Area Forecast Discussion
Issued by NWS Portland, ME-- Highlight Changed Discussion --
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FXUS61 KGYX 260133
Area Forecast Discussion
National Weather Service Gray ME
933 PM EDT Sat Mar 25 2017
A cold front stalls south of the region this evening. High
pressure builds in overnight from the north and will shift east
on Sunday. A warm front will approach from the southwest on
Sunday before a weak wave of low pressure forms and passes
through the Gulf of Maine Monday. This will provide a round of
mixed wintry precipitation Sunday night into Monday. Low
pressure moves north of the region on Tuesday and drags a cold
front through on Wednesday. High pressure will build in from
Canada for the end of the week.
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --920 pm Update: Skies have become clear across all forecast
areas, even across southern areas of NH/ME. There are a few
pockets of fog trying to form over southern/southeast NH where
precipitation occurred into the late afternoon. Will mention
patchy fog over southern areas. Light ventilation of dry air
from the north should help dry out low levels some and prevent
fog from becoming widespread the rest of the night.
620 pm update: Skies have cleared across all but southernmost
areas of NH which will occur in the next hour or so as rapid
clearing continues from the north. Made some adjustments to sky
cover for early this evening based on clearing trends. After
input of latest mesonet data no other changes were needed at
Bands of snow, some of them heavy will exit southern New
Hampshire over the next one to two hours. Thereafter, Canadian
high pressure will build southward, clearing skies across the
region. Cooler and drier air will be filtering south and into
Maine and New Hampshire. This will allow temperatures to fall
into the single numbers in the north with teens and 20s further
to the south.
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.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
Flow will become easterly on Sunday. This will allow for low
level moisture to enter coastal areas and also portions of
southern New Hampshire. Clouds will also be advecting into the
region from the next system. Cloud cover appearing after a cold,
clear night will keep some of the cooler readings in our region
for this time of the year with highs mainly in the upper 30s.
Sufficient easterly flow will allow for patchy drizzle to enter
the region at some point during the day Sunday. By Sunday
evening, synoptically driven precipitation will enter the region
as low pressure head towards the Great Lakes. Cold air damming
will continue however as high pressure remains to our north and
east. Expect a coastal front to develop as well.
Followed the cooler models for this package. Expect more in the
way of snow and sleet over central and northern areas with
freezing rain expected over southern and western New Hampshire
as well as coastal Maine just inland from the coastal front.
Some freezing rain may reach northern areas towards the long
range portion of the forecast.
Will update ice and snowfall maps to lean towards this cooler
solution. Temperatures Sunday night will likely hold fairly
QPF looks to be slightly over a half inch for much of our area
with several inches of snow over interior regions along with a
coating of ice.
.LONG TERM /MONDAY THROUGH SATURDAY/...
The models are in decent agreement on the longwave pattern into
late next week. We begin the period with a shortwave impulse over
the eastern Great Lakes. This impulse will weaken as it rides
northeast across New England Monday into Monday night. At the
surface...low pressure will ride northeast into Quebec with a warm
front moving into southern and western New England. Models strongly
hint that the warm front will hang up to our south with light
overrunning precipitation for Monday and Monday night. A series of
weak impulses will keep things unsettled for Tuesday. By Wednesday...digging
shortwave impulse will close off over New England with a continuation
of unsettled conditions. This low and associated surface system will
exit into the maritimes during Thursday...with lingering clouds and
showers confined to higher terrain as well as our eastern Maine
zones. Ridging arrives just in time for a quiet end to the work
week. Thereafter...considerable uncertainty exists in sensible
weather details as medium range models show considerable spread in
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
Short Term...VFR tonight. Conditions lowering to IFR and
localized LIFR by Sunday night. There could be some LLWS
developing Sunday night if the winds above the surface increase
Mon...IFR with lcl IFR in rain with areas of sleet and freezing
rain psb Mon at non-coastal taf sites.
Tue...MVFR with areas of IFR in ceilings, -shra and fog.
Wed - Thu...Areas of MVFR in -shra/-shsn.
NW sfc wind gusting to 25 kt.
Short Term...no flags.
Mon...Small Craft conditions are likely.
Wed - Thu...Small Craft conditions are likely.