461
FXUS61 KBOX 031726
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
126 PM EDT Tue Jun 3 2025

.SYNOPSIS...
Summer warmth arrives Wednesday through Friday with heat peaking on
Thursday with highs possibly into the lower 90s. The main concern
for scattered showers and thunderstorms will be Friday and/or
Saturday. Temperatures return to seasonable levels this weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Messages...

* Dry tonight with lows mainly upper 40s & 50s

Mid level ridge builds east into New Eng as surface high sets up
south of New Eng. Some high clouds will move into the region but
overall looking at mainly clear skies with light SW wind developing.
Decent radiational cooling will allow low temps to drop into the 50s
with some upper 40s in the coldest locations.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
Key Messages...

* Summer warmth arrives Wed with highs mid-upper 80s away from the
  south coast but low humidity

* Some smoke/haze moves in aloft

Mid level ridge continue to build across New Eng. Surface high
moving offshore will result in a SW flow which will bring warmer low
level temps into New Eng. 850 mb temps increase to 16-17C by late
Wed with 925 mb temps 20-22C in the interior. This will result in
highs reaching mid-upper 80s away from the south coast with a few
locations in the CT valley and NE MA possibly reaching 90. Cooler
upper 70s along the immediate south coast. Dewpoints will mix out
into the low-mid 50s during peak heating so comfortable humidity
levels.

As mid level ridge moves into New Eng, expect smoke aloft to the
west to move into the region. This will start tonight and continue
into Wed before moving to the east late Wed-Wed night. This will
result in a hazy sky at times.

Another quiet night Wed night with mainly clear skies and light SW
winds. Lows will drop into the upper 50s and lower 60s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Key Messages:

* Heat and humidity continue through the late week with high
  temperatures in the mid to upper 80s and possibly low 90s Thursday
  & Friday

* Becoming more unsettled late Thursday with multiple opportunities
  for showers and thunderstorms through Saturday

* Trending cooler/drier by Sunday and Monday

Thursday and Friday

High heat and humidity peaks on Thursday as dewpoints surge under
continued southwest flow. Many locations in southern New England are
expected to experience dewpoints into the mid 60s on Thursday
afternoon. 925 hPa temps continue to rise as well, likely between
22C-25C, which supports surface temperatures in the upper 80s to low
90s on Thursday afternoon. Skies will start to cloud up Thursday
afternoon as well, as a weak pulse of short-wave energy traverses
over The Northeast. Modest height falls and moderate instability,
around 1000 J/kg or so of MLCAPE, will likely result in a few
afternoon thunderstorms/downpours. Not expecting any strong to
severe storms at this time as both lapse rates and deep layer shear
are not forecast to be favorable for organized storm development.

While Friday will remain hot and humid, increasing cloud cover will
mitigate those high temps somewhat... keeping highs in the mid to
upper 80s, but unlikely to reach 90. The heat finally breaks late
Friday as a cold front pushes through the region with another round
of showers and possibly a rumble of thunder. Latest model guidance
does not support impressive instability, but a couple of hundred
J/Kg of CAPE would be enough to support a few storms. We`ll have
more details as we enter the window of high resolution guidance
later this week.

Saturday through Monday

A low-pressure system moves through The Northeast on Saturday,
resulting in yet another wet Saturday for most of southern New
England. There is some uncertainty with respect to timing of
precipitation. A few solutions support a dry first half of Saturday
with a wet Saturday evening/Saturday night. Still time to iron out
those details, but right now ensemble means are suggesting 0.5 to
0.75" of rain between Saturday morning and Sunday morning.

By Sunday, model guidance suggests low-pressure will be exiting the
region. This would be followed by a cooler/dryer end to the weekend
with a similar pattern carrying into Monday.

&&

.AVIATION /18Z TUESDAY THROUGH SATURDAY/...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

18z TAF Update...

Through Wednesday night...High Confidence.

VFR conditions continue through the period. Light SW winds tonight
and Wed night, with SW 10-15 kt Wed.

BOS TAF...High confidence in TAF.

BDL TAF...High confidence in TAF.

Outlook /Thursday through Saturday/...

Wednesday Night: VFR.

Thursday: VFR. Breezy.

Thursday Night: VFR. Slight chance SHRA.

Friday: VFR. Chance SHRA, chance TSRA.

Friday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, slight chance TSRA.

Saturday: Mainly VFR, with areas MVFR possible. Breezy. SHRA
likely, slight chance TSRA.

&&

.MARINE...
Forecaster Confidence Levels:

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

Through Wednesday night...High confidence.

High pres over the waters will result in winds and seas below SCA
thresholds through the period. Generally SW flow through the period
with gusts up to 20 kt developing during Wed.

Outlook /Thursday through Saturday/...

Wednesday Night through Thursday Night: Winds less than 25 kt.

Friday: Winds less than 25 kt. Slight chance of rain showers,
slight chance of thunderstorms.

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

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

&&

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

&&

$$

SYNOPSIS...KJC
NEAR TERM...KJC
SHORT TERM...KJC
LONG TERM...McMinn
AVIATION...KJC/McMinn
MARINE...KJC/McMinn