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157
FXUS61 KBOX 142229
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
629 PM EDT Fri Jun 14 2024

.SYNOPSIS...
Second round of strong to severe thunderstorms expected through
early tonight ahead of a dry and pleasant Father`s Day weekend.
Several days of excessive heat and humidity are likely starting
Tuesday and lasting through next Friday.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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630 PM Update:

Activity currently near PVD-BOS developed in area of MLCAPE and
weak 0-6km shear and has shown weakening trend in past 30
minutes. Some brief wind gusts earlier (34kt at OWD) but this is
now transitioning to briefly heavy rain with minor street
flooding as airmass stabilizes with loss of daytime heating.

Next round of convection over NJ and SE NY is associated with
cold front and upper trough which will rotate through SNE later
this evening. HRRR has a good handle on this and brings it
through in a weakened state, meaning we`ll see more in way of
showers vs thunderstorms as we approach midnight, and this
activity should be heading off Cape Cod overnight.
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&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Departing cold front/deep digging shortwave will allow very, at
least for June, dry air to filter into the region on NW/N flow
tomorrow. PWATs are expected to drop to around 0.4" by 18/21Z
Saturday, yielding a gorgeous, comfortable start to Father`s day
weekend. Little cloud cover is expected, with dewpoints dropping
into the low and mid 40s by early evening. 850mb temperatures
between 8-10C will support highs in the mid 70s to low 80s.

Radiational cooling will be in play Saturday night. With very dry
airmass in place and mainly clear skies overhead, as well as
slackening winds, it is quite possible that low temperatures drop
into the low to mid 40s across northwestern MA by daybreak on
Sunday. Urban heat islands, like Boston and Hartford, will remain
our most mild localities, with lows around 60F expected.
Temperatures across the coastal plain will fall back into the
50s. This is our last shot of cool air for quite some time as
mid level ridging starts to build in to end the weekend.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Key Point:

 * Several days of dangerous heat/humidity Tue-Fri

Big story for next week continues to be likelihood of dangerous heat
and humidity starting Tue and peaking Wed-Fri. Ensembles are in very
good agreement on building strong upper ridge over eastern U.S.
through most of next week which lends increasing confidence. In
fact, 500 mb heights nearing 600 dm is something rarely seen in the
Northeast and is a very strong signal for record heat. This aligns
with EPS and NAEFS Situational Awareness Tables which show several
parameters outside of model climatology relating to temperature,
signaling potential for a highly unusual event.

We`re also seeing fairly high chances of afternoon highs well into
90s Tue-Fri, if not near 100 in some spots. More importantly,
daytime heat indices may reach as high as 105 degrees and there will
be little relief at night with nighttime heat indices in 70s.

Upper ridge also favors dry weather for much of next week, but it`s
possible we see widely scattered showers/storms, especially in Thu-
Fri timeframe as cold front approaches from Great Lakes.

&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
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Forecast Confidence Levels:

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

00z TAF Update: High confidence (70%)

Area of showers/storms moving through eastern MA/RI moves
offshore early this evening, but another round of showers with
embedded thunder should cross southern New England 02z-08z as
cold front pushes through. Expect brief lowering to MVFR/IFR.

Otherwise VFR ceilings should prevail through tonight as SW
winds veer to W-NW and N overnight, except IFR/LIFR is likely to
develop near Cape Cod and Islands. Slow improvement Sat morning
with VFR-MVFR ceilings gradually scattering out Sat afternoon
as N winds increase to 10-20kt with gusts to 25kt near coast.

KBOS TAF...High confidence in TAF (70%).

KBDL TAF...High confidence in TAF (70%)

Outlook /Sunday through Wednesday/...

Sunday through Sunday Night: VFR.

Monday: VFR. Breezy.

Monday Night through Juneteenth: VFR.
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&&

.MARINE...
Forecaster Confidence Levels:

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

Tonight:

Steady light to moderate rain with embedded thunder possible.
Winds shift WNW and decrease to 5-10 knots overnight. Seas 2-3
feet.

Tomorrow:

Rain tapers off in the morning with clearing conditions in the
afternoon. Winds turn north and gust 15 to 20mph. Seas 2-4 feet.

Tomorrow Night:

Clear conditions and generally light winds. Seas around 2-4
feet.

Outlook /Sunday through Wednesday/...

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

Sunday Night through Monday: Winds less than 25 kt.

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

Tuesday through Juneteenth: Winds less than 25 kt.

&&

.CLIMATE...
Daily Record High Temperatures...

Tuesday, June 18th

BOS - 94F (1929)
BDL - 95F (1994)
PVD - 94F (1929)
ORH - 93F (1929)

Wednesday, June 19th

BOS - 96F (1923)
BDL - 95F (1995)
PVD - 94F (1923)
ORH - 93F (1923)

Thursday, June 20th

BOS - 98F (1953)
BDL - 97F (2012)
PVD - 95F (1941)
ORH - 93F (1953)

Last Day of 100F (or greater)

BOS - 100F (07/24/2022)
BDL - 100F (07/21/2019)
PVD - 100F (07/28/2020)
ORH - 102F (07/04/1911)

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for
     ANZ230>237-251.
     Small Craft Advisory until 11 PM EDT this evening for ANZ250-
     254.

&&

$$

SYNOPSIS...KS/JWD
NEAR TERM...KS/JWD
SHORT TERM...KS
LONG TERM...JWD
AVIATION...JWD
MARINE...KS/JWD
CLIMATE...Dooley