Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 230223

Area Forecast Discussion
National Weather Service Gray ME
1023 PM EDT Thu Mar 22 2018

Low pressure tracks northeast through the Canadian Maritimes
tonight. The area will remain cooler than normal through the
weekend. A passing front Saturday night and Sunday will bring
snow showers, and possibly light accumulations, to much of the
area. To start next week high pressure noses in and will start
to moderate temperatures to readings at or above normal for


1015 PM...This update just brings POPs way down through tonight
as precip looks to be over with a clear radar image. Temps
falling rather slowly in many spots as some wind continues, but
should see a period of rad cooling after midnight and temps may
fall off more quickly then, especially given current Tds in the
upper teens to mid 20s. I did hedge mins up by just a bit.

635 PM...Although a few flurries /or even sprinkles/ will be
possible along the coast through about 8 or 9 pm, it will
continue to dry out this evening. Models continue to show winds
decoupling inland areas, and though they are diminishing now,
they are far from light/variable in most places. How much will
decoupling will affect lows, especially in the elevated valleys
tonight, which could mean the difference between lows around 10
and lows around 20 in inland spots. For now played the middle
of the road with the mins.

Previously...Low pressure currently centered 41 N 65W, well
east and south of the Gulf of Maine. North to northeasterly flow
remains in place across the area. The remaining few snow
showers affecting the midcoast through Penobscot bay will
gradually come to an end this afternoon as the low continues to
move east. Clearing skies are expected through the evening as
even the cirrus from the storm moves to the east. Have dropped
temperatures a bit across the northern mountain valleys where
radiational cooling may be able to take hold overnight.


Upper level low moves into place overhead through the day on
Friday. Expect increasing clouds and snow showers in the north
country as the upslope flow develops. Towards Friday afternoon
an upper level disturbance will help to touch off some snow
showers or squalls. The greatest instability is to the west of
our region but a few squalls may make it into the Connecticut
River valley tomorrow afternoon.

With mainly sunny skies across the coastal plain, temperatures
will be able to climb into the mid 40s across most of the


There are a couple of wx highlights in the extended...and were
the focus of this forecast.

The first is Sat night/Sun when a S/WV trof will pinwheel around
the larger upper low and cross the region. A saturated snow
growth zone and at least some weak lift is likely as it passes.
With a pocket of colder temps aloft...we may even be able to
generate some instability to help accelerate vertical motion. I
am expecting snow shower activity could be pretty widespread
along the trof...with light accumulations possible. Trying to
pin down the axis of the surface trof at this range is I preferred PoP values in the high chance/low
likely range.

As we turn towards next week...model guidance is forecast low
pressure to cut off in the Wrn Atlantic...with ridging rolling
over the top of it. That would place the forecast area in a
favorable zone for dry and warm wx. Ensemble guidance is already
showing some larger standardized anomalies for this range as the
ridge builds in. I blended in a little more MOS guidance to the
middle of next week to account for the warmer look.


Short Term... A few MVFR ceilings hanging on along with the
snow showers along the coast should move out in the next few
hours with VFR expected through Friday morning.

Long Term...A passing trof Sat night into Sun may bring
widespread SHSN to the area. Areas of IFR/LIFR conditions are
possible at all terminals. SHSN will taper off Sun
afternoon...with VFR conditions taking over thru midweek.


Short Term...Have dropped the Gales in favor of SCA as the
coastal storm continues to pull out of our region.

Long Term...Off shore flow will continue behind low pressure.
SCA conditions will prevail...and on Sun behind passing trof a
few gale force gusts are possible. SCA conditions linger into
early next week.


Minor splashover possible in the next hour around the time of
high tide.


MARINE...Small Craft Advisory until 8 AM EDT Friday for ANZ150>152-154.


NEAR TERM...Cempa/Curtis
LONG TERM...Curtis/Legro
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