Area Forecast Discussion
Issued by NWS Portland, ME
FXUS61 KGYX 311434
Area Forecast Discussion
National Weather Service Gray ME
1034 AM EDT TUE MAY 31 2016
A cold front will move into the region today. High pressure will
build in from the northeast tonight through at least Thursday night
with cooler temperatures but fair weather. A front moves through the
area on Friday with a chance of showers. More showers are expected
Saturday as an upper level system moves through. High pressure
builds in on Sunday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1030 am update...little change to the going forecast. Have
adjusted temperatures up a little bit based on latest
observational trends. Otherwise, a few showers and perhaps an
isolated thunderstorm possible later this afternoon across the
western ME mountains with approaching cold front.
6am... clouds are hanging along the coast. HIE and 1P1 have fog
which should dissipate soon.
A region of high clouds associated with the front is draped along
the Maine coastline. Rain remains well out to sea in the Gulf of
Maine however southwesterly flow over the water is generating fog
from Penobscot bay southwards to Sagadahoc county. The back edge
of the clouds is moving out of New Hampshire. As skies clear
sunrise fog may form in the valleys.... especially the Connecticut
river valley where trapped moisture is plentiful. Any fog will
burn off a few hours after sunrise making way for a mostly sunny
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
A secondary cold front will move southwards out of Canada bringing
drier and cooler air under northwesterly flow. While forcing remains
weak the upper level short wave may be just enough to touch off some
isolated thunderstorms this afternoon along the Canadian border.
Wednesday high pressure will build into the forecast area. Weak
pressure gradient will allow a sea breeze to move well inland in
the afternoon. This will help to keep high temperatures in the 70s
under sunny skies.
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
High pressure shifts offshore Thursday allowing onshore flow
to become established. This will set the stage for cloudier skies
and cooler temperatures than previous days. Some drizzle and fog
is possible especially along the coast. A cold front approaches
from the NW by Friday morning further increasing moisture
transport into the region. The front stalls initially as it waits
for a short wave kicker to round the base of a digging upper
Showers will spread across the entire area Friday with the front
and Saturday as the upper level trough axis passes by. The
heavier showers will be confined to the higher terrain on Saturday
with the aid of orographic lift.
High pressure builds in briefly on Sunday but clouds will
remain with short wave energy associated with the northern
periphery of the upper level ridge. A warm front moves into the
area by Monday morning bringing a widespread soaking rain through
Tuesday morning. Vertically stacked upper low will rotate
overhead by Tuesday evening keeping showers in the forecast.
High temperatures during this time will be a couple degree
either side of normal and lows will be a few degrees higher than
average thanks to insulating cloud cover.
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
Short Term...VFR through Wednesday.
Long Term...VFR conditions for most of Thursday with the
possibility of fog and drizzle in the early morning hours and
again at night. Drizzle would be confined closer to the coast
however fog will likely form in mountain valleys as well. There
will be a chance of showers on Friday and the low level
southeasterly flow could transport some low clouds off the Gulf of
Maine and into eastern New Hampshire and western Maine at some
point with IFR conditions possible. Conditions improve to VFR
again behind a cold front on Saturday.
Areas of fog over the waters as an airmass with dewpoints in the
60s continues to move over the cold water. A front will cross the
region moving in drier air. winds will pick to to 10-15 kts
tomorrow from the northwest behind the front.
Long Term...Winds and seas will be on the light side with a weak
frontal passage Saturday. A stronger warm front will lift across
the waters Monday and this may create stronger winds and higher
Drier air will move in today dropping RH to around 30% over southern
New Hampshire and southwest Maine. Northwesterly winds up to 15-20
MPH will also aid in drying out fuels. Recent greening up should
preclude the need for fire weather watches/warnings.
NEAR TERM UPDATE...Ekster