550
FXUS61 KGYX 210636
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
236 AM EDT Thu Aug 21 2025

.SYNOPSIS...
High pressure builds in from the north, allowing for fair
weather into Saturday with warming temperatures. Hurricane Erin
will pass well southeast of New England Friday with long period
swell from this system bringing high surf and dangerous rip
currents through Saturday. A slow moving cold front will cross
late Sunday into Monday likely bringing widespread showers.

&&

.NEAR TERM /THROUGH TODAY/...
Fog that developed overnight should dissipate in the early
morning hours for a mostly sunny day. Subsidence and a fairly
dry atmospheric column should keep skies mostly void of clouds
today, the exception may be along the coast where offshore
clouds pass.

With more uniform solar insolation, temperatures across vast
portion of the forecast area warm into the mid 70s. Light
easterly winds at the surface will keep RH values from becoming
too dry.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
Key Messages:
* High surf and dangerous rip currents are likely beginning
  Friday into the weekend with long period swell from Erin.
* Observing building surf should be done from a distance. Crashing
  waves into rocky bluffs can channel water, causing slips and
  falls.
* Wave action and surge combined with a high astronomical tide
  may bring minor coastal flooding surrounding the Friday
  evening high tide. Beach erosion and splash over may also
  result.

Clear skies and calm winds across the interior should lead to
another round of valley fog tonight. Higher clouds are possible
towards the coast associated with offshore systems.

Went lower on guidance for overnight temperatures given the
radiational cooling signal. Limitation may be some low level
winds keeping the surface mixed towards the coast and higher
points. Otherwise, another night of lower 50s to mid/upper 40s.

Weekend warmup begins Friday with temperatures pushing into the
low to mid 80s. NNE winds increase with gusts 15 to 20 mph in
the early to mid afternoon. The advection of warm but dry air
again keeps skies mostly sunny.

While wave period will already be increasing to 13 or 14 seconds
on Thursday, wave heights increase more readily during the day
Friday, nearing 10ft off the Midcoast. Wave action combined
with incoming surge will add to Friday evening`s already
elevated tide. This could lead to minor coastal flooding, beach
erosion, and splash over.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...

...LT Update... Erin will pass over the open North Atlantic on
Friday night as mid-level ridging begins to build over New
England. Saturday will feature mainly sunny skies and warm
temperatures into the 80s as H5 s/wv ridging crests overhead.
After a dry Saturday night and first half of Sunday, there will
be an increasing chance for showers by late Sunday as a cold
front approaches from the west. A period of beneficial steady
rainfall is then likely Sunday night into Monday as a trof of
low pressure swings across the region. Drier and cooler
conditions then look to return Tuesday through the end of next
week.

Previous Discussion...

Overview: High pressure over the Northeast will keep the forecast
area dry Friday and Saturday while Erin passes well southeast
of the Gulf of Maine. Long period swell from Erin will be
peaking Friday into Saturday bringing high surf and dangerous
rip currents to area beaches. A slow moving cold front will
likely bring some beneficial rain late Sunday through Monday. An
upper trough will linger over the Northeast through the middle
of next week maintaining chances for showers and temperatures
trending below normal.

Impacts:

*High surf and dangerous rip currents are likely into Saturday
 with long period swell from Erin diminishing early next week.

*Large near shore waves will likely cause some beach erosion and
bring the threat for splash over around the Friday night high tide.

Saturday will feature fair skies with warming temperatures as
high pressure will be over New England. Highs will be in the
mid 80s on Saturday. The forecast track of Hurricane Erin
remains well south and east of New England with the system
making its closest pass to the Gulf of Maine Friday morning. A
High Surf Advisory is in effect Friday and Saturday when long
period swell from Erin will be peaking at around 8 feet at 17
seconds. Large near shore waves of 7 to 10 feet will occur
around the time of the Friday night (11 PM EDT) high tide. Long
period swell will diminish late Saturday into Sunday.

Clouds will increase from west to east Sunday as a slow moving cold
front approaches from the Great Lakes. There will also be a gradual
increase in shower chances while the bulk of the precipitation
associated with the front will hold off until Sunday night and
Monday. Ensembles show a strong signal for a widespread wetting
rainfall with the latest NBM coming in with higher PoPs Sunday night
and Monday. There continues to be a spread in QPF amounts with
ensemble means remaining near 0.25 to 0.5 inches by Monday night.
Overall, this system is looking to bring some beneficial
rainfall while it may not put too much of a dent into ongoing
deficits that have been building this summer. Troughing will
remain west of the area through mid week with embedded short
waves rotating through bringing additional chances for showers.
As the trough slowly slides east temperatures will trend below
normal going into the second half of next week.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Short Term...VFR today after any morning fog dissipates by 14z.
Steady E winds arrive along the coast and interior this morning
through afternoon. Additional fog development possible tonight,
otherwise VFR continues through Friday.

Long Term...Mainly VFR into Sunday. Some restrictions will
become possible Sunday night into Monday as a front brings
widespread showers.

&&

.MARINE...
Short Term...Seas begin to build, but are expected to stay
below SCA levels until this afternoon/evening when the larger
swells from distant Hurricane Erin arrive. Winds will be out of
the ENE/NE today, but then become NE/NNE overnight as Erin
moves to the northeast over the western Atlantic. Gusts to
around 20-25 kt will be possible over the outer waters tonight
as seas also continue to build. SCA conditions are expected
Friday.

Long Term...Long period swell from Erin will subside late
Saturday through Sunday. Steady NE winds Friday morning will
relax and shift out of the south Saturday. Southerly winds ahead
of a cold front may bring a return SCA conditions Sunday
afternoon.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...High Risk for Rip Currents from 6 AM EDT this morning through this
     evening for MEZ023>027.
     High Surf Advisory from 6 AM Friday to 8 PM EDT Saturday for
     MEZ023>028.
NH...High Risk for Rip Currents from 6 AM EDT this morning through this
     evening for NHZ014.
     High Surf Advisory from 6 AM Friday to 8 PM EDT Saturday for
     NHZ014.
MARINE...Small Craft Advisory from 2 PM this afternoon to 8 PM EDT
     Saturday for ANZ150-152.
     Small Craft Advisory from 8 PM this evening to 8 PM EDT
     Saturday for ANZ151-154.
     Small Craft Advisory from 2 AM Friday to 8 PM EDT Saturday for
     ANZ153.

&&

$$


NEAR TERM...Cornwell
SHORT TERM...Cornwell
LONG TERM...Schroeter/Tubbs