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Area forecast discussion 
National Weather Service Gray ME
316 PM EDT Sat Oct 25 2014

Synopsis...
a cold front will cross the forecast area tonight followed by
gusty west winds for Sunday and Monday. High pressure builds in
late Monday. Low pressure approaches from the west Tuesday before
lifting north on Wednesday and dragging a cold front through New
England bringing colder temperatures for the end of the week.

&&

Near term /until 6 am tomorrow morning/...
a sunny pleasant day is in progress over a large portion of the
forecast area even as visible satellite shows dense cloud cover
over the New Hampshire/ME border along a warm front...and a large swath of
clouds from New York state west to the Great Lakes and north into
Canada. A few light returns are already showing up on radar in
association with the first boundary.

Deep depressions across the north are 10-20 degrees so it may take
a little bit for any of this to reach the ground. Expect any
showers to mostly affect the mountains and foothills where
orographic influence can interact with frontal forcing. Overnight
we may get a stray shower as far south as a Plymouth to Waterford
to Augusta line but it won't amount to much. A few flurries will
be more likely in the highest peaks as readings drop below 32...
but not expecting more than a few tenths. Cloud cover sticks
around for the most part helping keep lows in the 40s.

&&

Short term /6 am Sunday through 6 PM Monday/...
Sunday will be brisk with gusty west-northwest behind the front. Wrap around
moisture will keep upslope showers in the higher terrain
throughout the day. Temperatures will struggle out of the middle 40s
the north with some clearing across the coastal plain and readings
in the middle 50s.

High pressure begins to edge in from the west Sunday night.
Continued cold air advection and clearing skies will help
overnight lows drop into the 30s and 40s. More light flurries will
fall across the highest peaks.

&&

Long term /Sunday night through Saturday/...
the week starts out with a region of upper level ridging over the
area before another trough approaches from the Great Lakes
Tuesday. Monday morning will see upslope showers come to an end as
the surface flow shifts from northwesterly to calm and the high
crests overhead. That high pressure will result in clear skies and
cool temperatures for Monday night. Dewpoints remain relatively
high and should result in frost before temperatures drop too low.
Tuesday will see increasing clouds as the warm nose pushes into
the region. For coastal regions...this means flow right off the
water.. resulting in a marine stratus layer moving in by
afternoon. A cold front will move through the region on Wednesday.
Ahead of the front temperatures are quite warm... with 850mb temperature
at +13c...mean while, on the backside by 12z Thursday 850mb temperatures
are at -5c. This quick drop in temperatures will make the
Wednesday high temperature a bit tricky... more western areas may
see a sunrise high as the front almost immediately keeps
temperatures flat and downward. Meanwhile in the east along the
coast the surge of warm air ahead of the front will provide a
final last hurrah for the fall.

Behind the front cold air will remain in place as northern New
England sits on the eastern edge of the upper level trough. The
next system will rotate out of the Great Lakes for the end of the
week.



&&

Aviation /18z Saturday through Thursday/...
short term...showers will develop along first a warm front and
than a cold front as they near the region tonight and into
tomorrow morning. The majority of the forcing will be across the
mountains and foothills...but VFR or MVFR ceilings are possible at
all sites. Gusty west-northwest winds develop for tomorrow afternoon.

Long term... coastal sites will see ceilings lower to IFR as
marine stratus and fog moves in Tuesday afternoon. After a period
of IFR Wednesday conditions will return to VFR on
Wednesday...except at hie where upslope flow will once again
result in MVFR conditions.

&&

Marine...
short term...issued a Small Craft Advisory beginning late tonight
behind the cold frontal passage and lasting through Monday
morning. Marginal seas will skirt the outer waters...but winds
should reach 25 kts with strong cold air advection.

Long term...week will start out calm. After the cold front on
Wednesday strong gradient and cold air advection will combine to result in Small Craft Advisory
criteria for 12-18hrs following frontal passage.

&&

Climate...
coastal locations as well as Rockingham County have not yet had a
freeze or killing frost this fall. The median date of the first
fall freeze based on 30 years of climatology is October 11 for the
Maine and New Hampshire coastlines. It is now two weeks after
this date...therefore we will no longer issue products for freezes
or killing frosts for this area. This will conclude the
frost...freeze program for Maine and New Hampshire for the fall
season.

&&

Gyx watches/warnings/advisories...
ME...none.
New Hampshire...none.
Marine...none.

&&

$$

Hanes/Curtis

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