115
FXUS61 KGYX 051030
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
630 AM EDT Sun May 5 2024

.SYNOPSIS...
Today will feature increasing clouds followed by periods of
light rain through tonight as a frontal system crosses New
England. Conditions remain damp until a cold front crosses on
Monday, bringing warmer and drier weather for the remainder of
Monday and Tuesday. Tuesday will be especially nice with
sunshine and temperatures warming into the 60s and 70s. Rainy
weather returns for the middle and end of the week.

&&

.NEAR TERM /TODAY/...
630 AM Update...
Quick tune up of temperatures through today, but otherwise the
forecast is on track.

Previously...
Humid onshore flow continues today with thickening overcast as
rounds of rain enter the area from the west. The feature
responsible for the incoming rain is a mid- level shortwave and
an accompanying moisture axis, tracking toward the ENE on the
leading side of a broader upper level trough shifting across
Canada. Before rain arrives, boundary layer mixing is actually
expected to be pretty good in spite of the onshore flow. This
should keep ceilings a little higher, produce a steady
southeasterly breeze, and allow temperatures to warm into the
50s... closer to 50 at the immediate coast.

Western New Hampshire probably won`t be so lucky however with
rain moving in through the morning hours... ultimately keeping
temperatures mostly in the 40s to near 50. Periods of rain
ultimately overtake the remainder of the forecast area through
the afternoon and evening. Overall a dreary afternoon and
evening with rain, low ceilings, and temperatures in the 40s.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
Steady rainfall associated with the wave comes to an end from
west to east tonight, between about 10 PM and 5 AM. Rainfall
totals have trended a little upwards with latest model runs,
with 0.3-0.6 amounts likely in most places. Lower amounts are
expected near the Midcoast toward the Kennebec Valley whereas
amounts on the higher end of that envelope are most likely in SW
New Hampshire, and in the higher terrain of New Hampshire. Risk
for impacts remains low.

There will be a lag between rainfall ending and the system`s
cold front crossing, which won`t be until the daytime on Monday.
Thus low-level moisture will remain entrenched even as dry
advection starts aloft, and thus low ceilings and a fair amount
of fog development can be expected tonight.

Drier westerly flow slowly filtering down from the upper levels
should allow ceilings to lift fairly quickly over the interior
after sunrise Monday. Temperatures thus warm quickly with better
mixing and clearing skies, into the 60s and 70s. The marine
influence however will likely cause low clouds to cling to the
coast into the Maine Capitol district for a few hours longer,
until the cold front crosses in the early afternoon... with
highs in the low- to mid-60s.

Finally, lingering low- and mid-level moisture combined with
strong surface heating may spark a few convective showers as the
cold front crosses Monday afternoon. With weak forcing though,
I`m not expecting much to come of it except for perhaps a brief
downpour.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
The 500 Mb pattern across the N Hemisphere remains very blocky,
with mostly moderate amplification, through much of next week
but more amplified troughing to our W. This will act as a wave
generator, and allow weak waves to move across N England over
several days mid to late week, with cooler onshore flow likely
again, at least part of the time.

Monday and Tuesday should be decent, although, could see some
lingering SHRA early Monday, which may linger through midday in
the mtns. Morning clouds give way to at least partly sunny skies
in the afternoon as well. Overall the day should show gradual
improvement. 850 MB temps approaching +10C should allow for for
temps to rise into the 70s across much of the area, with mainly
SW winds. Models suggesting more of a turn to the S along the SW
ME which will not be a full sea breeze there, at least until
late in the day, and highs on the coast should be mostly in the
mid to upper 60s, which will be similar to the mtns. Mon night
looks mainly clear and cool, with lows mostly in the 40s, but
might only fall into the low 50s in srn NH. Tuesday looks
slightly warmer than Monday, and with more sun as well, as sfc
high crosses the region. Highs will once again be in the 70s
most place, but could reach into the upper 70s in srn NH. The
coast and mtns once again top out in the mid to upper 60s.
Tuesday night we start to cloud up late with lows in the 40s
once again.

Things go downhill Wed as we get into a flatter pattern with a
weak ridge that gets hit by waves from 500 mb closed low
meandering over the west and central US. This will keep sfc high
to the N with a series of lows riding to the S of it, and allow
for mostly onshore flow and rounds of showers /not unlike what
we saw earlier this week/. While it is not likely to rain every
period in the extended, it also not likely to clear that much
either in between the bouts of showers, and highs are likely to
remain below normal, mainly in the 50s most days, occnly
reaching into the low to mid 60s in some spots. This pattern
looks like it will hold into Saturday, bu any stronger wave that
kick the closed low more quickly to the E, could kick this
pattern out of the area, so confidence is low late in the
forecast.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
Short Term...Widespread MVFR to IFR CIGs this morning eventually
give way to IFR/LIFR tonight as RA overtakes the region. Winds
meanwhile are forecast to remain AOB 10 kts out of SE today,
turning S tonight. RA ends, though restrictions are likely
maintained in the form of BR/FG tonight. Trending to VFR Monday
morning, closer to mid-day for RKD with SW/W winds.

Long Term...Mainly VFR expected Monday into Tuesday night. By
Wed and Thu we will be in a familiar pattern with showers and
mainly onshore flow, so flight restrictions a good bet during
the period.

&&

.MARINE...
Short Term...SE winds increase today with rain and some fog
developing through the afternoon and evening. Periods of rain
continue overnight with SE winds turning S, peaking around 20
kts Mon morning as rain exits east through the waters. Light SW
winds and 3 ft seas expected for Mon.

Long Term...Winds/seas stay below SCA levels through the period
although SE winds will start to pick up a bit on Wed/Thu.

&&

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

&&

$$

NEAR TERM...Casey
SHORT TERM...Casey
LONG TERM...Casey/Cempa