Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 280158

Area Forecast Discussion
National Weather Service Gray ME
958 PM EDT SAT AUG 27 2016

High pressure over the area tonight will move east into the
Atlantic on Sunday and create a cool onshore breeze over coastal
areas. A cold front arriving from the west will bring a chance of
showers and thunderstorms Sunday into Sunday night with high
pressure building in behind the front through midweek. Another
cold front will cross the area Wednesday. Cool high pressure will
follow the front for later in the week.


10 pm update: Skies continue mostly clear. Input latest obs data.
No changes needed at this time.

720 pm update: skies mostly clear across the region with any
remaining clouds fair weather clouds dissipating around sunset.
After input of latest obs data only very minor tweaks to
temperatures needed. Rest of forecast looks good for the overnight

Previous Discussion:
High pressure continues to rotate offshore tonight. Before north
flow is established winds will become light and variable. Clouds
this afternoon will dissipate with the loss of daytime heating but
there will be some increase in mid and high clouds from the west
towards morning as a warm front lifts north. Light winds combined
with a dry airmass should provide ideal conditions for radiational
cooling overnight...with temperatures dropping into the 50s in
most locations.


As the low pressure system moves through southern Quebec, onshore
flow will become established making for a sticky, humid time on
Sunday. Increased cloud cover and humidity will keep temperatures
lower in Maine than they are today. Places like Keene...
Manchester...and Nashua will peak in the mid 80s however. Gusty
winds develop Sunday afternoon ahead of an approaching cold front.
Offshore stratus and fog will form and approach from the SE,
possibly bringing some drizzle to coastal areas towards nightfall.

A cold front will slowly drop into the region Sunday night into
Monday morning. The best forcing does not arrive until after 2 am
when a sharpening upper level trough and right entrance region of
a jet stream impinge on NH and ME. There is enough elevated
instability for at least isolated thunderstorms, but enough
forcing will need to be realized to erase the cap for any thunder
to develop. Some areas will see very little rain while other
areas, such as the mountains, will receive more. Heavy downpours
will be possible with such high moisture in place and flow
aligning throughout the atmospheric column.


The cold front will continue to move out to sea Monday morning as
drier air starts to move in from the west on gusty northwest
winds. Will keep the slight chance of a shower in the forecast for
the mountains during the day as a weak trough passes to the north
and colder air moves in aloft. Temperatures Monday should continue
to be warm in southern areas though...reaching the mid to upper

High pressure then settles over the area for Tuesday with mostly
sunny skies and temps across the region mainly in the 70s to lower
80s. Another cold front will cross the area Wednesday. This will
bring another chance for showers and possibly a
thunderstorm...depending on timing. A cooler area of high pressure
will drop down from Canada behind the front for Thursday and
Friday. An upper trough could bring a shower to mountain areas
Friday as it swings through.


Short Term...VFR conditions will prevail through Sunday afternoon
although LIFR fog is likely once again in HIE and LEB.

Long Term...
Any MVFR conditions Monday morning should improve to VFR during
the day. MVFR conditions are also possible Wednesday in any
showers or possible thunderstorms with the frontal passage.
Otherwise...mainly VFR conditions expected through the period.


Short Term...High pressure shifts into the Gulf of Maine tonight.
Fog and stratus may develop over the ocean, pushing toward the
mid coast Sunday morning. Late Sunday night into Monday morning
fog and stratus are likely

Long Term...
SCAs may be needed Monday as northwest winds cause seas to
build to near 5 feet offshore.




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