343
FXUS61 KGYX 191949
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
349 PM EDT Sun May 19 2024

.SYNOPSIS...
Clouds and fog are expected again tonight as high pressure
gradually builds into the region. This high pressure should
clear things out tomorrow and then dominate through early next
week allowing for some seasonably warm temperatures.
Thunderstorms are possible Tuesday afternoon and then the next
chance for widespread showers will be Wednesday into Thursday as
a cold front approaches. An upper level trough will keep
scattered showers over the region Friday. High pressure builds
in from the north next weekend, bringing a return to cooler
conditions.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Impacts:
*No significant weather impacts expected

Latest RAP13 analysis shows a 500 mb ridge and surface high
pressure building into the area at this hour. However, much of
the area remains under the influence of moist northeast flow
which is helping to keep cloud cover thick this evening. Since
expected cloud cover has increased, I went ahead and increased
low temperatures for tonight. Patchy fog and clouds will keep
temperatures in the low 50s most places.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...

Impacts:
* No significant weather impacts expected

Skies are expected to be much clearer by tomorrow morning as
the 500 mb ridge and surface high pressure become better
established over the region. We should have a decently mixed day
over much of the region taking full advantage of the near 12C
850 mb temperatures. Expecting mid to upper 70s across most of
the area with points along the Connecticut River Valley maybe
even seeing 80. The coast may end up very disappointed as winds
turn onshore and cool marine air gets trapped under a steep
temperature inversion. As of now I have 60s on the coastal
plain, but this will have to be watched closely.

After a very warm day temperatures look to only drop into the
low to mid 50s with the coast a bit cooler in the upper 40s, due
to the cool onshore flow. The trapped marine air would also
give the coastal plain a good chance at another night with
patchy fog.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Overview... A building ridge along the Eastern Seaboard brings
very warm conditions for much of the week, peaking midweek.
Residual convection riding around the ridge brings a few chances
for showers and storms over several days, with the greatest
chance on Thursday as a cold front approaches from the north.
Relatively cooler air returns by late in the week and the
weekend.

Details...

The heat continues to build on Tuesday with southerly flow.
Temps warm into the 80s in most spots, with highs near 90 across
southern New Hampshire. The coast remains cooler again on
Tuesday, with highs mainly in the 70s, and 60s along the
MidCoast. Some of the high res guidance is starting to suggest
that the convection from today`s severe outbreak will be
rounding the ridge and moving into northern New England by late
in the day and into Tuesday night. While it`s difficult to have
high confidence in such a convection-driven system from a
couple days out, models have had a tendency to under-do these
features over the last few weeks. It`s certainly worth watching,
and is the reasoning to raise POPs above NBM across northern
areas Tuesday evening. Should this convection materialize, it`s
also likely to have an impact on temperatures across northern
spots going into Wednesday.

Wednesday looks to be the peak of the heat, with temps warming
into the low 90s across much of southern and western NH, and 80s
elsewhere. Even the southern coastlines warm into the 80s with
southwesterly flow, while the MidCoast warms into the 70s. As
mentioned, there`s a little less certainty across the north on
high temps where leftover morning convection could limit how
high temps rise. Scattered afternoon showers and storms are also
likely across northern areas Wednesday afternoon. There will be
another deteriorating MCS rounding the ridge again Wednesday
night, but similar to the previous night`s it`s unclear at this
point how robust this system will be by the time it reaches New
England.

Thursday remains warm, but with a downward trend in temps
underway. A cold front moves through during the daytime, with
some showers and storms accompanying it, especially across the
higher terrain. Thursday likely ends up be the warmest day for
the MidCoast, with winds turning westerly in the afternoon and
warming temps into the upper 70s to near 80. 80s are expected
elsewhere, with one more day in the upper 80s across southern
NH.

Behind the cold front, temps still look fairly warm downwind of
the mountains on Friday. Temps warm into the 70s in most spots,
with highs near 80 across southern NH. The mountains likely see
more cloud cover and get deeper into the cooler airmass,
keeping highs in the 60s.

Right now the weekend looks cooler as high pressure noses in
from the north, but the warmth won`t be far off to the south.
The high is not overly strong, and has been trending a bit
weaker since yesterday. Should this trend continue, then the
weekend would likely end up warmer with highs in the 70s, rather
than the 60s. This forecast follows closer to that trend, but
acknowledges that we could end up with a boundary of airmasses
within the CWA. This is one more item to monitor over the coming
days.


&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
Short Term...Ceilings are expected to stay MVFR/IFR through
this evening, before continuing to lower and trending most
terminals toward IFR/LIFR again tonight. Patchy fog may develop
again tonight as well. Conditions look to improve to VFR across
most of the area Monday. The only exception would be along the
coast where the marine layer may get trapped and keep ceilings
lower. Winds remain light through the period.

Long Term...Mainly VFR conditions are expected at most
terminals Tuesday through Thursday. Some coastal fog is possible
at times at RKD Wednesday and Thursday. Afternoon and evening
showers and thunderstorms bring brief restrictions Tuesday
through Thursday across northern terminals, with a lesser chance
of showers and storms elsewhere. VFR conditions likely return
by next weekend.

&&

.MARINE...
Short Term...SCA seas are expected to gradually subside
overnight, and end up below thresholds for Monday. SCA
conditions are not expected through Monday night. Onshore winds
will be gusting around 10-15 kts Monday.

Long Term...High pressure builds along the Eastern Seaboard
this week, bringing increasing south to southwesterly flow.
Areas of dense marine fog are possible by midweek. Some SCA
conditions are possible by Thursday with increasing
southwesterly flow ahead of an approaching cold front. High
pressure then builds across the waters going into the weekend.


&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 1 AM EDT Monday for ANZ150-152-154.

&&

$$

NEAR/SHORT TERM...Baron
LONG TERM...Clair