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000
FXUS61 KGYX 141931
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
331 PM EDT Sun Apr 14 2024

.SYNOPSIS...
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Showers will gradually work in from west to east across the
region this afternoon although they may not get into ME until
this evening. This fast moving system will clear the area by
Monday morning. High pressure gradually builds in early next
week with partly to mostly sunny skies outside of the mountains
along with a warming trend. Temperatures will be slightly cooler
later in the week with a weak system potentially bringing a few
some showers to the area late Thursday into Thursday night. A
cold front approaches late in the week bringing another chance
for rain showers late Friday into Saturday.
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&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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Fast moving weak low pressure tracking ESE out of the lower
Great Lakes this afternoon, and bringing, what has so far
amounted to sprinkles to the CT valley and SW NH. Showers which
will measure some rain will move in later this afternoon as the
system overcomes some dry air a head of it and gets some extra
UVV from 850 mb jetlet as well as a brief spell of good upper
level jet dynamics. Still, should only amount to around of
showers that will likely last through the evening before
weakening and shifting east of the CWA. Should see some clearing
especially outside the mtns, which may allow temps to drop a few
degrees closer to the TD, and thus patch fog is possible late
and into early Monday. Lows range from the upper 30s in the mtns
to mid 40s in the S.
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&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
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Monday, for the most part, will be dry and should vary from
mostly to partly sunny. 500 MB trough axis crosses Monday
afternoon, and although fairly flat still could be enough to set
off some SCT showers, especially in NH and the mtns. They will
mostly be few and far between, but will show some signs o f
convection, given some weak instability from colder air aloft.
So, a brief heavy downpour may be possible, as will a small
threat for some graupel. But for the most part should be a
decent day with highs around 50 in the mtns to the upper 50s and
low 60s in the S. Mon night looks clear with light winds, so
some decoupling can be expected, but there enough boundary layer
flow for a pure rad cooling night. Also clouds may linger a bit
in the mtns. Therefore lows range from the mid 30s to around 40.
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&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
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Quiet weather is in store for Tuesday and Wednesday with broad
high pressure and a dry airmass over New England. The mountains
may see a few showers with upslope flow still in place on
Tuesday, and a weak reinforcing front could also result in a
couple of showers across eastern areas Tuesday night and early
Wednesday, but the vast majority of the area won`t see any
precip. And what does fall will be light. Temperatures are
expected to range from the upper 50s to mid 60s south of the
mountains on Tuesday, but not quite as warm for Wednesday,
especially at the coast with weaker flow allowing the seabreeze
to move inland.

For Wednesday night into early Friday, global models are in
general agreement showing an upper ridge building overhead,
which would prolong the stretch of mostly dry weather. However,
the GFS is still showing a dampening shortwave approaching New
England, temporarily weakening the ridge late Thursday into
Thursday night, which could bring some showers to the area. This
would be primarily in NH with amounts expected to be light,
while the ECMWF keeps the forcing and shower activity to the
north and west. Due to this uncertainty, have kept a chance
(30-40%) of showers in NH during this stretch with amounts
diminishing over into western ME.

The ridge then breaks down and shifts east Friday into Saturday
as low pressure center moves across eastward across James Bay
and into the Canadian Maritimes, sending a cold front toward New
England. This will bring the higher chance of rain Friday night
into Saturday, but as of the latest runs amounts look to be
light with ensemble means from the GFS/ECWMF advertising around
0.25" of rain, possibly higher across the north where latest
runs are showing low (10-20%) probabilities of exceeding 0.50".

The end of the forecast period becomes even less certain with
the GFS favoring a clean frontal passage on Saturday with mostly
dry conditions heading into Sunday. The ECMWF camp on the other
hand is advertising a weak coastal low developing along the
frontal boundary, which would keep precip in the forecast
through Sunday. There`s support within the ensembles for either
scenario, so I have stuck with the NBM PoPs for Sunday.
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&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
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Short Term...All terminals should several hours of MVFR this
evening, with IFR possible at KHIE/KLEB/KAUG/KRKD, KCON/KMHT may
pops out of MVFR before sunrise, but the other terminals will
likely not get to VFR until about 12-13Z. VFR expected on Monday
and Monday night, but valley fog is possible at KLEB/KHIE.


Long Term...VFR expected Tuesday through at least Wednesday
night. A weak disturbance may then bring some showers through
the area later Thursday into Thursday night, possibly followed
more showers late Friday. However, these may also hold off until
Friday night and into Saturday.
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&&

.MARINE...
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Short Term...Seas continue to stay in the 5-7 ft range outside
the bays, but they will gradually subside overnight and early
Monday. Conds stay below SCA Mon afternoon into Mon night.

Long Term...A weak frontal boundary may bring a brief increase
in northerly winds late Tuesday night or early Wednesday
morning, but otherwise high pressure is expected to keep
conditions below SCA levels this week. The high starts to shift
east by Friday as a cold front approaches from the west, and
S/SW flow will increase prior to the front, but whether it`s
enough for SCA levels is uncertain. The cold front looks to
cross the waters sometime on Saturday.
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&&

.HYDROLOGY...
Any light rainfall this afternoon and tonight should not have
any sort of significant effect on river flows as they continue
to recede.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 2 PM EDT Monday for ANZ150-152-154.

&&

$$


NEAR TERM...Cempa
SHORT TERM...Cempa
LONG TERM...Combs