Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 290433

Area Forecast Discussion
National Weather Service Gray ME
1133 PM EST Fri Feb 28 2020

Upper level low pressure slowly swings through New England
through the weekend. The result will be occasional mountain snow
showers and seasonably cool temperatures. We will see warmer air
move back into the region next week along with several chances
for precipitation. The best chance will be around midweek when
widespread rain is likely.


1130 PM Update...Little change to the going forecast for the
rest of the overnight. Mainly clear skies continue with
diminishing winds.

735 PM Update...Mostly clear skies continue most locations, with
bkn cloud cover and a few snow showers continuing in the
mountains. Winds continue to diminish as well. Therefore no
major changes to the going forecast.


Impacts: Occasional reductions in visibility in snow bands/showers
in northern NH and northwest ME.

Satellite imagery shows a large upper-level low spinning over
southern Ontario and Quebec. The ENE flow on the southeast side of
this feature has helped in producing lake effect snowfall to our
west...but we have also seen lake enhanced snow bands persist
through the day in northern NH and northwest ME, and these will
continue through the evening before mostly dissipating overnight.
Total accumulations should be rather light (2-3 inches at most) from
this afternoon through tomorrow morning with most of this falling
this evening. As mentioned above, visibilities in these
bands/showers has been reduced to 1 mile or less so caution is
advised if you find yourself driving through one.

Elsewhere, winds are still gusting to 25-30 mph this afternoon but
winds should gradually diminish as we head into the evening and
overnight hours. Skies will be partly to mostly cloudy outside the
mountains as low temperatures dip into the mid teens to lower 20s
along the coastal plain and into the single digits to lower teens in
the mountains.


Impacts: Minimal.

The upper-level low slowly moves east through the day on Saturday,
keeping skies cloudy in the mountains and partly to mostly cloudy
elsewhere. Again, snow showers will be possible in the mountains
with very light accumulations, if any, expected; these will also be
lesser in intensity than those on Friday. With the low passing just
to our north, high temperatures will be a few degrees cooler
compared to Friday. Skies will begin to clear south of the mountains
Saturday evening as the low continues moving off to the east,
becoming mostly clear by Sunday morning. Low temperatures will be
cooler than the previous night with the lack of cloud cover, ranging
from the single digits in the north to the mid teens in the south
and along the coast.


12Z model suite in relatively good agreement today in regards to
the large scale pattern late in the weekend. A weak ridge of
high pressure will slowly build east Sunday. This will allow for
northwesterly breezes to continue along with chilly
temperatures. Afternoon highs will likely only hold in the 20s
north to the lower 30s in the south.

As the ridge axis of high pressure shifts off the coastline
Monday night, a weak warm front will lift north as the winds
shift to the south. Warming temperatures will allow for a mix of
rain and snow showers that will continue into Tuesday morning,
albeit the precipitation will be relatively light within the
moisture starved system.

Models then diverge with some significance thereafter, yielding
a low certainty forecast.

It appears a weak system will eject into New England from the
fast moving southwest flow aloft late Tuesday into Tuesday
night. Even this timing appears to be different from model to
model, but a fast moving short wave may bring light
precipitation to the region with a mixture of snow and rain
showers across portions of the region.

Confidence deteriorates further midweek as a system attempts to
develop in the southeastern United States and shift towards New
England. Will lean towards a blend of solutions and previous
forecasts indicating the potential for precipitation late
Wednesday through Wednesday night. Euro and Canadian solutions
keep a system well south of our region, while the deterministic
and ensemble solutions within the GFS attempts to bring heavy
precipitation, mainly in the form of rain to the region. Have
paired down pops slightly from NBM in order to improve a blend
with adjacent offices.


Short Term...VFR conditions expected at all terminals through Saturday
night...except for slight chance for brief IFR conditions in -SHSN
at HIE on Saturday. Clouds will diminish somewhat tonight before
redeveloping on Saturday with similar ceilings as those seen today.
Gusty WSW winds will also come down this evening, and though it will
still be breezy on Saturday, gusts should be limited to 15 kt, still
out of the WSW.

Long Term...Mainly VFR conditions with the exception of a
passage of a warm front Monday night, allowing for some low
cloudiness and scattered rain/snow showers.

Conditions may lower once again during the midweek period with
one and possibly two systems approaching the forecast area from
the southwest.


Short Term...SCAs in effect for all waters this afternoon, but gusty
WSW winds will continue to diminish through this evening and
tonight. Waves will also continue to decrease and should be below
5 ft in all zones, except for the easternmost outer waters, by
late tomorrow morning.

Long Term...A brisk west to northwesterly gradient continues on
Sunday until an axis of high pressure shifts off the coastline
Monday. This will allow for a southwesterly flow to develop by
Monday night over the waters. A weak system may bring showers to
the region Tuesday or Tuesday night. There continues to be quite
a bit of uncertainty for a system to approach the waters during
the midweek period.


MARINE...Small Craft Advisory until 3 AM EST Saturday for ANZ150>152-


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