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Area forecast discussion 
National Weather Service Gray ME
353 PM EDT Sat Jul 23 2016

a cold front will will push offshore tonight with scattered
thunderstorms ahead of the front. High pressure will build in
from the west on Sunday and will shift offshore Sunday night. A
cold front will approach from the west on Monday and will cross
the region Monday night. High pressure will build in from the west
on Tuesday and will crest over the area on Wednesday. A weak cold
front will slowly push southeast into the region Wednesday night
and will stall over the region on Thursday. High pressure will
build in from the north Thursday night and Friday.


Near term /until 6 PM this evening/...
scattered thunderstorms across the region at 3pm present the most
immediate threat. There are three distinct areas within the County Warning Area.
In the far north and eastern areas /Franklin to Kennebec to
Lincoln counties and northeast/ much of the instability has
already been rained out with earlier showers which will limit the
convective potential. In this area scattered showers and isolated
thunder are the threat. Further south and west... current shower
activity is focused along a line extending from hie to izg to pwm.
This represents the edge of the morning cloud field as well as
last nights convection. These boundaries will continue to help
enhance convection over the next few hours. The seabreeze is also
in play with convection firing already over the seabreeze front
at Kennebunk and Freeport. Finally to the southwest of this
area... in Hillsborough and Cheshire County New Hampshire dry air has mixed
down lowering the dewpoints. This puts southwest New Hampshire at a much
lower risk for thunderstorm initiation. The one threat for this
area would be from the convection currently moving out of Quebec
into northern Vermont. If this system is able to grow upscale into
an mesoscale convective system with a cold pool it will likely propagate into southwest New Hampshire
in the evening hours. In this case the dry low levels would
actually help to enhance the wind gust threat for this region.


Short term /6 PM this evening through 6 PM Sunday/...
showers will die off for most of the County Warning Area after sunset... with
southwest regions being the last to see showers end. As they do
skies will clear allowing patchy valley fog to form.

Sunday a weak ridge of high pressure builds in behind the front.
While temps aloft have decreased surface temperatures will remain
warm with highs in the 80s. Dewpoints will decrease behind the
front. With the weakening pressure gradient a sea breeze should
develop keeping the immediate coasting line in the 70s.


Long term /Sunday night through Saturday/...
a progressive pattern will develop for next week as the jet
stream moves a series of waves through southern Canada.Monday the
next short wave comes in dropping a front through the region. The
front once again looks to coincide with peak heating which will
allow for the potential for severe storms. Very warm and humid
airmass will be in place ahead of this system with daytime highs
ranging through the 80s north and upper 80s to mid 90s south.

After the front moves through Monday night a period of high
pressure builds in for Tuesday and Wednesday. Mostly sunny skies
will prevail with a nice seabreeze again forming for the coast.

As we move towards the end of the week forecast confidence
decreases markedly. Previous deterministic models had hinted at a
large wet system moving in for Thursday and Friday, however
current guidance is all over the map with a low center ranging
from the Great Lakes to off the coast. While wet seems to be the
trend, the details are too uncertain yet to put much weight in any
of the heavier rainfall scenarios and have gone with just a 50
pop. Beyond the wet end of the week guidance hints at a sunny
weekend... however put low confidence in all of this extended
forecast for the moment.


Aviation /20z Saturday through Thursday/...
short term...periods of thunderstorms and IFR through the next few
hours. Scattered 5000ft deck will decrease ceilings to MVFR at
times. After sunset look for VFR through the weekend except hie
and leb which may see some valley fog.

Long term...VFR Sunday night. VFR on Monday with areas of MVFR
ceilings and vsby in showers and thunderstorms. VFR Tuesday and


short term...a few scattered thunderstorms may reach the coastal
waters this evening otherwise seas below Small Craft Advisory.

Long problems noted.


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


near term...Curtis
short term...Curtis
long term...Curtis

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