Area Forecast Discussion
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FXUS61 KGYX 250036
Area Forecast Discussion...CORRECTED
National Weather Service Gray ME
836 PM EDT Fri Mar 24 2017
A cold front will drop south through the region tonight and will
stall southwest of the area on Saturday as high pressure builds
in from the north. High pressure will crest over the area
Saturday night and will shift east on Sunday. Low pressure will
slowly approach from the midwest Sunday night through Tuesday
and will pass out to sea south of the region Tuesday night and
Wednesday. High pressure will build in from the west Wednesday
night through Thursday.
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Update...Changes to the PoP grids based on latest radar trends.
Much of Srn NH has seen steady precip lift N...but I expect some
showery precip to drift back S later tonight as the front drops
back in that direction. It also appears as if the warmth aloft
is stalling on a NW to SE line just NE of HIE to IZG to PWM
line. It will begin to work back S across NH...while over Wrn ME
it should edge Nwd some more into the Capital Region. Some light
mixed precip is possible for that area...but precip intensity is
also dropping with time. I will also drop the winter wx advisory
for much of central NH and extend thru 06z for Coos County where
snow should remain steadier.
Previous discussion...Broad area of over-running draped across
the region will persist through this evening producing snow in
northern zones and gradually going over to rain in southern
zones. Getting quite a bit more QPF out of this system than
models had depicted with snow accumulations approaching
advisory levels in portions of Central and northern New
Hampshire. Have issued winter weather advisories for central
and northern New hampshire through this evening for additional
accumulations of 1 to 3 inches.
Farther south and in southwestern Maine snow will gradually mix
with and change over to sleet and rain as boundary layer warms.
Snow accumulations in these areas will generally be in the 1 to
3 inches range before changing over. Cold front dropping south
will change liquid precip back to snow and sleet later this
evening and overnight. Lows overnight will range through the 20s
north and lower to mid 30s south.
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
High pressure will gradually build south from Canada behind the
front on Saturday. Morning clouds and snow showers in southern
zones will be gradually suppressed to the south during the day.
Highs will top out in the lower to mid 40s across the region.
High pressure will crest over the region Saturday night
producing mostly clear skies and light winds. Should see good
radiational cooling with lows ranging through the single numbers
north and teens to mid 20s south.
.LONG TERM /SUNDAY THROUGH FRIDAY/...
Very complex pattern and active pattern to continue through
next week with bouts of mixed precipitation.
High pressure will remain locked over New England on Sunday,
suppressing precipitation to our south for a short period of
drying out. However, moisture returns northward with a returning
warm front Sunday night into Monday. This will be during a
period of cold and relatively dry air locked in near the
surface. The threat of sleet and/or freezing rain will continue
during this period, especially during the Sunday night into
early Monday timeframe as a weak wave crosses through the Gulf
of Maine. Have highlighted this possibility in the briefing
Models are having a challenging time picking up on individual
short waves crossing through the Gulf of Maine thereafter. One
short wave exits through the Gulf on Tuesday, with the GFS
solution holding back more energy for Tuesday night.
On Wednesday, somewhat drier air finally filters into the region
behind exiting low pressure into the Canadian maritimes. Cooler
air filters into the region on Thursday due to high pressure
building southeast. However, this batch of cold air will not be
as cold as previous shots of cold air advection as yet another
system approaches from the south. By Friday significant
precipitation may very well be entering the forecast area.
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Short Term...MVFR/IFR ceilings and vsby tonight....improving to
VFR on Saturday. VFR Saturday night and Sunday.
Long Term...Areas of IFR and patchy LIFR developing Sunday. This
will continue right through Tuesday night. Improving conditions
with high pressure on Wednesday.
Short Term...Continuing SCA`s for the bays and outer waters
Long Term...SCA conditions possible Sunday night into Monday as
low pressure approaches the region. Gusty northwest winds will
occur on Thursday behind an intensifying low pressure system.
NH...Winter Weather Advisory until 2 AM EDT tonight for
MARINE...Small Craft Advisory until midnight EDT tonight for