Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 240627

Area Forecast Discussion
National Weather Service Gray ME
227 AM EDT Thu Aug 24 2017

An upper trough over the northeast, and a series of weak
surface troughs, will provide cool weather to the region through
Friday. High pressure will build slowly east from the midwest
this weekend through early next week.


The large upper low which has been affecting the region is now
positively tilted, with its center near Newfoundland and the
main trough axis extending WSW towards the western Great Lakes.
The northeast was sandwiched between moisture over the Great
Lakes and Canada and more moisture associated with a baroclinic
zone well off the New England coast. In between, dry air was
concentrated. Last nights GYX sounding was case in point and
surface dew points this morning were in the 40s and 50s.

The only clouds of note this morning are stratus affecting the
northern mountains of NH and western Maine trapped under an
inversion. Otherwise skies were clear and patchy fog should
form shortly in valleys and low lying areas.

Cyclonic flow aloft continues today with a weakly defined
surface trough passing through the region. Some additional
cloudiness will be the result...but temperatures should still be
on the warm side with upper 60s north to mid 70s to maybe even
80 degrees across the south.


Tonight, another weak surface trough passes through. This will
bring some stratus as well as fog and perhaps a brave shower
over the mountains. Lows will drop into the mid 40s north to mid
50s south with partial radiational cooling occurring.

The main trough axis of the upper low finally nears Friday night
and crosses the region bringing more cloud cover as well as
higher chances for some sprinkles over the north. Any
precipitation will be light. Temperatures Friday will be in the
mid 60s north to lower to mid 70s south, and will once again
feel fall-like with low relative humidities.


Upper trough and associated cold pool aloft will remain entrenched
over the northeast over the weekend. Expect diurnal clouds to
gradually diminish Friday evening downwind of the mountains.
Clouds with upper trough axis will perisit in the north before
diminishing after midnight. Lows Friday night will bottom out in
the mid 40s to lower 50s.

Both Saturday and Sunday will feature a mix of sun and clouds and
highs from the mid 60s to mid 70s as high pressure continues to
build over the northeast. Lows Saturday and Sunday nights will
again range from the mid 40s to mid 50s.

Fair weather will continue across New England Monday and Tuesday
as High pressure crests over the region before Shifting east.
Looking for mostly sunny skies both days with highs edging upward
With readings across the area topping out in the lower to mid 70s
by Tuesday.


Short term /through Thursday Night/...VFR for prevailing for
most terminals and times. The exceptions are HIE and LEB this
morning which may experience IFR valley stratus and fog between
09-12z Thu and again 08-12Z.

Long Term...Mainly VFR conditions with light winds through the
period. However, some of the deeper, inland valleys will have
patchy late night fog during the period, especially in the
Connecticut River Valley. Radiational cooling conditions
expected and fog will likely form despite limited moisture and
lowered dew point values.


Short Term /through Thursday Night/...Small craft conditions are
not expected tonight through Friday.

Long Term...Seas and winds will remain below SCA thresholds as a
large area of Canadian High Pressure builds slowly over the
waters with time.





LONG TERM...Sinsabaugh is the U.S. government's official web portal to all federal, state and local government web resources and services.