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Area forecast discussion 
National Weather Service Gray ME
927 am EDT Wednesday Sep 17 2014

Synopsis...
a cold front will approach from the north today and will push
south through the region late tonight and early Thursday. The
front will produce little in the way of rain showers...but
temperatures will drop sharply behind the front late Thursday and
Thursday night. High pressure will build in from the west
Thursday night and will crest over the region early Friday before
shifting offshore. A warm front crosses the region on
Saturday...pushing temperatures above normal Sunday and Monday.
A cold front moves through Monday night and cools things back
down by the middle of next week.

&&

Near term /through tonight/...
update...
have updated the grids based on current conditions. The fog is
slow to burn off in the CT River Valley and some of the foothills
in Maine. Will delay improving conditions in the grids and tafs.
Have adjusted dew point values upwards for this morning.

Monitoring the progression of our next cold shot. We are
anticipating frost and freeze conditions for the northern 2/3 of
our forecast area Thursday night.

Previous disc...
areas of valley fog will burn off through middle morning
and the region should see a mostly sunny Wednesday. Cold front
dropping south from Quebec may push some middle level clouds into
northern zones this afternoon but not looking for any precipitation. High
temperatures will range through the 60s to near 70 in the south.
Developing sea breeze will cap temperatures at the coast.

&&

Short term /Thursday/...
cold front will slowly drop south through the region tonight. Not
expecting much more than variable middle level clouds for most
areas. Can't rule out a shower or sprinkle in the mountains but
these should be few and far between. Low temperatures will range from the
upper 30s to lower 40s north and in the middle 40s to near 50 south.'

Cold front shifts offshore early Thursday followed by high
pressure building in from the west. Morning clouds will gradually
give way to mostly sunny skies. Northwest winds will be on the
increase during the late morning and early afternoon. High temperatures
will be similar to today before dropping off sharply in the late
afternoon and evening.

&&

Long term /Thursday night through Tuesday/...
surface high builds in Thursday night below zonal flow at 500mb and 850mb
temperatures between 0 and -4c. This will make for a cold night...with a
good shot at a hard freeze in the mountain zones...where mins should
fall to the upper 20s to around 30. A killing frost in the
foothills....and will likely see some frost all the way into the
inland coastal zones....as mins will be in the 30s. Even coastal
areas could see some reading in the upper 30s.

The surface high shifts eastward across the County Warning Area Friday...which will allow for
weak onshore flow to develop...and this combined with cold air
aloft will keep maximum temperatures mainly in the 50s across most of the
County Warning Area...although a few of the warmer spots could make it to 60 or
so. Despite mainly sunny skies...it will still be chilly.

Will start to see SW flow develop Friday night...and intensifypretty
good at the middle levels...which will quickly warm things up at
850mb. Will see more in the way of clouds over the mountains Saturday
as the middle-level warm air advection gets going...but precipitation looks to hold off until
Sat night associated with surface warm front. Highs get closer to
normal on Sat mainly in the 60s. Clouds and showers Sat
night...especially in the north will keep mins on the relative warm
side...in the 50s. A little bit of weak ridging builds in for
Sunday with 850 temperatures pushing 15c in the south. Should be enough
to push temperatures into the 70s everywhere...with inland areas in SW ME
and southern New Hampshire making a run at 80.

Forecast confidence begins to wane after Sunday...as the GFS
pushes a cold front fairly quickly Sun night and Monday...while the
00z Euro holds it up over the area as a positive tilted 500mb trough to
the west needs to wait for a kicker...and this would keep the chance
of rain showers in the region right through Tuesday.

&&

Aviation /13z Wednesday through Sunday/...
short term...IFR/LIFR ceilings/visibility in morning fog...becoming VFR.
Areas of IFR/LIFR in patchy fog tonight. VFR Thursday.

Long term...mainly VFR Thursday night through Sunday...with some valley
fog possible Friday and Sat night. Some rain showers at khie/kleb possible
Sat night into Sunday could also produce MVFR at times.

&&

Marine...
short term...no flags.

Long term...brief burst of northwest winds behind a cold front could
approach Small Craft Advisory criteria late Thursday night into early Friday. SW flow picks
up Saturday and may need Small Craft Advisory late Saturday into Sunday due to
winds and seas.

&&

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

&&

$$
Jc

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