475
FXUS61 KBOX 290728
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
328 AM EDT Sun Jun 29 2025

.SYNOPSIS...
Areas of low cloud and fog lingers across Rhode Island and
eastern Massachusetts through this morning, otherwise sunshine
and mild temperatures this afternoon. Warming up Monday through
much of next week, will have to watch for a cold front on
Tuesday that could bring strong to severe thunderstorms.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Key Messages:

* Gorgeous conditions on tap for Sunday, plenty of sunshine, and
  seasonably warm temperatures.

Expecting a gorgeous day for majority of southern New England, but
you might be waking up and thinking, really? Eastern MA and RI are
starting the day with low clouds and areas of fog, but do not worry
this erodes throughout the morning as drier moves on in.

An area of high pressure and subtle mid-level height increases to
day leads to widespread sunshine, will take a little longer for sun
to breakout over the Cape and Islands, could be as late as midday.
Today begins our next warm up. 925mb temperatures are +20C and will
result in highs in the middle 80s. Closer to the coast it will be a
few degrees cooler, likely in the low 80s. A sea breeze develops
this afternoon across eastern coastal MA, which limits the warming.
It will feel a tad muggy as well, while manageable, dew points are in
the low 60s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Key Messages:

* Heating up on Monday with highs on either side of 90F.

Fairly quiet overnight with clear skies, some indications of coastal
fog redeveloping, but not as widespread as this morning. Otherwise,
will have clear skies and light winds. Temperatures fall to the
upper 50s and lower 60s. Urban cores stay slightly warmer in the
middle to upper 60s.

Monday is quiet, high pressure moves across the region and will have
another warm day. Airmass is dry, outside of higher clouds, should
be a sunny day. 925mb temperatures range between +22C and +24C, as a
result, should have highs in the upper 80s to low 90s. And with the
flow from the south, will have increasing dew points, rising to the
mid 60s, making it feel a little warmer than actual air temperature,
heat index are 90F-93F.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Key Messages:

Key Points

 * Hot and humid conditions return Monday and Tuesday. Heat
   Advisories may be needed.

 * Strong to severe thunderstorms possible Tuesday.

 * More seasonable weather for Wednesday-Friday.

Hot and humid conditions continues Tuesday as an upper-level ridge
builds in with southwesterly mid-level flow. 850mb temperatures will
warm to +18 to +20 C, which will translate to surface temperatures
in the 90s with full sunshine. With surface flow turning southerly,
dewpoints will rise into the low 70s for Tuesday. Heat advisories
could become needed as Tuesday will have heat index at and above
95F, but will largely depend on Monday as we need two
consecutive day with 95F heat index.

500mb shortwave and surface cold front move through sometime between
Tuesday afternoon and Tuesday night. The ingredients for organized
severe thunderstorms will be available on Tuesday, with surface-
based instability between 1000-2000 J/kg and sufficient 0-6 km shear
between 30-40 kts. The main questions that remain are whether the
front arrives before peak diurnal heating ends and whether cloud
cover and early-day warm frontal precipitation clear out. The
primary hazard at this time appears to be damaging wind gusts with
low-level lapse rates of 10 C/km and strong forcing from the cold
front. The secondary threat looks to be heavy rain, with PWATS
closing in on 2.5 inches and warm cloud depths around 12 kft.
Thinking storm mode will be a linear line of storms, but cant rule
out an isolated hail or tornado threat should a discrete supercell
form out ahead of the line. And at this time, SPC Day 3 Outlook has
all of the area under a Marginal Risk for severe weather.

More seasonable weather behind the cold front for the remainder of
the week, with high temperatures in the 80s and dewpoints in the
upper 50s to low 60s. Another shortwave exits the Great Lakes late
in the week that may bring another round of showers and
thunderstorms for Thursday into Friday.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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

Through 12...Moderate confidence.

Western terminals have already improved to VFR, while eastern
terminals are IFR/LIFR. Rapid improvement to MVFR/VFR for the
eastern terminals between 10z-14z. Light winds.

Today...High confidence.

Lingering IFR/MVFR for Cape Cod and Islands through 16z to as
late as 18z, KACK could remain MVFR this afternoon. Wind shifts
to the west this morning with speeds 8 to 12 knots. Sea breeze
likely for eastern coastal Massachusetts, resulting in on shore
northeast flow a KBOS.

Tonight...High confidence.

VFR, with MVFR possible for Cape Cod and Islands. Light
northwest wind while the islands have a light west wind.

Monday...High confidence.

VFR and dry. Southwest wind 8 to 12 knots.

KBOS Terminal...High confidence in TAF trends, moderate in
timing.

IFR ceilings through 12z and MVFR viability`s. Opt`d for a
PROB30 09z-12z for brief LIFR ceilings and IFR viability`s. Have
rapid improvement between 10z and 14z, becoming VFR at latest
15z or 16z. West/southwest wind this morning, then sea breeze
kicks in closer to 18z and is from the north/northeast. Sea
breeze kicks to the south/southeast 00z-02z.

KBDL Terminal...High confidence in TAF.

Outlook /Tuesday through Thursday/...

Tuesday: Mainly VFR, with local MVFR possible. Breezy. Chance
SHRA, isolated TSRA.

Tuesday Night: VFR. Breezy. Chance SHRA, isolated TSRA.

Wednesday through Wednesday Night: VFR.

Thursday: VFR. Slight chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Today...High confidence.

Some areas of low clouds and marine fog through this morning and
then clearing this afternoon as a cold front pushes off shore. An
area of high pressure builds in from the west. Wind direction will
be dependent on your locations. Southern waters have a WSW wind, the
eastern outer waters are NW, but the near shore eastern see a sea
breeze and become NE. Seas are 2 to 3 feet.

Tonight...High confidence.

Dry. Patchy areas of coastal fog. Light NW to N wind across the
eastern waters and W to SW wind across the southern waters. Seas are
2 to 3 feet.

Monday... High Confidence.

Dry. Any morning fog erodes. SW wind 10 to 15 knots with gust under
20 knots. Seas 2 to 3 feet.

Outlook /Tuesday through Thursday/...

Tuesday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Areas of seas approaching 5 ft. Slight chance of rain
showers, isolated thunderstorms.

Tuesday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Local rough seas. Chance of rain showers,
isolated thunderstorms.

Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft. Slight chance of rain showers.

Wednesday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft.

Thursday: Winds less than 25 kt.

&&

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

&&

$$

SYNOPSIS...Dooley
NEAR TERM...Dooley
SHORT TERM...Dooley
LONG TERM...KP
AVIATION...Dooley
MARINE...Dooley