Area Forecast Discussion
Issued by NWS Portland, ME

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295
FXUS61 KGYX 220622
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
222 AM EDT Fri Aug 22 2025

.SYNOPSIS...
High pressure will maintain fair weather over the region into
the weekend. Long period swell from distant Hurricane Erin will
continue to build into the weekend and will be slow to subside
early next week. A slow moving cold front will bring increasing
chances for showers late Sunday into Monday. Troughing will
linger over the Northeast through the middle of next week.

&&

.NEAR TERM /THROUGH TODAY/...
Key Messages:
* Swell has arrived from Hurricane Erin. Combined with
  increasing wave heights, this will create high surf and
  dangerous rip currents along the coast today through
  Saturday.

Dry weather continues with sunny skies today. Some cirrus from
Hurricane Erin in the open Atlantic may be observed early this
morning, but this should pull offshore as the day progresses.

Between incoming high pressure ridging and Erin, pressure
gradient overhead will be enough for a northerly breeze this
afternoon. Given daytime heating, this mixing will be enough to
bring down some dry air aloft, causing lower RH values. Adjusted
dewpoint temps down from NBM by mixing to 800mb.

Warmer today with highs into the lower 80s, but still plenty
comfortable given the lack of much humidity. Interior temps
warming should bring a seabreeze inland through the afternoon.
Should background northerly winds remain a factor, how far
inland may be limited.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM SATURDAY/...
Key Messages:
* High surf and high rip current risk continues Saturday, but a
  slow decrease in wave heights is forecast.
* Wave action, surge, and a high astronomical tide cycle will
  bring the threat for beach erosion, splash over, and minor
  coastal flooding during the Friday night high tide. See
  Tides/Coastal Flooding sections for more information.

A few additional clouds tonight and warmer. Still expect low
lying spots to radiate pretty well with lows into the upper 40s
once again. Otherwise, lows generally fall into the mid to lower
50s.

Upper level ridge crests Saturday with the low levels beginning
gentle SW flow and moisture advection. Precip will hold off, but
an increase in clouds will be noticeable vs. the second half of
the week.

Temperatures likely peak here for the week with highs pushing
into the mid 80s. Winds at the surface will have shifted
southerly, becoming breezy in the afternoon. This southerly
flow will have a bit more moisture with it, with not as dry RH
values vs. Friday.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
...LT Update... Mid-level s/wv ridging will begin to exit to
our east on Saturday night ahead of an area of low pressure that
will be crossing over Quebec. Clouds will gradually increase
overnight and a few showers are possible across the north and
mountains overnight with low temperatures within a few degrees
either side of 60. Clouds will continue to increase on Sunday
with shower chances gradually sinking south through the day as
closed low pressure over Quebec sends a sfc cold front eastward.
High temperatures will be into the 70s to lower 80s. A weak
secondary area of low pressure is then progged to form along
this front Sunday night into Monday, bringing our best potential
for more widespread rainfall of the entire forecast period.
Rain chances will then diminish Monday night into Tuesday but a
few wrap-around showers are possible across the higher terrain
and far north. Trofing then looks to persist through much of the
remainder of the week with temperatures a little below avg and
little in the way of additional rain chances.

Previous Discussion...
High pressure moves east Sunday as a trough deepens over the
Great Lakes. This trough will slowly migrate east through the
middle of next week and will send a frontal system across New
England late Sunday through Monday. Cyclonic flow aloft will
linger through the end of the period that will maintain low
chances for showers with a cooling trend into next Wednesday.

Sunday looks to remain mostly dry as a frontal system over the
Great Lakes will be slow to move east. Southerly winds will
become breezy Sunday, especially along the coast towards central
Maine where gusts will approach 30 mph. Clouds and rainfall
chances will increase west to east late Sunday with showers
likely Sunday night through Monday. Ensembles continue to
suggest much of the area will see measurable rainfall, while
even the high end QPF members suggest this rainfall will do
little to reduce the precipitation deficits that have been
building over the past two month.

Th trough axis will remain west of New England Tuesday with
embedded waves bringing continued chances of showers. The trough
will move overhead Wednesday for a cooling and drying trend. The
latest round of NWP guidance suggest the trough will linger
through the end of next week with additional waves rotating
through the trough that could bring additional chances for
showers.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Short Term...Mainly VFR through tonight with some valley fog at
HIE/LEB and through southern ME. Northerly winds pick up today,
but will see a wind shift for coastal terminals where sea breeze
comes through this afternoon. Southerly winds for Saturday, with
some gusts 15 to 20 kt.

Long Term...Mainly VFR into Sunday. A cold front crosses late
Sunday and Monday with lowering cigs and showers bringing the
potential for at least MVFR conditions. Strong southerly flow
ahead of the front will also bring the threat of wind shear
Sunday into Monday morning.

&&

.MARINE...
Short Term...Large, long-period swells from Hurricane Erin
continue to build over the waters and bays. There may also be a
period of north to northeast winds gusting to around 25 kt
into this morning, mainly over the outer waters. SCA conditions
persist through Saturday as wave heights are slow to decrease
behind Erin`s departure.

Long Term...Long period swell from Erin will be on the downward
trend as seas will continue to run above 5 feet into Sunday.
Southerly flow ahead of a cold front will ramp up Sunday with
wind gusts likely continuing SCA conditions into Sunday night.
Winds and seas drop below SCA thresholds Monday.

&&

.TIDES/COASTAL FLOODING...
High astronomical tides and up to 2 feet of storm surge may
produce minor coastal flooding and splash-over during the late
evening high tide tonight, and a Coastal Flood Advisory has
been issued.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...High Surf Advisory from 6 AM this morning to 8 PM EDT Saturday
     for MEZ023>028.
     Coastal Flood Advisory from 10 PM this evening to 1 AM EDT
     Saturday for MEZ023>028.
NH...High Surf Advisory from 6 AM this morning to 8 PM EDT Saturday
     for NHZ014.
     Coastal Flood Advisory from 10 PM this evening to 1 AM EDT
     Saturday for NHZ014.
MARINE...Small Craft Advisory until 8 PM EDT Saturday for ANZ150>152-
     154.
     Small Craft Advisory until 8 PM EDT Saturday for ANZ153.

&&

$$


NEAR TERM...Cornwell
SHORT TERM...Cornwell
LONG TERM...Schroeter/Tubbs
TIDES/COASTAL FLOODING...Combs