Area Forecast Discussion
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FXUS61 KGYX 011409
Area Forecast Discussion
National Weather Service Gray ME
909 AM EST Thu Dec 1 2016
Low pressure will move out of the region this morning with rain
and snow coming to an end. Northwesterly flow will continue
through the start of the weekend with snow showers in the northern
mountains. Cold high pressure will settle in for the start of next
week before another storm moves in mid week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
905 AM...For this ESTF I adjusted near term grids to reflect
satellite and radar trends as well as the current mesonet. Winter
weather headlines have been dropped as well as the steadier
precipitation exits the area.
545 am...have dropped the southern part of the advisory, as
reports from this area say mainly heavy rain at this point, with
very little snow accumulations. Elevations above 2K ft may still
be snowing and could see addl accums, but these areas are limited.
Otherwise previous forecast unchanged other than T/Td/pops based
on current obs. WArning snow may be hard to reach in central
Somerset except over the higher terrain, but will hold for now, as
there`s still half an inch or so of QPF, even at lower ratios will
bring things close to warning, and snow will be wet and heavy.
Previously...Rain will end from SW-NE this morning across all but
the NE zones, where snow will mix with or change to rain during
the morning hours, at all but the higher elevations. Should see
enough for warning criteria in central Somerset, particular from
Jackman N. Still uncertain about surrounding zones particular S
FRanklin/Somerset, where some reports came in last night of mainly
rain. Temps from mesonet sites still hovering just above freezing
and radar Correlation coefficient shows melting band lifting NE
over the last couple of hours. Have trimmed back to advisory until
9 AM, and could even end it sooner once some reports come in.
Otherwise, look for some clearing this afternoon in southern NH and
SW ME with mild highs of 50-55 in these areas, otherwise mostly in
the 40s except far NE will be limited to mid-upper 30s.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
W-NW flow will diminish somewhat overnight, but should stay dry
and mainly clear outstay of the mountains. In the mountains will
see upslope SHSN, and maybe even SHRA at lower elevations in the
evening. Overall air mass is not that cold, but cyclonic flow
aloft will help keep the upslope going, although for the most part
it will stay light.
On Friday, some weak ridging aloft will keep the morning mainly
sunny on the coastal plain, and provide a bit of break of showers
in the mtns, but next approaching low will begin to head SE out of
the ST lawrence valley toward the crown of ME and clouds will be
on the increase across the CWA, with SHRASN increasing again in
the mountains and foothills.
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A long wave trough moves into the eastern portion of North
American for the start of the weekend. This will keep temperatures
cold with persistent northwesterly flow through the weekend.
Upslope snow showers will continue through the weekend... with
minor accumulation expected through Saturday in northern Coos and
northern Oxford counties.
Surface high pressure builds into the region on Monday as the
trough moves overhead dropping 850mb temperatures to -10C. Expect
mostly clear skies to allow for good radiational cooling and have
dropped temperatures slightly below most guidance to account for
this. Isolated mountain valleys may see temperatures near zero on
The trough aloft begins to progress eastward at the start of next
week. As it does the spread in timing of its departure results in
increasing uncertainty in the forecast. By midweek /anywhere from
Tuesday to Thursday/ the warmer air ties to push northward with an
accompanying surface low and precipitation. After a cold weekend
the tendency is for cold air to linger with the departing high
pressure creating cold air damming in through coastal Maine which
is being hinted at even in the global models at this far time
frame. Cold air at the surface and warmer air coming in aloft sets
us up for potentially messy mixed precipitation... however the
uncertain timing of the arrival and northward extend of the warm
air leaves ptype very much up for grabs. Due to the uncertainty
have kept rain or snow only for ptype at this point.
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
Short Term...MAinly IFR or lower through sunrise, with improvement
toVFR this afternoon. VFR will persist tonight and Friday, with
the exception KHIE which will be subject to upslope showers and
tempo flight restrictions tonight.
VFR conditions will prevail at all but HIE where upslope snow
showers will yield periods of MVFR through Saturday. Then VFR
returns through the start of next week.
Short Term...Gales and SCA will hold as they are, as strongest
E winds are beginning to take shape and will continue through
12-14Z or so before diminishing. Will see a brief break today as
low moves through and winds shift to W, but SCA will likely be
needed for at least the open waters tonight.
Northwesterly flow and cold advection will keep SCA for the outer
waters from Friday into Saturday.
MARINE...Small Craft Advisory until 11 AM EST this morning for ANZ153-
Gale Warning until 11 AM EST this morning for ANZ150>152.