Area Forecast Discussion
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FXUS61 KGYX 210145
Area Forecast Discussion
National Weather Service Gray ME
945 PM EDT Mon Mar 20 2017
A cold front will approach front the northwest overnight and
will drop south through the region on Tuesday. A secondary
arctic front will push south through the region Tuesday. High
pressure will gradually build in from the west Wednesday through
Thursday. High pressure will sift offshore Thursday night. A
cold front will approach from the northwest on Friday and will
push south through the region Friday night. High pressure will
build in from the north Saturday through Sunday.
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
10 Pm Update...Have adjusted the forecast a little bit, mainly
for sky and temps. Increasing mid clouds in the far west should
continue overnight. Otherwise, keep up with temperatures in
areas that are radiating.
7 PM Update...Pleasant evening continues. Just some thin cirrus
overspreading the region at this time. Otherwise, temperatures
should drop fairly quickly this evening with light winds in
It looks most quietly overnight, with cirrus begin to move in
from the west and lower and thicken, especially over NH zones.
Winds will continue to diminish and should become light/var a
few hours after sunset, so will see some decoupling. The
question for tonight is how low will temps fall before the
clouds move in and stop the rad cooling. It`s likely that ern
zones will see the best rad cooling, and mins should fall into
the 20-25 range in these areas, with most other spots dropping
into the mid to upper 20s. There an outside chance of a few
flurries in the mountains late.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Cold front will approach from the NW during the morning, and
clouds will linger over the mountains /although some breaks of
sun are possible in the morning/. Across the srn 2/3 of the CWA
should see a period of partly to mostly sunny skies form mid
morning thru early afternoon before clouds thicken up, ahead of
the front. Airmass remains very dry but could see some sct -SHSN
of -SHRA in the nrn zones by mid afternoon afternoon, although
they may be widely scattered, and may move down toward the
coast late afternoon or early evening. Highs will reach we into
the 40s on the coastal plain and in srn NH and in the 40-45
range in the north.
As is often the case in New England, cold front never come
through simply, and a weak wave developing along the front Tue
night, will weaken it the front, and shift the best forcing
aloft to the east, and will have to wait for secondary front to
come through behind the low late Tue night or early Wed. So
temps will fall off to the teen to mid 20s from N to S, with the
coldest air moving on increasingly gusty winds during the pre-
dawn hours, when temps will fall rapidly thru sunrise.
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
High pressure will build into the region from the west on
Wednesday as upper trough swings through the northeast. Expect a
mix of sun and clouds through the day. Tight pressure gradient
will result in a blustery day with temperatures once again well
below normal. Highs will range from the mid teens to lower 20s
north and mid 20s to near 30 south.
High pressure will continue to build in from the west Wednesday
night and Thursday. Looking for clearing downwind of the
mountains and variable clouds in the north Wednesday night with
lows ranging through the single numbers to the lower teens.
Thursday looking mostly sunny with less wind. Highs will range
through the 20s to the lower 30s.
Broad area of over-running will shift in from the west ahead of
an approaching cold front Thursday night. Looking for increasing
clouds with a chance of a snow shower in northern zones toward
daybreak on Friday. Lows will generally range through the teens.
Weak warm frontal boundary will push in from the west on Friday
producing a variety of precipitation during the day. Occasional
light snow will gradually go over to rain in southern zones as
boundary layer temps warm above freezing. Farther north snow will
mix with sleet and rain during the afternoon. In any case expect
QPF amounts on the light side with generally a tenth of an inch
or less through the end of the day. Highs will range through the
mid 30s to lower 40s north and lower to mid 40s south.
A cold front will drop south through the region Friday night.
Expect evening rain showers to transition back to snow showers
in the north. Rain showers in the south may mix with or change
over to snow toward Saturday morning before ending. Once again
QPF overnight will be on the light side with amounts of a tenth
of an inch or less.
Skies will gradually clear on Saturday as the front pushes south
of the region and high pressure builds in from the north. Not a
lot of cold air behind the front so high temps will top out at or
above normal. Readings will range from the mid 30s to mid 40s
north and mid 40s to mid 50s south. High pressure will remain in
control over the area Saturday night and Sunday. Stalled frontal
boundary to the south of the area will begin to lift north Sunday
afternoon and will likely push some clouds into southern New
Hampshire by evening but at this point the day should remain dry.
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Short Term...Could see a period of MVFR conds Tue afternoon,
and lingering through Tue night at KHIE. Otherwise VFR expected
through Tue night.
Long Term...VFR Wednesday through Thursday night. Areas of MVFR
ceilings Friday and Friday night. VFR Saturday.
Short Term...Winds have generally fallen below SCA levels, but
seas will remain up outside of the bay through tonight, so have
converted to SCA for haz seas, as swell from offshore storm
slowly dissipates tonight. Winds will pick up quickly behind a
cold front late Tue night, and may reach SCA before daybreak
Long Term...Gales likely on Wednesday.
MARINE...Gale Watch from Wednesday morning through Thursday morning for
Small Craft Advisory for hazardous seas until 8 AM EDT Tuesday