First Nor'Easter Of The Season Possible This Weekend

561

FXUS61 KGYX 222319

AFDGYX

Area Forecast Discussion

National Weather Service Gray ME

719 PM EDT Tue Sep 22 2026

.WHAT HAS CHANGED...

A frost advisory has been issued for parts of central New

Hampshire and western Maine for tonight.

&&

.KEY MESSAGES...

1. High pressure remains in control of the weather pattern

through late in the week.

2. A coastal storm may bring soaking rain, gusty winds, and high

surf from Friday through the upcoming weekend.

&&

.DISCUSSION...

KEY MESSAGE 1 DESCRIPTION...

High pressure continues to build across northern New England

over the next couple of days. This brings with it a seasonably

cool airmass, as well as some chances for frost tonight and

again Wednesday night. A frost advisory has been issued for a

few zones that are still active through central New Hampshire

and parts of western Maine. South of these areas, a

northeasterly breeze overnight keeps any frost isolated and

patchy. Tomorrow night looks cooler as the high pressure center

peaks overhead, so more areas of frost will be possible tomorrow

night as well. During the daytime, mainly sunny skies with

highs in the 60s continue.

While the high brings cool and fair weather to northern New

England, it also keeps a developing storm system off the

Carolinas to our south. The surf will start to build on

Wednesday as a long easterly fetch develops across the North

Atlantic between the high overhead and the developing storm

system. These waves will steadily build on Thursday and through

the end of the week bringing increasingly large breaking surf

and rip currents. Most land based impacts from the system hold

off until at least this weekend.

KEY MESSAGE 2 DESCRIPTION...

Starting Friday...An area of low pressure offshore of the Mid-

Atlantic is forecast to slowly lift northward and deepen Friday into

the first part of the weekend before stalling out and meandering for

at least the second half of the weekend. There`s slightly more

agreement within today`s ensembles in the northward extent the

low gets, but there continues to be a fair amount of spread in

how far offshore it remains or if there is a drift back west

before pulling away early next week. The majority of the

GEFS/AIGFS ensemble members are favoring the low center closer

to but still south or east of Cape Cod while the majority of the

ECMWF camp favors the low a bit farther to the west...south of

the southern New England coast. It should be noted that each of

these models also has multiple members that support the other

solution as well as some farther offshore, so a degree of

certainty exists.

Of higher confidence/less uncertainty: either way, the pressure

gradient will be tight across the region between the low and a high

to the north and west. So gusty north to northeast winds are

increasingly likely, especially along the coast. In addition to

this, a long fetch of these winds and swell will build seas over the

Gulf of Maine and bring the threat of high surf and a high risk of

rip currents at area beaches. This will also coincide with a period

of high astronomical tides, and given the increasing wind/wave

forecast, coastal flooding will be another possibility surrounding

the times of high tide.

Lesser confidence and more uncertainty is how much rain will

fall, but there is potential for soaking rain, especially along

the coast and portions of southern NH. NBM PoPs bring the

higher (low end likely) PoPs along the coast and into southeast

NH which is sufficient for the time being given the remaining

spread in the guidance. Temperatures may also stay in the 50s if

the rainier/cloudier scenario pans out.

The weekend conditions may carry into Monday, but ensembles

favor the low pulling away to the east by Tuesday of next week.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...

Through Wednesday...Widespread VFR conditions expected tonight.

Despite a light breeze I still think valley fog develops at both

LEB and HIE. Local IFR or lower conditions are expected thru

sunrise. VFR conditions will prevail again Wed with steady

northeast winds.

Outlook...

Friday: Mainly VFR.

Friday night-Sunday...Low pressure over the western Atlantic could

bring periods of MVFR ceilings and rain, especially along the coast

and southern NH. Visibilities may drop to IFR at times. In

addition, gusty north to northeast winds are possible.

&&

.MARINE...

An easterly swell continues to build over the next few days

while High pressure remains over the waters. SCA conditions

gradually spread north over the next couple of days, with waves

reaching 5ft starting across the southern waters by midday

Wednesday, and then expanding northward through Thursday.

Friday-Tuesday...Strong low pressure over the western Atlantic

and a high pressure to the north and west will result in a tight

pressure gradient over the waters. Although there is

uncertainty in where the low pressure center will be, increasing

north to northeast winds will likely result in at least SCA

conditions, but there`s increasing chances in seeing periods of

gales from Friday through the weekend and potentially into early

next week. Highest chances for gales will be outside of the

Bays and especially over the outer waters.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...

ME...Frost Advisory from midnight tonight to 7 AM EDT Wednesday for

     MEZ012-033.

NH...Frost Advisory from midnight tonight to 7 AM EDT Wednesday for

     NHZ003-004.

MARINE...Small Craft Advisory from 11 AM Wednesday to 8 PM EDT Thursday

     for ANZ154.

&&

$$

DISCUSSION...Clair/Combs

AVIATION...Legro

MARINE...Clair/Combs