181
FXUS61 KBOX 070843
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
443 AM EDT Mon Sep 7 2026

.WHAT HAS CHANGED...
Issued a Rip Current Statement for east-facing beaches in
Massachusetts as well as the islands.

&&

.KEY MESSAGES...

- Pleasant weather for the Labor Day Holiday with low humidity
  and mild temperatures. The dry and pleasant conditions
  continue through Wednesday.

- Unsettled weather returns mid to late week but the threat for
  flooding and severe weather appear low at this time.

&&

.DISCUSSION...
KEY MESSAGE 1...Pleasant weather for the Labor Day
Holiday with low humidity and mild temperatures. Dangerous rip
currents continue at east-facing beaches through most of the
day. The dry and pleasant conditions continue through
Wednesday.

4am Update: Went ahead and issued a Rip Current Statement for
east-facing beaches as well as the islands. Numerous off and
near-shore buoys are still reporting elevated wave periods of
8-10 seconds, which is favorable for the formation of rip
currents and locally hazardous swimming conditions.

A tranquil Labor Day Holiday is on tap as high pressure builds over
the Northeast. Aloft, these changes are driven by a broad 500 mb
ridge sprawling from the mid south into the Northeast. Looking at a
cool start to the morning after tonight`s radiational cooling.  The
vast majority of locations will wake up to lows this morning in the
lower to mid 50s with isolated 40s in favored valley locations.
After a cool start, there`s a lot to look forward to with regards to
today`s sensible weather. Temperature-wise it`s a seasonably mild
day with highs warming into the mid and upper 70s. To further
solidify today as a peak weather day humidity levels will certainly
be fall-like with dew points in the 40s and low 50s. Only caveat
will be a somewhat gusty NW wind. A modest low-level jet of 25-30kts
combined with a well-mixed boundary layer will yield gusts up to 20
mph. On Tuesday, the deeper mid-level trough continues to shift
further eastward as a mid-level ridge continues to build in from the
west. 925mb temperatures warm to +17-18C yielding high temperatures
in the upper 70s with locations potentially hitting the 80 degree
mark in the valleys. High pressure in place will support mainly dry
conditions.


KEY MESSAGE 2...Unsettled weather returns mid to late week but the
threat for flooding and severe weather appear low at this time.

By Wednesday, the mid-level ridge begins to break down and the
pattern becomes more more zonal by Thursday. Guidance continues
to show a series of shortwaves and low pressure systems passing
N of the region with their associated frontal boundaries
bringing chances for precipitation during the second half of
the week. Any boundaries that pass through the region will be
accompanied by a plume of above normal moisture, rising to
160-190% of normal by early Thursday yielding PWATS of 1.5"
approaching 2.0". The positioning of an upper jet should supply
ascent for periods of showers. There is spread across guidance
in the finer details of the timing of the waves which will
influence timing of the showers. A shortwave pushes through
sometime Wednesday evening/night triggering the first round of
showers which should taper off through the morning Thursday (at
latest). The next wave moves through late Thursday/Thursday
Night bringing another round of showers. With the timing of the
waves still variable across guidance this leaves some
uncertainty in thunderstorm/downpour potential. There will be
plenty of moisture to support downpours; however, the timing of
the wave would need be early enough to tap into the marginal
instability build through the day for convection. For now, we
are not seeing a strong signal for severe or flash flooding,
more likely periods of showers with light accumulations outside
of any isolated storms/downpours. An 850mb 35- 45kt LLJ shifts
across southern New England into Thursday. There does raise a
flag for potentially gustier winds; however, this will come down
to how well we can mix down from 850mb or even 925mb. If things
align, ensembles show potential for gusts in the 20-35 mph
range on Thursday across the land and coastal waters. Still
plenty of details to work out in the pattern before we come into
better agreement about the gusts, but something to watch for
now.

Temperatures Wednesday/Thursday lean near to slightly above normal
with temperatures in the mid to upper 70s. A cold front pushes
through early Friday bringing a cooler airmass this will support
highs in the upper 60s low 70s.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

06z TAF Update:

Through 12z: High confidence.

VFR with limited cloud cover. Still monitoring the risk for some
patchy valley fog in cooler spots between 09-12z. Most likely
spots for patchy fog will be across interior terminals like BDL.

Today and Tonight: High confidence.

VFR. NW winds increase to around 8-14 kts after 12Z with
potential for occasional gust up to 18 kts after 14Z. Winds
decrease 22-00Z becoming WNW tonight.

KBOS Terminal...High confidence in TAF. NW winds this morning increasing
to 8-13 kts after 12Z with a few occasional gusts up to 18 kts
possible after around 14Z. The stronger NW winds should more
likely keep the sea breeze offshore. Winds decrease after
around 22Z shifting more to WNW around 00Z.


KBDL Terminal...High confidence in TAF.

Outlook /Tuesday Night through Friday/...

Tuesday Night: VFR.

Wednesday: VFR. Breezy.

Wednesday Night: VFR. Windy with local gusts up to 30 kt.
Chance SHRA.

Thursday: VFR. Windy with areas of gusts up to 30 kt. Chance
SHRA, slight chance TSRA.

Thursday Night: Mainly VFR, with local IFR possible. Breezy.
Slight chance SHRA.

Friday: VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Tuesday: High confidence.

SCAs continue through early this evening to allow for residual 5
ft seas to subside.

Generally light northerly winds this morning pick back up
again Monday to around 15-20 kt, then subside overnight. Seas
will continue to decrease to 3 ft or less through the day today.
Lighter W winds Tuesday decrease to 10-15 kt with similar wave
heights of 2-3 feet.

Outlook /Tuesday Night through Friday/...

Tuesday Night through Wednesday: Winds less than 25 kt.

Wednesday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 30 kt. Local rough seas. Chance of rain
showers.

Thursday: Moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Rough seas up to 9 ft. Slight chance of rain
showers.

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

Friday: Winds less than 25 kt. Seas up to 5 ft.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...High Risk for Rip Currents through this evening for MAZ007-014-015-
     019-022>024.
RI...None.
MARINE...None.

&&

$$

DISCUSSION...Mensch/FT
AVIATION...Mensch/FT
MARINE...Mensch/FT