Area Forecast Discussion
Issued by NWS Boston, MA

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175
FXUS61 KBOX 021118
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
718 AM EDT Sun Jun 2 2024

.SYNOPSIS...
High pressure continues to move over New England, keeping the
region dry. Low chance for showers Sunday night with a weak
shortwave passing over the region. High pressure brings warm and
dry weather through the middle of next week, then the weather
pattern becomes unsettled toward the end of the week as a
frontal system approaches from the west.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
No significant changes to the forecast this morning. Quiet
weather continues. Brought temperatures and winds back in line
with observed trends.

Previous Discussion...

Surface high pressure centered near Bermuda continues the
stretch of wonderful weather across the region. Another warm
and mainly sunny day, very similar to Saturday, but do look for
clouds to return from west to east later this afternoon ahead of
an approaching weak shortwave. Given the similar setup, today`s
high temperatures should be similar to Saturday, highs return
to the lower and middle 80s. Do expect a seabreeze to develop
once again mid morning, leading to onshore flow along the coast,
the immediate coast likely few degrees cooler in the middle and
upper 70s. But all around a great day.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
Tonight: As mentioned above, a weak shortwave cuts across the
area with the focus on any spot showers in far southwest CT and
western MA. Think there is enough dry air near the surface that
these will be very light or virga, capped the POPs at 24
percent, leading to a "Slight Chance". The increased cloud cover
and the light westerly wind keep temperatures in the low 60s, a
few spots in northern MA settle into the upper 50s.

Monday: High pressure still in control, a secondary high over
the Gulf of Maine shifts north into Quebec and 500mb heights
increasing as ridging redevelops over the northeast. There could
be weak shortwave energy moving down from the north, likely only
adding some clouds, but would not be shocked if there were an
isolated brief shower, with PWATS around 0.8". Did introduce a
few area of "Slight Chance" showers, 15-20 percent, across the
CWA. Tough to say exactly where these will pop-up, but at the
end of the day, not anticipating any adverse weather. Still
fairly warm, highs return to the low and middle 80s despite an
easterly wind. That said, the immediate coast of eastern MA will
have highs in the middle 70s, perhaps the lower 70s for the
outer Cape.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Highlights:

* Tranquil and dry weather through Wed with mild temps inland,
  cooler near the coast.

* Increasing threat of showers/thunderstorms late this week and
  early next weekend. Timing remains uncertain.

Details:

Have the greatest confidence in the overall forecast details
through Wednesday. After then, significant timing differences
arise within the latest guidance suite, mainly from the impact
of a strengthening mid level shortwave leading to development of
a mid level cutoff over the Great Lakes late next week. This is
the main source of uncertainty with this portion of the
forecast.

Dry weather persists into Wednesday.

Latest deterministic guidance has sped up the onset timing for
showers to some time Wednesday night. The consensus timing
however, favors a slower onset time. As such, favored the
NationalBlend solution since it is ensemble-based, but still
only tried to trend the timing with the previous forecast. Thee
is that much uncertainty with the timing. All that said, have
the greatest confidence in at least some rainfall some time from
Thursday evening into early Friday morning as a frontal system
approaches from the west.

There is just as much uncertainty in how fast, or far, this
front gets east of southern New England into this weekend. Thus,
the risk for showers may continue into next weekend.

Near to above normal temperatures expected through this portion
of the forecast.

&&

.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
Forecast Confidence Levels:

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

Today and Tonight... High confidence.

VFR and dry. WSW to SW winds less than 10 knots will give way to
afternoon seabreezes along the coast. For the evening, will see
increased cloud cover over western terminals but still in the
VFR range.

Monday... High confidence.

VFR and dry. Wind becomes E/NE less than 10 knots. Across the
interior winds could become light and variable.

KBOS TAF... High confidence.

VFR and dry. SE to S wind becoming ESE 14-16z with winds speeds
less than 10 knots. This evening wind goes WSW.

KBDL TAF... High confidence.

VFR with light southerly winds. A very low chance for an isolated
light shower, mainly after 04z tonight.

Outlook /Monday Night through Thursday/...

Monday Night through Wednesday: VFR.

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

Thursday: Mainly VFR, with areas MVFR possible. Chance SHRA,
chance TSRA.

&&

.MARINE...
Forecaster Confidence Levels:

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

Today through Sunday... High confidence.

Continued tranquil boating conditions today and into Monday with
the dominant weather feature being an area of high pressure.

Today... High confidence.

Mainly sunny, increasing clouds late afternoon. South wind
generally less than 10 knots, an occasional gust to 15 knots.
Seas are 2 ft or less.

Tonight... High confidence.

Increased cloud cover, a rouge spot shower possible generally
for waters south and west of Rhode Island Sound. West winds
are between 8 and 12 knots. Gusts to 20 knots possible over the
southern waters, south of Block Island to Nantucket. Seas are 2
ft or less.

Monday... High confidence.

Partly to mostly sunny. Light east wind less than 10 knots. Seas
are 2 ft or less for most waters, building to near 3 ft along
the southern most outer waters.

Outlook /Monday Night through Thursday/...

Monday Night through Wednesday: Winds less than 25 kt.

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

Thursday: Winds less than 25 kt. Chance of rain showers, slight
chance of thunderstorms.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.

&&

$$

SYNOPSIS...Belk/Dooley
NEAR TERM...Belk/Dooley
SHORT TERM...Dooley
LONG TERM...Belk
AVIATION...Belk/Dooley
MARINE...Belk/Dooley