868
FXUS61 KGYX 280210
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
1010 PM EDT Mon May 27 2024

.SYNOPSIS...
A warm front will lift north, passing through the region
tonight. A cold front then passes overhead Tuesday. An upper
level trough slowly crosses the region Wednesday through Friday
with more scattered showers and near seasonable temperatures.
High pressure passes south of the area this weekend.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
1010 PM Update...No significant changes to the going forecast
with only minor tweaks to align with observed trends. Main band
of rain has overspread NH into western ME with area gauges
showing the heaviest rainfall rates of 0.5 to 0.75 inches per
hour. Total amounts thus far topping out around 1 inch across
the higher terrain of SW NH. The threat for convective processes
remains low and given the recent trends the threat for flooding
is low.

7 PM Update...Have mainly refined PoPs based on latest trends
in Hi Res guidance, which did not result in any significant
changes to the going forecast. Latest RAP analysis shows
instability remains south and west of the area with recent CAMs
showing some pockets of weak elevated instability crossing the
area with the main batch of rain. Have trimmed back thunder
coverage tonight because of these trends and there has also been
a slight downward trend in QPF. Nevertheless, with a plume of
high PWAT air sliding over the area will be watching for bouts
of moderate to heavy rain with recent runs of the HRRR
suggesting rainfall rates may approach 0.5 to 0.75 inches per
hour. Rain will end west to east tonight starting just after
midnight along the CT Valley and exiting eastern zones around 6
am.

Previously...

A large area of low pressure will continue to track through
southern Canada tonight. This will allow a cold front to push
east and into New England. Ahead of this front, plenty of
moisture will be streaming poleward with PWs increasing to
nearly 2 inches along a north to south axis tonight. Showers
will increase in coverage overnight along with fog being
persistent. The latest HREF has high probabilities for
visibilities to remain below a mile especially along and near
the coastline. Patchy drizzle will continue as well. However,
with the pops already running high, will not include in this
upcoming forecast package.

QPF...Locally heavy rain will fall across the region, especially
along the upslope regions of the northern mountains and
foothills.

It will be a muggy night with dew points running high, mainly in
the 55 to 65 degree range. Overnight lows will drop into the mid
50s to mid 60s as well.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
Drier air will attempt to enter the region on Tuesday behind a
departing short wave. Sunshine will allow temperature to climb
into the 70s. It will be a little cooler right along the
shoreline due to a sea breeze.

The warmth will allow for a few showers and thunderstorms to
form during the day. These will mostly be confined to the
northern mountains. Some patchy fog may develop once again
Tuesday night. The overnight lows will be relatively uniform
across the region, mostly in the 50s by morning.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Overview: A mid-level trough and cutoff low pressure system
will remain near Northern New England through Friday, which will
result in continued chances for scattered showers at times
along with near average temperatures. Drier conditions are then
likely by next weekend.

Impacts: Little to no major weather related impacts are expected.

Forecast Details: A secondary surface cold front will cross from
north to south on Wednesday, which will allow for a continued chance
for scattered showers at times. Skies will be partly sunny south of
the mountains and mostly cloudy across the mountains and far north.
Temperatures will range from around 60 to the middle 70s from north
to south. Some weak daytime instability may allow for an isolated
thunderstorm but severe storms are not currently anticipated.
Scattered showers will remain possible through Wednesday night with
cool overnight temperatures into the lower to middle 40s. The cold
front will move over the Gulf of Maine on Thursday but a weak sfc
low may develop along it. This will result in scattered showers
through much of the day, especially south of the mountains. High
temperatures will remain cool with lower 60s across the north and
upper 60s to near 70 degrees south.

Showers will likely become more isolated in nature by Thursday night
as the front and weak wave of low pressure slides north and east of
the area. Low temperatures will be mostly into the 40s. High
pressure will build to our west on Friday but latest guidance
indicates an inverted trough may develop, which would result in cool
and showery conditions once again. This portion of the forecast is
of lower confidence though as heights will be rising through the
day. Therefore, capped PoPs to slight chance at this time. High
temperatures will be into the 60s to lower 70s. Drier and
slightly warmer conditions are then likely next weekend as an h5
ridge axis moves overhead and sfc high pressure slides
eastward.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Short Term...Areas of IFR and LIFR conditions especially along
and near the coast where the fog will be most prevalent.
Otherwise, showers and a few thunderstorms will become more
numerous as the night goes on. On Tuesday, there will be a
chance for a shower or thunderstorm with IFR conditions mainly
confined to the north. Partial clearing expected Tuesday night
with mainly VFR conditions. However, there may be some patchy
fog developing during the night.

Long Term...Mainly VFR conditions are expected outside of any
scattered -SHRA and potential nighttime FG. Winds will be
primarily out of the west at or below 20 kts.

&&

.MARINE...
Short Term...SCA conditions will continue tonight as a southeast
gradient continues. Seas will be in the 4 to 6 foot range along
the outer waters. Southeast winds will veer to the south on
Tuesday with SCA conditions remaining. Periods of fog and low
stratus expected tonight into Tuesday morning, which could
cause low visibility. This improves during the day Tuesday as a
cold front passes over the waters.

Long Term...Seas up to around 5 ft are possible across the outer
waters Wednesday through part of Thursday but otherwise westerly
winds and seas will likely remain below thresholds hazardous to
small crafts.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 4 PM EDT Tuesday for ANZ150>152-154.

&&

$$


NEAR TERM...Cannon/Schroeter
SHORT TERM...Cannon
LONG TERM...Tubbs