of the forecast area, with an uptick in
coverage across western areas during the afternoon hours as the
upper level low increases the shower activity.

The upper level low center moves into the Canadian Maritimes on
Sunday, with a lingering trough across New England behind it. This
makes for a brighter and warmer day overall, but some pop up shower
activity is likely across the higher terrain during the afternoon
with the cold air aloft. Outside of the mountains, temperatures
begin to rebound, likely reaching into the low to mid 60s. With more
clouds and some showers, northern areas and the higher terrain
likely remain in the low to mid 50s.

By Monday, ridging begins to build in from the west, with high
pressure also building in from the west at the surface. This
continues the moderating trend, with highs warming into the 60s to
low 70s with increased sunshine. The coverage of 70s expands on
Tuesday across the area. The high pressure center moves offshore by
midweek, providing the set up for a steadier sea breeze. At the same
time, a deepening cut off low across the Great Lakes likely begins
to approach and continue moving closer toward the end of the week.
This brings an increasing chance for showers and cooler temps toward
the end of the week, but will be highly dependent on the track of
the cut off low. Should the low end up further south, ridging would
remain in place and warmer temperatures continue, so we`ll continue
to monitor the progress of this feature over the next several days.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
Short Term...Widespread MVFR conditions this morning as onshore
winds continue to carry moisture inland. CIGs will lower thru
the day as rain also moves in from southwest to northeast. Areas
of IFR will begin to develop late this afternoon and early this
evening and expand northeast thru the night. Near the coast
northeast gusts up to 35 or 40 kt are possible overnight. This
will also be when some of the heaviest precip occurs...and VIS
may fall to IFR at times. Some gradual improvement in
conditions is expected Fri...especially across southwest zones.

Long Term...Lingering IFR to MVFR conditions generally improve
toward more MVFR ceilings on Saturday, with IFR most likely at HIE.
Gradual improvement back to VFR is likely on Sunday, with MVFR
ceilings most likely at HIE. VFR prevails during at least the
daytime Monday through Wednesday, with nighttime valley fog
possible each night.

&&

.MARINE...
Short Term...As low pressure deepens today...winds and seas will
increase thru the overnight. Strong gales are expected for all
waters...and seas outside of the bays will build in excess of 12
feet. Once the storm reaches peak intensity and begins to slowly
drift away...winds and seas will begin to diminish Friday
afternoon.

Long Term...Seas gradually drop below 5ft on Saturday as low
pressure slowly moves away through the Canadian Maritimes. High
pressure then gradually builds across the waters early to mid week
next week, bringing fair conditions.

&&

.TIDES/COASTAL FLOODING...
As winds and seas increase today they will begin to drive a
growing storm surge thru tonight. Guidance is forecasting a
surge somewhere between 1 and 2 ft...peaking around or
after midnight. The good news is that this is going to occur
closer to low tide than high tide. However water levels
approaching action stage and large near-shore waves could lead
to splash over at the more vulnerable coastal locations.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Wind Advisory from 2 PM this afternoon to 7 AM EDT Friday for
     MEZ023>028.
NH...Wind Advisory from 2 PM this afternoon to 7 AM EDT Friday for
     NHZ014.
MARINE...Gale Warning from 2 PM this afternoon to noon EDT Friday for
     ANZ150>154.

&&

$$

NEAR TERM...Legro
SHORT TERM...Legro
LONG TERM...Clair/Ekster
AVIATION...Legro
MARINE...Legro