971
FXUS61 KGYX 050246
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1046 PM EDT Fri Apr 4 2025

.SYNOPSIS...
The next low pressure area will be approaching Saturday.
Precipitation overspreads the area during the second half of the
day. Some snow is possible, but most likely it will be a wintry
mix followed by a transition to rain. The weather pattern will
remain active into next week with additional chances for wintry
weather.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
1045 PM Update... A few locations have managed to decouple
enough to allow for some radiational cooling this evening with a
few spots already down to near or a bit below freezing. This is
a little colder than the previous forecast and therefore lowered
low temperatures in these locations. Elsewhere, the forecast
remains largely unchanged as cirrus continues to gradually
spread over southern and central areas.

Previously...
715 PM Update... Minor changes to reflect latest observational
trends. Middle to high level clouds will be on the increase this
evening but otherwise it will remain dry with temperatures
quickly cooling from earlier highs.

Previously...
Mostly clear skies start the night with high cirrus
overspreading late. Increasing overcast plus residual breeze
will keep temps from falling off due to radiational cooling. The
light north winds will slowly turn NE and then E by Saturday
morning as high pressure drifts over the Canadian Maritimes.
Even with onshore flow off the Gulf of Maine, the net origin is
continental given the short fetch. This will play a role in when
precipitation begins Saturday.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Much of Saturday morning remains dry for the area with
precipitation nearing the NH/VT border towards noontime. Other
than pushing precip onset back a few hours, much remains the
same for the mixed precip event Saturday into early Sunday
morning.

Analyzing hires guidance, best precip rates may accompany
initial band of frontogenesis that spreads through the forecast
area through the afternoon and early evening. Rates and
wet bulbing should allow at least a quick burst of sleet/snow
at onset before trending towards rain outside of the mountains.
This initial window may prove slick with some light snow and
sleet accumulations.

To the north, issued a Winter Weather Advisory mainly due to
freezing rain. Ice accretion will be on the light side below
2000ft due to moderate temperatures around 30 for much of the
event. That said, elevated and untreated surfaces still become
slick, especially as the sun sets into the evening. Warm air
advection eventually invades north of the mountains, allowing
most areas to switch to rain around daybreak Sunday. Started the
Adv in areas most confident in ice accretion, but higher
elevations outside of the Adv area will still see accumulation,
mainly in northern Grafton Co, NH.

Complicating factor in the higher terrain will be strong SE
winds over the ridges. Gusts may reach 40mph at times Sat
afternoon and evening. Should ice accumulate, this could cause
some tree damage.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
03Z Long Term Update... Latest forecast guidance continues to be
about evenly split on whether or not the trailing front on
Sunday night into early Monday will allow for a period of light
snowfall. Therefore did not change the latest NBM PoPs given
this uncertainty, with the highest PoPs over southern locations.
This will then quickly be followed by another system Monday
night into Tuesday that has a higher potential to bring some
snow to the area. Cooler than avg temperatures then look to
prevail through the middle of next week.

Previously...
The 500 MB pattern across NOAM still favors troughing over E
Canada and the US eastern seaboard into next week, but the
downstream blocking has been changeable, so we don`t completely
settle into troughing for an extended, but it is more present
than not. However toward the end of the week there are signs
that maybe that equivocal block does shift off the N Atlantic
with low pressure moving into Greenland. It looks changeable
through the forecast period with some dry days and some wet
ones.

Sunday will start off cloudy and may see some morning showers,
especially over coastal and far E zones, as the occlusion lifts
to N and the cold front moves in from the NW. Inland areas
should begin to see some sun in the afternoon, not sure if that
will be true for the coast and S NH. The cold front doesnt
really cross the CWA until midday through the afternoon, so,
highs will range from the mid 40s in the mtns to the mid 50s in
the S.

Sunday night and Monday remain uncertain as the 12Z Euro has
become more progressive with the front moving offshore, and
keeping precip out of the CWA, for the most part, while the GFS
deepens the 500 MB trough to our W, without phasing it with deep
convection from S stream wave in the S. The GFS 12Z ensemble,
is much less bullish with this feature, and this may the product
of convective scaling problems. Going to lean more heavily
toward the Euro, and just go with chance pops over the srn zones
late Sunday night into Monday. There will still be a lot of
clouds around Sunday night and Monday, especially in the S, but
could be more partly sunny in the N on Monday. Lows range from
the upper 20s in the mtns to the the mid 30s in the S.

The models are in a little better agreement for the system
moving through Monday night, which keep the N 500 MB trough on
its own with weak low pressure crossing N NH and ME, and no
coastal development. This should bring some precip into region
for the second half of Mon night through about midday Tuesday.
Should be mainly rain on the coast, but may see a few inches of
snow in the mtns. Highs will be in the mid to upper 30s in the
mtns to the mid 40s in the S. Wed looks dry and colder, with a
warming trend on Thu.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Short Term...VFR tonight. LLJ passes this evening with light
winds at the surface. This could result in LLWS, but with not
much directional shift. Clouds thicken and lower tonight through
Saturday morning. Precipitation, mixed, overspreads terminals
from west to east during the afternoon. This will include a
burst of SN/PL initially, then change to RA. In the mountains,
HIE and other northern terminals will see frozen precip hang on
longer, as well as FZRA through Saturday night.

Long Term...Sunday could start off with a few hours of MVFR or
IFR, but should see improvement to VFR during the afternoon. The
coast could return to MVFR later Sunday night into Monday
morning. If theres any break on flight restrictions Monday,
they will return on Tuesday in some light rain or snow.

&&

.MARINE...
Short Term...Below SCA through Saturday morning. Winds and seas
approach SCA thresholds Saturday evening and overnight as low
pressure nears the waters from the west. Expect winds to become
onshore Sat morning, becoming SW early Sunday morning.


Long Term...Seas/winds generally stay below SCA
levels Sunday through Wednesday, with weak low pressure passing
to our S on Monday, and to the N on Tuesday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory from 1 PM Saturday to 8 AM EDT Sunday
     for MEZ007>009.
NH...Winter Weather Advisory from 1 PM Saturday to 8 AM EDT Sunday
     for NHZ001-002.
MARINE...None.

&&

$$

NEAR TERM...Tubbs
SHORT TERM...Cornwell
LONG TERM...Cempa/Tubbs