Area Forecast Discussion
Issued by NWS Portland, ME
FXUS61 KGYX 252243
Area Forecast Discussion
National Weather Service Gray ME
643 PM EDT THU AUG 25 2016
A cold front will slowly cross the region late tonight and Friday.
High pressure will build in from the west on Saturday and will
shift east of the region on Sunday. A cold front will slowly push
east through the region on Monday. High pressure will build in
behind the front Monday night through Tuesday. A weak cold front
will cross the region during the mid week period.
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
640 pm Update: A few very light showers or spinkles passing mainly through
southern NH. Will extend the chc 20-30 pops further east across
southern NH for the next few hours but leave forecast for tonight
alone. Input latest mesonet data and suggested only minor
adjustement for temps for the early evening hours.
Weak cold front will approach from the northwest tonight bringing a
few showers and possibly a stray thunderstorm...mainly this evening.
Expect areas of fog after midnight. Low temperatures will range
through the 60s to near 70 degrees.
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Cold front will gradually drop south through the region on Friday.
Morning clouds will gradually give way to partly to mostly sunny
skies. Heating will generate some modest capes and a few showers
and thunderstorms will develop mainly in southern areas as the
front pushes through in the afternoon. Highs on friday will range
through the 80s to near 90.
Cooler and less humid air will filter into the region Friday night
as high pressure builds in from the west. Looking for mostly clear
skies and light winds overnight. Low temps will bottom out in the
lower to mid 50s north and upper 50s to mid 60s south.
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Over the weekend high pressure builds in from the north
allowing cooler and drier air to filter in. Bubble high pressure
develops over the Gulf of Maine bringing the seacoast of NH and
possibly southern portions of coastal Maine onshore flow
resulting in a partial sea breeze and slightly cooler
temperatures there. Overall temperatures will be several degrees
cooler across the south and inland areas.
Increasing moisture and warmth returns areawide Sunday evening
as high pressure shifts east. Expect to see another sea breeze
with this one penetrating farther inland. After a low of around
0.60", PW values increase once again to near 1.70" ahead of the
next short wave disturbance. Showers should develop Sunday
afternoon becoming widespread by Monday morning. The cold front
will move through NH and most of western Maine by early
afternoon. Bulk shear is not bad but there will little
instability so have only included thunderstorms ahead of and along
the boundary where forcing for ascent is best. Most locations
won`t receive much QPF if any... but with the high moisture in
the atmospheric column localized downpours are possible.
Another deeper short wave will affect the northeast around
midweek. Timing and other details are not in high confidence and
ensemble members are in poor agreement after Monday...so have
only included isolated showers at this time. Behind the FROPA it
does look windy for Wednesday night and Thursday as the pressure
gradient tightens between low pressure to the east and high
pressure to the west. Cooler air will arrive Thursday as a
Canadian airmass noses in from the north.
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
Short Term...Areas of ifr/lifr ceilings/vsby overnight. VFR Friday
night and Saturday.
Long Term...VFR conditions through the weekend. Lowering clouds
expected late Sunday night into Monday morning with MVFR or lower
conditions in showers and possibly thunderstorms. This will be a
greater threat for HIE AND LEB initially. Improving conditions on
Tuesday after some morning fogs.
Short Term...Continuing sca`s from this evening through 800 am.
Long Term...High pressure crosses the Gulf of Maine this weekend
with light winds expected. A cold front will arrive from the
northwest Monday morning, though winds with the front should
remain below advisory levels.
MARINE...Small Craft Advisory until 8 AM EDT Friday for ANZ150-152-154.