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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KGYX 180807
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
407 AM EDT Thu Apr 18 2024

.SYNOPSIS...
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A weak disturbance brings a chance for light showers across New
Hampshire and far western Maine today into tonight. Temperatures
will trend cooler as an onshore component to surface flow
builds, culminating in the passage of a frontal system with
light rain late Friday into Saturday. Quiet, mild, and dry
weather, this time with more westerly flow, returns late
Saturday through early next week.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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Cirrus will be streaming over much of the area today, with some
cu developing across interior ME and NH today. Densest cloud
cover will be over parts of western and southern NH, where on
and off showers/sprinkles will be on the increase this afternoon
and evening.

Dry air has certainly been strong overnight into this morning,
with each band of incoming rain succumbing to it plus orographic
effects. Moisture advecting into upstate NY should eventually
build and overcome lower level dry air, resulting in light
showers later.

Temperatures on the day will warm the best where cirrus is thin,
and this looks to be up towards the Kennebec River Valley an
into interior ME with highs in the low to mid 50s. Depending how
quickly clouds thicken, could also see these warm temps up
towards the northern end of the CT River Valley.

Shower chances linger in NH and far western ME until this
evening. Decrease in coverage is expected thereafter, with a
fairly mild night in store.
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&&

.SHORT TERM /FRIDAY/...
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Onshore winds increase Friday with clouds sticking around.
Temperatures should be a bit more uniform compared to Thursday,
with highs generally in the mid to upper 50s. Cooler values are
possible along immediate coast (mid 40s to around 50) due to
advecting marine air. Profiles do bring to saturate towards late
afternoon ahead of a cold front. This brings the chance for
showers to the mountains initially, before overspreading
eastward into the evening and overnight hours. Trends continue
to show weak QPF out of this, and possible some areas only see a
trace of precip before midnight.
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&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
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An upper level ridge of high pressure off the Eastern Seaboard
is replaced by a broad upper level trough over the weekend.
While it will bring some unsettled weather, it is expected to
not be impactful with light precipitation amounts. If anything,
this change in synoptic setup results in a change of gradient
flow more favorable for westerly flow... and less favorable for
onshore flow, which should make for a pleasant stretch of Spring
weather.

A cold front brings light rain showers, generally less than a
quarter inch total across the region later in the day Friday
through Friday night with some question as to how quickly the
front will move out. Would expect the overnight to be fairly
humid with potential for low clouds and fog too, given more
onshore flow residency.

Saturday will see the cold front exit with stronger mixing, drier
air, and breezier winds up to around 25-30 mph out of the west. This
will allow warmer temperatures as well despite a little bit of a dip
in t850, with highs generally in the 50s across the north but into
the low/mid-60s south of the mountains. There is a chance the front
hangs up a bit near our area, which would prolong clouds and lead to
a little cooler temperatures.

A cooler airmass briefly settles across the international border
Sunday into Monday under a broad upper level trough with clearing
skies. Predominantly westerly flow continues in the meantime, which
will keep the maritime influence at bay for the most part and allow
for a warming (and drying) trend. Highs are forecast to be in the
50s and low-60s, with light flow and interior surface heating likely
allowing seabreezes to develop. By Tuesday, high pressure is more
likely to be located to our south... setting up a more southerly
flow, with further warming over the interior especially west but
allowing more maritime influence along the coast and into
interior southern Maine.
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&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
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Short Term...VFR today with diurnal winds. Some MVFR cigs
possible across western NH today, lingering overnight with
SHRA. Vis shouldn`t be impacted by these showers. Cigs improve
Friday morning, but could still have scattered MVFR for mainly
southern and western NH early. Winds will become more decidedly
SE this evening, becoming light overnight, and continuing
Friday.


Long Term...MVFR to IFR is more likely to develop Fri night
into Sat with -SHRA and lowered CIGs. VFR and W winds return
late Sat or Sun, lasting through the start of the coming week.
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&&

.MARINE...
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Short Term...Below SCA conditions. A few gusts around 20 kt will
be possible today and Friday. Onshore flow may result in
patches of fog or low clouds that impact visibility today and
Friday.

Long Term...SE flow continues Fri night, with an unlikely
chance of touching 25 kts while seas similarly increase to 2-4
ft. A cold front crosses Sat with winds turning W to SW AOB 20
kts thru Sun and into Mon with daily sea breezes possible. S to
SE flow develops by midweek.
-- End Changed Discussion --

&&

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

&&

$$


NEAR TERM...Cornwell
SHORT TERM...Cornwell
LONG TERM...Casey