552
FXUS61 KBOX 080536
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
136 AM EDT Sat Jun 8 2024

.SYNOPSIS...
Cooler tonight, then mainly dry and seasonable conditions
Saturday. Scattered showers on Sunday with diminishing rain
chances through Tuesday. Warming and drying trend Wednesday
and Thursday, before unsettled conditions return to round out
the weekend.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
10 PM update...

Scattered showers moving across SNE this evening, supported by
mid level shortwave and pronounced cooling aloft. Some marginal
instability but this is all below a strong mid level cap which
is limiting vertical growth. Expect a few showers to move
into central and eastern MA during the next few hours. Mainly
dry conditions after midnight but still can`t rule out an
isolated shower overnight as core of coldest air aloft settles
over the region 06-12z.

Stratus and patchy fog impacting the Cape/Islands. Vsbys have
improved but probably won`t see much clearing of the low clouds
until after 06z when winds shift to W behind the weak cold
front.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
Trending less humid for Saturday, but still the low risk for a
spot afternoon shower. The greater risk will be towards northern
New England. A stronger west wind should keep the seabreeze at
bay, meaning high temperatures along the immediate east coast.

Clearing for a brief time Saturday night. More clouds and a risk
for showers could arrive late Saturday night ahead of another
weak low pressure. Above normal temperatures continue.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Highlights

* A mix of showers and sunshine on Sunday

* Some spot showers possible Monday/Tuesday before what looks to
  be a drying trend mid week

* Unsettled conditions possibly return late next week with
  trough developing in the vicinity of the northeast


Sunday...

Sunday is shaping up to be the wettest day of the long term
period with cutoff low quasistationary in southern/central
Quebec. Southwest surface to 925mb flow will allow
PWATs/dewpoints to surge back above 1.25"/mid 60s. More robust
shortwave, at least compared to what we`ve seen the last few
days, will scoop across the northeast beginning Sunday morning,
but is rather slow to move seaward so should produce showers for
the better part of the day. Still, the day doesn`t look like a
washout, but anyone with outdoor plans may want to pack an
umbrella.

Thunderstorm potential remains low on Sunday with modest CAPE,
between 400-600J`kg, but as is often the case here in SNE, mid
level lapse rates are lackluster, perhaps just touching 6.5C/km.
So, while we can`t rule out a few rumbles of thunder in the
strongest cold pool convective showers, we do not anticipate
severe weather.

Monday and Tuesday...

Upper level cutoff shifts northeast of the region to start the
work week, but lagging shortwave trough will yield scattered
shower activity for Monday and Tuesday, particularly across
northern Massachusetts, with lingering cold pool aloft (850mb
temps may drop as low as 0C across upstate NY late Monday). Cold
pool showers will be fighting against a drying column as PWATs
again drop to 0.75", so overall expect shower activity to be
much more sparse compared to Sunday. Expecting more sun than
clouds both days with diurnal cumulus developing each afternoon.
Even with cold pool aloft, W/NW downsloping should support
temperatures slightly above to near normal, in the mid to upper
70s, perhaps touching 80F in the warmest locations.

Mid to Late Week...

Very persistent trough/cutoff upper low finally relinquishes
its grasp on southern New England by Wednesday as ridging builds
in from the southwest. There remains uncertainty in how strong
ridging will be, but it should provide a brief lull in unsettled
conditions as high pressure settles in the vicinity of the
region through Thursday. Temperatures also look to trend in a
warmer direction as we progress through the week as southwest
winds develop behind the departing trough. Global guidance shows
another trough sliding southeast from the Great Lakes/southern
Ontario to round out the work week/start next weekend, but
remains varied in timing and strength of the feature. So, while
it looks like unsettled conditions will return by
Friday/Saturday, specific details won`t be sussed out for
several days.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Forecast Confidence Levels:

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

06z TAF update...

Through 12z...

VFR. Patchy IFR stratus and fog over outer Cape will improve
to VFR by 07z.

Today...High confidence.

VFR. Sct-bkn cu around 5k ft developing 14-17z with a brief
shower possible, mainly north of the MA Pike. W wind gusts to
25-30 kt developing by midday, winds more SW over Cape/Islands.

Tonight...High confidence.

VFR, with lowering cigs late across interior MA and CT as
showers move in from the west. W-SW wind 5-10 kt.

Sunday...Moderate confidence.

Areas of MVFR cigs developing as a period of showers move across
the region. Mostly SW wind 5-15 kt.

KBOS TAF...High confidence.

KBDL TAF...High confidence.

Outlook /Sunday Night through Wednesday/...

Sunday Night: Mainly VFR, with local MVFR possible. Breezy.
Chance SHRA.

Monday: Mainly VFR, with local MVFR possible. Breezy. Slight
chance SHRA.

Monday Night: VFR.

Tuesday: Mainly VFR, with areas MVFR possible. Slight chance
SHRA.

Tuesday Night: VFR.

Wednesday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.

&&

.MARINE...
Forecaster Confidence Levels:

Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.

High confidence through Saturday.

SW to W winds develop overnight. Before that happens, areas of
poor visibility in fog around the Cape and islands. Improving
visibility late tonight through Saturday night. A few gusts up
to 25 kt possible Saturday afternoon. Otherwise, expecting seas
to gradually subside tonight. Small Craft Advisory continues for
marginal 5-foot seas across the outer southern coastal waters.

Outlook /Sunday Night through Wednesday/...

Sunday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers.

Sunday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers.

Monday: Winds less than 25 kt. Seas locally approaching 5 ft.

Monday Night: Winds less than 25 kt.

Tuesday: Winds less than 25 kt. Slight chance of rain showers.

Tuesday Night through Wednesday: Winds less than 25 kt.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 5 AM EDT early this morning for
     ANZ255.

&&

$$

SYNOPSIS...Belk/KS
NEAR TERM...KJC
SHORT TERM...Belk
LONG TERM...KS
AVIATION...KJC/KS
MARINE...Belk/KS