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000
FXUS61 KGYX 220702
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
302 AM EDT Wed Aug 22 2018

.SYNOPSIS...
An upper level trough will move east towards the region today,
bringing a chance of showers and thunderstorms as a cold front
moves through. This cold front will usher somewhat cooler and
drier air for late this week before a gradual warming trend
occurs over the upcoming weekend. A frontal system will bring a
chance for showers very late in the weekend and into early next
week.

&&

.NEAR TERM /THROUGH TODAY/...
Patchy fog and showers will continue to spread eastward across
the forecast area today as an upper level trough approaches the
region. A weak wave will likely form during the morning hours
over southern New England allowing for increased southerly flow
ahead of the system. This will advect moisture into the region
and allowing for a few briefly moderate to heavy showers in a
few locations.

Mesoscale models suggest this weak surface low will likely
follow a track over southeastern New Hampshire later this
morning and along the Maine coastline this afternoon before
perhaps moving inland in the Midcoast region. This track
minimizes significant destabilization across much of the
region. However, will still include a risk for a thunderstorm
over southern areas for the possibility of elevated convection.
Over far southern New Hampshire, dew points expected to climb to
near 70 degrees today and there is still a slight possibly gusty
winds as wind fields aloft will continue to be increasing.

Daytime maxes will be help down in the 60s over far northern and
eastern sections due to the onshore flow with 70s most
elsewhere. If southeast New Hampshire were to briefly break out
into some sunshine, the MHT to ROC corridor may nudge 80
degrees.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM THURSDAY/...
A cold front sweeps through the region this evening allowing for
drying and a weak west to northwesterly flow to set up. Gradient
however may be too weak to prevent fog from redeveloping in some
of the sheltered valley locations, especially in areas that
received heavy rainfall.

Full clearing may be slow to arrive with the upper low remaining
to our west. Expect overnight lows mainly in the 50s.

On Thursday, cold air advection will allow H8 temperatures to
drop into the +8C to +10C range. Downsloping will allow for the
warmest readings, mainly in the mid to upper 70s. It will feel
very comfortable with dew point values dropping into the 50s.

There may be a few clouds building during the midday hours with
the passage of the upper trough. This would mostly be confined
to the mountains.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
High impact weather: None

We`ll see a fairly quiet pattern evolve over the end of the
week and into the weekend. A long wave trough will shift east
out of the area on Thursday night allowing for high pressure to
build in for Friday into Saturday.

By Saturday night a short wave trough develops near the Great
Lakes, moving east into our area to bring rain Sunday night into
Monday. Here there is some variation within the models with the
GFS bring more progressive and the ECMWF lagging behind a bit
while the Canadian washes out the wave almost entirely. All of
this forward progression is dependent on the breakdown of the
block which has lingered over the Pacific for the past few days
and is currently just starting. Expect to see better agreement
tomorrow when more of the block has eroded, for now will stick
with a blend of models which leaves general showers in the area
for Sunday into Monday. In all cases the northward passing wave
will favor more rainfall in the mountains.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
Short Term...Areas if IFR conditions in showers, patchy fog and
isolated thunderstorms today. Some fog redeveloping in sheltered
valleys tonight before a drier, northwesterly flow kicks in.

Long Term...VFR conditions will prevail under high pressure to end the
week. Low pressure approaches from the Great Lakes on Sunday night
into Monday. Ahead of this increasing moisture may lead to sheltered
valley fog overnight. Showers will develop on Monday with scattered
MVFR ceilings possible.

&&

.MARINE...
Short Term...Winds and seas will approach SCA levels later today
as a southerly flow ahead of the front picks up, then switches
to NW behind the front tonight and becomes gusty for a few
hours.

Long Term...High pressure will build over the waters to start the
weekend. Sunday night southwesterly flow will develop ahead of
the next low pressure passing to our north. This will result in
gusts to SCA on the outer waters Sunday night into Monday.


&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$
Curtis/Cannon