Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 240721

Area Forecast Discussion
National Weather Service Gray ME
321 AM EDT Mon Oct 24 2016

Low pressure meandering over the maritimes will keep a strong
west to northwest flow over the region today through Tuesday, with
upslope snow accumulations expected in the mountains. High
pressure will build in from the northwest Wednesday and Wednesday
night. Low pressure will approach from the west on Thursday and
will cross the region Thursday night and Friday.


500 mb trough and associated sfc low are tracking across srn new
England this morning. With dry air in place, and best dynamics
moving south of the CWA, the precip will pass to our south. Cannot
rule out a sprinkle moving along the NH/MA border thru about 12Z,
but other than it will be dry. Will also see some clouds moving
through with the 500mb trough, but these should clear out by mid-
morning, too. Behind this wave winds will pick up again and
another shot of colder will filter in this afternoon. The winds
will not be as strong as Sunday but gusts of 25-30 mph will be
possible, especially this afternoon. Upslope should get going
again this afternoon in the mountains, but best chance for accums
will be overnight. highs today will range from around 40 in the
mountains, to around 50 on the coast and in southern NH.


NW flow continues tonight and another wave will move through the
500mb trough, so any clearing in the south will become partly to
mostly cloudy by evening. This should also help enhance the
upslope flow overnight and could see an inch or two of accums up
to 2500 feet, and 2-4 inches above that. Winds will diminish, but
should keep going at around 10-15 mph in many spots, which will
deter rad cooling in all but the most sheltered areas. Overnight
lows will range from around 30 in the north to the mid 30s in the

Tuesday will get breezy again, although a little less so than
Monday. While upslope SHSN will diminish somewhat in coverage and
intensity, they will continue thru the day, with some accums still
possible in the higher terrain. Some sun can be expected in the
downslope on the coastal plain with highs a couple degrees cooler
than Monday, mostly on the coastal plain, and temps will range
from round to near 50.


Cyclonic flow will continue over the region Tuesday night and
Wednesday as upper low slowly pulls off to the east. Looking
for mostly cloudy skies Tuesday night with lows in the mid
20s to mid 30s. Clouds will hang tough in the mountains on
Wednesday with downsloping winds producing a mix of sun and
clouds to the south. Highs on Wednesday will range from the
upper 30s to upper 40s.

High pressure building by to the north will bring diminishing
clouds Wednesday evening as upper low pulls away to the east.
Good radiational cooling will allow temps to bottom out in the
upper teens to mid 20s north and upper 20s to near 30 south.

Shortwave approaching from the west on Thursday will bring the
potential for a messy mix of wet snow...sleet and rain over
higher terrain in interior sections of the forecast area
as cold air dams up east of the mountains. Still some timing
diffs between ECMWF and GFS but precip looking more likely to
begin Thursday afternoon in southern New Hampshire and will spread
northeast Thursday evening.

Depending on the track of the surface low expect warmer air to
gradually erode cold air over the region Thursday night as strong
onshore flow sets up ahead of approaching low. Expect mixed precip
in inland areas to gradually change to rain overnight.

Rain will continue on Friday as low pressure crosses the region
and will be tapering off in the afternoon as low pressure heads
into the maritimes. Axis of heaviest precip will likely set up
along the front range of the Whites in good upslope flow with
models showing 1 to 2 inches in these areas. Models also
indicating a fair amount of shadowing northwest of the

Friday night will bring a break in the action as low pressure
pulls away to the east. Models diverging quite a bit for the
weekend so forecast confidence rather low for Saturday and
Sunday. Will likely stay close to super blend pops for days
6 and 7.


Short Term...VFR expected at all terminals into Tue. W-NW will
gust from 20-25 kts today, especially in the afternoon. KHIE could
see MVFR to IFR flight restrictions tonight, mainly in SHSN.

Long Term...VFR Tuesday night and Wednesday with areas of MVFR
ceilings in the mountains. VFR Wednesday night. MVFR /IFR Ceilings
developing Thursday Afternoon. IFR/LIFR ceilings/vsby Thursday
night and Friday.


Short Term...HAve dropped the gales for SCA outside of the bays,
as W-NW winds will pick up a bit today and persist into Tue
morning, at least.

Long Term...SCA`s likely Tuesday night and Thursday Night.


MARINE...Small Craft Advisory until 8 AM EDT Tuesday for ANZ150-152-154.


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