Area Forecast Discussion
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FXUS61 KGYX 151942
Area Forecast Discussion
National Weather Service Gray ME
242 PM EST Sun Jan 15 2017
High pressure builds in tonight and Monday, then shifts east on
Tuesday. Low pressure crosses the region Tuesday night into
Wednesday night and will bring a mix of snow and rain to the area.
High pressure builds in at the end of the week, with above normal
.NEAR TERM /THROUGH TONIGHT/...
Mainly clear skies over southern areas tonight, with, once again,
more cloudiness in the north and mountains. A couple of weak, but
fast moving short waves will allow for some Cirrus over northern
areas. Also, some upslope cu may become trapped under the
inversion tonight in the higher terrain. This will once again
allow for a wide range of overnight mins that will be very
dependent on the cloud cover. Some areas will radiate under clear
skies and light winds.
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
High pressure will crest over the region early Monday before
heading out to sea. A weak weather disturbance well north of Maine
will allow for a wind shift over northern areas later in the day.
However this system is very moisture starved, with little impact
in our region.
High pressure over Eastern Canada will reassert itself Monday
night, setting up cold, dry air in northern New England as a
system approaches from the Midwest. Some high thin cloudiness will
be approaching the region Monday night, setting the stage for
precipitation entering for the long term portion of the forecast.
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Over the past day...models have come into better agreement on the
longwave pattern through the upcoming weekend. We begin with a low
amplitude split flow regime that transitions to a high amplitude
regime featuring a deep trough over the western CONUS with a
downstream ridge here in the eastern CONUS. While longwave pattern
is in better agreement...we continue to see differences in
shortwave strength and timing...particularly early in the
forecast period. Overall...the northern stream will keep arctic
air bottled up to our north and we`ll see temperatures average
above normal for the period. In the dailies...a ridge of high
pressure will retreat offshore on Tuesday. A shortwave impulse and
associated surface low approach from the Great Lakes for Tuesday
night and Wednesday with a secondary low advertised to develop
late Wednesday over southeast coastal New England. With models now
putting more emphasis on the secondary low...we`re trending colder
both surface and aloft increasing the likelihood of more white
then wet or freezing...especially across the mountains and
foothills. For Wednesday night into Thursday...proximity of the
upper trough and a surface trough extending northwest into the
region from the offshore low support lingering snow or snow
showers and at least some light additional accumulations. A ridge
of high pressure should then slide east across the region for
Friday and much of the upcoming weekend.
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
Short Term...VFR conditions through Monday night with some high,
thin cirrus in the mountains as well as upslope Cu.
Tue night - Wed...IFR in SN/PL/RA with areas of LIFR.
Thu...areas of MVFR in shsn.
Short Term...Winds continue to gradually diminish. Will be
lowering the SCAs with this package.
Wed - Thu...Small craft conditions are likely...With gale force
possible gusts outside the bays.
Fri...Small Craft conditions are possible.