Area Forecast Discussion
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FXUS61 KGYX 250749
Area Forecast Discussion
National Weather Service Gray ME
349 AM EDT Sun Sep 25 2016
High pressure moving out of Canada will bring cooler temperatures
and drier air to the region through tonight. Most towns in the
area will see their first frost or freezing temperatures tonight.
Gradually moderating temperatures are expected Monday before
another approaching cold front brings the threat for showers for
Monday night and Tuesday. Drier weather returns for midweek.
.NEAR TERM /THROUGH TODAY/...
Current freeze warnings and frost advisories will expire at 8 am
this morning. Whitefield NH currently has the coldest reported temp
with 31, but expect many valley locations will have dropped to or
below freezing by morning.
As the area of high pressure continues to push into the region
today, skies will be mostly sunny with late morning and afternoon
fair weather cumulus. In eastern sections, there will be some mid
to high level clouds dropping southeast on the back side of the
upper level trough.
High temps today will range from the mid 50s north to the mid 60s
.SHORT TERM /TONIGHT THROUGH 6 PM MONDAY/...
The ridge of high pressure moves overhead tonight and temps will
drop rapidly as the winds diminish. Currently expecting freezing
temperatures across northern sections and widespread frost across
much of the area. Low temps tonight will likely drop to the mid
20s in the colder locations in the mountains and will range to
near 40 along the immediate coast. Will be allowing current freeze
warnings and frost advisories to expire this morning and allow the
day shift to issues new warnings and advisories for tonight.
The high moves east Monday allowing slightly warmer temps. A cold
front approaching from the west will start to spread high clouds
into western sections during Monday afternoon. After a cold start
tomorrow morning, highs will be mainly in the 60s across the area.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Deterministic models are coming more in line as far as timing...at
least early on in the extended. There is still much uncertainty
after Thursday. Whether rain showers reach our area will depend on
if the 1025mb Canadian high pressure can suppress a baroclinic
zone as it attempts to move north.
In the dailies, a coastal low develops Tuesday night and ejects
towards the Canadian maritimes. The upper low located over the
Great Lakes begins to fill and drifts south, eventually spinning
towards the mid Atlantic region and stalling do to blocking
downstream. Offshore...the front which moved through Tuesday night
This is a low confidence forecast from Thursday onward. Wednesday
and part of Thursday look dry for the most part as dense Canadian
high pressure spills across the Central Plains and into the
northeast. Clouds will return Thursday after clearing out behind
the cold front. Rain showers may also return on Thursday
especially over the south and remain in the forecast through
Saturday. Have kept PoPs generally on the low side during this
time until there is more agreement among the guidance.
There will be a cooling trend during this time with highs ranging
from the upper 50s north to near 70s south. Overnight lows will
be warmer so not expecting any more freezes after Monday morning.
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
Short Term...VFR conditions expected except for patchy early
morning fog in the Connecticut River Valley and patchy freezing
fog in the northern river valleys this morning and again Monday
Long Term...MVFR or IFR conditions in showers (which may be heavy
at times) will occur Tuesday as a cold front and possibly a
coastal low develop and sweep east. Low level moisture may remain
trapped under an inversion and cause patchy fog Wednesday morning
before skies lift. Morning fog will again be possible at LEB and
HIE Thursday morning.
Short Term...Winds and seas expected to generally be below SCA
criteria, although a few gusts could reach near 25 kts this
afternoon and seas may approach 5 feet well offshore.
Long Term...Prolonged southerly fetch over the waters may push
wave heights into the 5-6 ft range with a few gusts over 25 kts.
Should see conditions calm down again on Wednesday with high
pressure moving toward the area. There is a high degree of
uncertainty in the forecast from Thursday onward with winds
generally from the NNE at 10 to 15 KT the most likely result.
It is possible that low pressure could form over the waters
Tuesday night bringing more of an southerly component to the
winds and perhaps some stronger wind speeds and higher wave
ME...Freeze Warning until 8 AM EDT this morning for MEZ007-008.
Frost Advisory until 8 AM EDT this morning for MEZ009-012-013.
NH...Freeze Warning until 8 AM EDT this morning for NHZ001-002.
Frost Advisory until 8 AM EDT this morning for NHZ003-004.