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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 201449
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1049 AM EDT Sat Apr 20 2024

.SYNOPSIS...
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A cold front approaches the coast late this morning bringing
showers to the area with more persistent showers along the
coastal plain until mid day. A secondary front crosses this
evening with scattered showers, isolated thunder, and blustery
winds. Mostly dry conditions are expected Sunday. Another cold
front crosses Sunday night with dry and gusty conditions on
Monday. The next system to bring widespread precipitation to the
region arrives around Wednesday.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

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10:45am Update... Focused on POPs with this update. The steady
period of light pushes offshore through early this afternoon,
and then some pop up showers and a few thunderstorms develop
late this afternoon as a shortwave pivots through Quebec. Added
isolated thunder for this afternoon, as well as the chance for
some small hail with cold temps aloft. The best chance these
looks to be outside of southern New Hampshire. Not expecting
anything more than graupel and pea sized hail, so much more a
novelty than a concern. Rain also likely ends as a few snow
showers across the higher terrain as colder air pours in behind
the front this evening.

645 AM Update...Have mainly refreshed PoPs to align with
observed trends which has not resulted in any significant
changes. A narrow band of moderate rain has developed from
central Mass through the coastal plain of NH and Maine with
lighter showers to the NW through the mountains. This narrow
band of moderate rain will persist along the coast through the
morning with drier air working into NW zones as winds have
already shifted out of the west across northern VT.

Previously...

Rain showers are starting to overspread the area early this
morning as a cold front drops southeast through the area. This
front will stall along the coast through the morning leading to
the coastal plain seeing a soaking rain through mid day while
drier air works into from the NW. This dry air will lead to
thinning cloud cover and a few hours of precipitation free
conditions, first over NW portions of the area and then towards
coast early this afternoon.

A vort max rotating around an upper low over eastern Canada will
approach the area from the west later this afternoon. This will
lead to additional showers developing this afternoon into this
evening. These showers may be able to tap into some instability
and with freezing levels dropping to 3KFT north to 4KFT south
they could produce some graupel along with some snow showers
into the higher terrain. Additionally, behind this mornings
rainfall, the boundary layer will deepen along with low level
lapse rates steepening. This mixed boundary layer with inverted
V soundings will also bring the potential for gusty winds with
these afternoon showers as some runs of the HRRR suggest gusts
could reach 40 mph. This gusty showers activity will wane with
the loss of heating this evening. Highs today will range from
near 50 degrees across the north to near 60 degrees across
southern NH and interior SW Maine.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
Skies will turn mostly clear tonight while winds remain breezy
out of the NW. These winds will limit radiational cooling while
a cooler and drier airmass moving in will allow for lows in the
low to mid 30s with cooler readings across the north.

Broad cyclonic flow will continue over the Northeast through
Sunday. A dry airmass in place should lead to a mostly dry day
across the area while daytime heating will lead to clouds
bubbling up by Sunday afternoon. Highs will range from the mid
40s north to upper 50s south.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Overview...

A broad trough extending into the Northeast brings seasonably
cool and dry conditions into midweek on northwesterly flow.
Conditions likely become unsettled again by Wednesday into
Thursday as a slow moving front progresses through New England.

Details...

A weak area of low pressure passes to the north Sunday night
and Monday, bringing the chance for some showers to northern
areas and the higher terrain Sunday night and Monday. South of
the mountains, conditions look to remain dry. A weak and dry
front passes through the area Sunday night, bringing dry
conditions and breezy northwesterly winds, along with cool
temperatures. South of the mountains, fire weather is likely to
be a concern, while temps in the 30s and 40s through the
mountains and foothills lessens these concerns.

Temperatures and humidity begin to rebound by Tuesday as
southerly flow returns ahead of an approaching cold front. High
pressure will crest the region early in the day Tuesday and
strengthen as it moves out south of the Canadian Maritimes.

A slow moving front pushes into New England on Wednesday and
into Wednesday night, with an area of low pressure likely to
develop. How organized and significant this system becomes
remains the subject of some uncertainty, but regardless showers
at least look likely across the forecast area. With high
pressure centered to the north across Quebec, some precip is
likely to switch to snow by Wednesday night, particularly across
northwestern locations and the higher terrain.

The Thursday-Friday time remains uncertain at this point as the
low pressure system will be slow to depart to the east, but
strong high pressure will push in from the west. There is likely
to be a sharp gradient from clear skies and warmer temps to the
west, with cool and damp conditions to the east. Whether this
occurs at night or during the daytime on Thursday remains
uncertain, but will result in two very different outcomes
depending on the placement of these features. We`ll have to wait
at least a few more days before the details become more clear
on this.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
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Short Term...MVFR to IFR conditions are expected at KMHT and
KCON through late morning before improving to VFR this
afternoon. MVFR to IFR conditions are expected at KPSM, KPWM,
KAUG, and KRKD through mid day with improving conditions this
afternoon except at KRKD which may hold onto low cigs through
the afternoon. Upslope clouds and showers with bring periods of
MVFR through today at KHIE while KLEB remains predominantly VFR.
Steady west winds tonight will allow for mainly VFR tonight
with VFR likely on Sunday.

Long Term...Mainly VFR conditions are expected at most
terminals from Sunday night through Tuesday, except at HIE
where a period of MVFR ceilings is likely late Sunday and Sunday
night. Restrictions are likely on Wednesday as showers and
lower ceilings return, with MVFR to IFR conditions likely.
Improvement is likely on Thursday, but a return to VFR may take
until Thursday night.
-- End Changed Discussion --

&&

.MARINE...
Short Term...Steady southwest to south flow prevails today as
front slowly crosses the waters bringing periods of rain. The
front shifts east of the waters this afternoon with a second
round of gusty showers approaching the waters from the west that
could bring isolated gusts up to 30 kts through this evening.
Winds turn westerly tonight before shifting out of the southwest
Sunday. Winds could approach 25 kts Sunday afternoon while seas
remain below 5 feet during the period.

Long Term...A weak front crosses the waters Sunday night, with
high pressure building in behind the front for Monday and
Tuesday. SCA conditions are possible in northwesterly flow on
Monday. The high moves east of the waters by Tuesday as a cold
front approaches from the west, with SCA conditions possible in
southwesterly flow Tuesday and Wednesday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$


NEAR TERM...Clair
SHORT TERM...Schroeter
LONG TERM...Clair