Area Forecast Discussion
Issued by NWS Portland, ME-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KGYX 261114
Area Forecast Discussion
National Weather Service Gray ME
714 AM EDT Wed Oct 26 2016
A trough of low pressure will linger over the area today. A narrow
ridge of high pressure will build in from the west overnight and
will slide off to the east on Thursday. Low pressure will approach
from the west Thursday afternoon and will slowly move east through
the region Thursday night and Friday. A ridge of high pressure
will build in from the west Friday night and will be quickly
followed by a cold front on Saturday. High pressure will build in
from the west saturday night through Monday.
Quick update to adjust temp/td/sky grids. Skies are fairly clear
downwind of the mountains early this morning but expect clouds to
fill in as heating gets going later this morning. Aside from a few
stray sprinkles or flurries in the mountains...should see a dry
day. No other changes planned attm.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
One more day of cyclonic flow over the region as upper low
gradually releases its grip on the area. Should see a day much
like Tuesday with cloudy skies in the mountains with scattered
rain and snow showers. Remainder of the forecast area will see a
mix of sun and clouds along with much less wind. Highs will range
from the mid to upper 30s north and will range through the 40s
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Narrow surface ridge will build in from the west overnight. Should
see diminishing clouds during the evening downwind of the
mountains and skies clearing in the north after midnight. Expect
radiational cooling with lows ranging through the 20s in most
High pressure will quickly slide off to the east on Thursday as
low pressure approaches from the west. High clouds will be edging
into southwest zones by around daybreak and will quickly
overspread the forecast area in the afternoon. Expect rain to push
into southwest New Hampshire by mid afternoon and may see a brief
period of sleet and and wet snow at the onset...especially over
the higher terrain. Highs will top out in the lower to mid 40s.
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Upcoming hazard potential: Accumulating snows north Thursday night
into Friday, in particular the higher terrain.
Upper level low quickly deepens and becomes negatively tilted as
it progresses eastward Thursday night. Main surface low will be
situated over northern New York State Thursday night as
cyclongenesis takes place in area of strong diffluence aloft and
strong low level warm air advection along the Southern New England
This favorable track for enhanced precipitation will move the
surface low from the Mass-New Hampshire border and into the Gulf
of Maine by Friday. Boundary layer temperatures will be warm,
however thermal profiles suggest temperatures may be cold enough
for accumulating snow over northern areas. Far northern areas may
reach the snow advisory range and we are well coordinated with WPC
and CAR at this time. There may be some enhanced snowfall across
the highest peaks. In particular, the Mount Washington area and
the Presidentials will need to be monitored for potential enhanced
accumulating snows above 5000 feet.
System slowly departs Friday night with another trough approaching
from the west Saturday. This will mainly be an all rain event.
High pressure will then build over the region from Canada late
this weekend and early next week, however this surface ridge will
not tap overly cold air.
.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
Short Term...areas of MVFR ceilings in the mountains this
morning...otherwise VFR. VFR tonight through Thursday morning.
MVFR/IFR ceilings developing Thursday afternoon.
Long Term...Mainly IFR conditions Thursday night into Friday with
locally LIFR conditions. There could be a period of LLWS. Conditions
Short Term...Dropping SCA`s with the morning package.
Long Term...Will be issuing a Gale Watch for the outer waters
this forecast package for late Thursday night into Friday morning.
Sufficient southeasterly gradient ahead of approaching low to
briefly put the outer waters into a Gale, followed by backing
winds Friday morning.
MARINE...Gale Watch from late Thursday night through Friday morning for