021
FXUS61 KGYX 142352 CCA
AFDGYX

Area Forecast Discussion...CORRECTED
National Weather Service Gray ME
752 PM EDT Tue May 14 2024

.SYNOPSIS...
After a warm day today, a cold front drops south through the
region bringing the chance for showers and thunderstorms this
afternoon and evening. A stalled frontal boundary will result in
unsettled, showery weather for the remainder of the week and
through the weekend with temperatures remaining seasonable for
mid May.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
745 PM Update...Showers continue to wane across the region with
the loss of daytime heating. An additional stray shower or
thunderstorm cannot be ruled out in the western and northern zones
this evening but otherwise it will remain dry with fog
development late.

Previously...

A cold front continues to sag southward into northern areas
late today and tonight, as warm air continues to spread into
southern areas. Some strong gusty thunderstorms and small hail
remain possible across northwestern areas into this evening,
with some convection starting to show up across northern New
York and Vermont.

The front makes slow southward progress into northern area
tonight and then stalls by morning. This serves to keep most of
the scattered shower activity across northern areas overnight,
while a few isolated showers make it downwind of the mountains
this evening. Most of the coast and southern areas remain dry,
but an area of marine fog looks poised to move onshore through
the MidCoast after midnight tonight. Additionally, some valley
fog is likely across northern areas that see any showers or
storms this afternoon.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Tomorrow`s forecast is looking drier and warmer overall across
interior locations outside of the mountains and western New
Hampshire. The front looks to remain stalled and gradually wash
out across northern areas tomorrow. At the same, a slow moving
low pressure system tracks south of New England, spreading
moisture northward to where there remains weak forcing along the
front. This keeps at least scattered shower activity and clouds
ongoing. Meanwhile, across the coastal plain and just back from
the shoreline, enough sunshine looks to make it through to
allow temps to warm into the 70s. A band of showers associated
with the low pressure center may push into southern New
Hampshire by late in the afternoon, but most of the rain
associated with this system holds off until after dark.

Showers and some scattered thunderstorms continue across
northern locations through the evening, before waning through
the overnight hours. Elsewhere, most of the night looks dry
until closer to daybreak on Thursday, at which time more
moisture from the low begins to push into southern New
Hampshire. Guidance on this feature continues to wobble back and
forth, but by late tomorrow night chances for rain increase
across southern areas as the low moves closer. Most of Maine and
central NH likely stay dry through sunrise on Thursday.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
A largely unsettled pattern persists over the area with fuzzy
day-to- day details, but a straight-forward broad picture
featuring daily chances for mainly-diurnal showers and
predominantly mild conditions. From a synoptic standpoint, this
is due to predominantly zonal flow over the NOAM mid-latitudes
featuring a conga line of northern and southern stream
disturbances embedded within the westerlies. At the surface,
there is good model agreement keeping high pressure centered
over Maritime Canada... and extending south along the New
England Coast. The combination of the two gives neither a total-
washout of an extended forecast, nor a dry stretch of
weather... but somewhere in between.

From a hazard perspective, slow-moving/stalled fronts with
disturbances running along them will promote potential for back-
building and/or training showers and some thunderstorms.
Looking through ensemble analysis, it appears as if deeper
moisture is shunted south on Thursday with an Atlantic low east
of Carolina ingesting much of it... which limits the
hydrological threat to some extent. However it cannot be ruled
out entirely given the uncertain specifics of the pattern,
especially if certain locales near these fronts (such as across
the mountains) see repeated rounds of rainfall.

This flow regime also promotes periods of onshore flow. Much
like the last several days however a source region from the
Maritime Canada high may not be humid enough to produce classic
"socked in" conditions along the coastal plain. Early looks at
boundary layer lapse rates suggests as much. So ultimately it
looks like we`ll enjoy nicer weather than surface wind direction
may otherwise imply with temperatures generally warming into
the 60s and 70s... modified by afternoon showers and storms, and
by the sea breeze. Ensemble solutions suggest the greatest
inroads for the marine layer comes this weekend, with the
aforementioned southern stream Atlantic low potentially drifting
north and bringing some of its moisture into the easterly flow
across the Gulf of Maine. Although humid, PoP has actually
trended down around that time given a lack of adequate phasing
and forcing.

On a personal note, this is my final forecast for
the WFO Gray office before shipping off to my next adventure.
I`ve greatly enjoyed my last 5 years in Maine, especially the
skiing and living in one of the greatest foodie cities in
America. Many thanks to those I`ve had the privilege to call
friends and/or colleagues, you`ve made this Michigander feel at
home from day one. I`ll miss the Nor`easters, but maybe not so
much the marine layer! You all are in great hands with this
group of dedicated meteorologists (and hydrologists, and
electronics technicians, and every other cog in the NWS wheel).

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Short Term...VFR continues into the evening, and through most
of tomorrow at most terminals. The exceptions will be RKD and
AUG, where a period of marine fog likely brings IFR conditions
after midnight tonight through tomorrow morning, before
gradually improving tomorrow morning. Showers and an isolated
thunderstorm are likely at HIE and LEB this evening, bringing
brief restrictions. VFR prevails most of the day tomorrow,
except at HIE where MVFR may linger most of the day. Ceilings
gradually lower again tomorrow night, with marine fog possible
at RKD and AUG again

Long Term...Low confidence in the day to day details of the
forecast exists, especially along the coast. However the pattern
suggests prevailing VFR with potential for periodic restrictions
in overnight FG or afternoon/evening SHRA.

&&

.MARINE...
Short Term...Some brief gusts to near 25kt are likely across
the southern waters into this evening, but otherwise conditions
are expected to remain below SCA levels through at least
tomorrow night. A cold front stalls north of the waters tonight,
with low pressure slowly tracking south of the waters through
tomorrow night. Areas of dense fog are likely after midnight
tonight across the eastern waters.

Long Term...Weak pressure gradient force keeps winds and seas
below SCA thresholds through the long range forecast period.
The best chance for any sort of active seas comes with a swell
off a distant Atlantic storm system, which may approach 5 ft
over the weekend.

&&

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

&&

$$

SYNOPSIS...
NEAR TERM...Clair
SHORT TERM...Clair
LONG TERM...Casey
AVIATION...
MARINE...