Old Res Weather

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 061200
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
800 AM EDT Sat Jun 6 2026

.WHAT HAS CHANGED...
No significant forecast changes.

&&

.KEY MESSAGES...

- Another hot, summerlike day with increasing humidity.
  Thunderstorms arrive late this afternoon into tonight, a few
  of which could become strong to severe. Sunday turns cooler
  with scattered showers, but not a washout.

- Seasonable temperatures Monday, followed by another stretch of
  summerlike heat and building humidity. No notable storms next
  week, though a front may bring a period of showers and 
  thunderstorms mid to late week.

&&

.DISCUSSION...
KEY MESSAGE 1...Another hot, summerlike day with increasing 
humidity. Thunderstorms arrive late this afternoon into tonight, a 
few of which could become strong to severe. Sunday turns cooler with 
scattered showers, but not a washout.

There were no notable changes to the near and short-term forecast. 
Given a well-mixed boundary layer reaching 850-800 mb, highs should 
climb well into the upper 80s to lower 90s, remaining well above 
normal for early June, when average highs are typically in the lower 
70s. Dewpoints rise into the upper 50s to lower 60s today, leading 
to a somewhat muggier feel, though conditions should not feel 
excessively humid. For those heading to the beaches, there is a 
moderate risk for rip currents Saturday along east-facing beaches of 
Cape Cod, ocean-facing beaches of Nantucket and Marthas Vineyard, 
and south-facing beaches from Point Judith, RI to Westport, MA. 
Always check with lifeguards regarding local rip current conditions.

Confidence remains consistent that most, if not all, daylight hours 
remain dry, though a brief afternoon shower cannot be ruled out 
north and west of the I-495 corridor, likely associated with a 
prefrontal trough. Increasing heat and humidity will lead to a 
moderately unstable atmosphere, with CAPE values between 500-1000 
J/kg, though some guidance suggests locally higher values 
approaching 1500 J/kg. This should support convective initiation by 
late afternoon, roughly 5-6PM. Activity may persist after sunset, 
supported by frontal forcing, modest mid-level lapse rates near 6.5 
C/km, and increasing deep-layer shear, before weakening and shifting 
offshore by around midnight. DCAPE values are modest as well, 
approaching 800 J/kg, while 0-6 km bulk shear increases to around 30-
40 kt. Given this setup, a Slight Risk for severe thunderstorms 
continues for much of interior southern New England, with the 
primary threats being strong to damaging straight-line winds and 
locally heavy downpours as PWAT values climb to around 1.8 inches.

Sunday morning, subsidence behind the front allows for drier, albeit 
humid, conditions with a mix of clouds and sunshine. By afternoon, a 
more defined mid-level trough and associated shortwave energy move 
across southern New England, though recent guidance has trended the 
surface low farther north into the Gulf of Maine. As a result, 
rainfall appears more showery and less widespread, with the greatest 
concentration of showers, general thunder, and perhaps small hail 
mainly across eastern portions of southern New England, though the 
overall severe threat appears limited. Cooler air arrives more 
gradually, which may allow highs to still reach the upper 70s to 
lower 80s before northeast flow develops later in the evening.

KEY MESSAGE 2...Seasonable temperatures Monday, followed by another 
stretch of summerlike heat and building humidity. No notable storms 
next week, though a front may bring a period of showers and 
thunderstorms mid to late week.

Sundays mid-level trough exits east of New England by early Monday 
morning as an amplified ridge shifts toward the eastern third of the 
CONUS. The trough eventually evolves into a cutoff mid-level low 
over the Canadian Maritimes, helping to slow eastward progression of 
the ridge and supporting another stretch of summerlike temperatures 
across southern New England. Monday will likely be the coolest day 
of next week due to north-northeast flow aloft draining a cooler 
airmass southward into the region. Forecast soundings Monday 
afternoon depict a well-mixed atmosphere with the boundary layer 
extending to around 850 mb and temperatures at that level ranging 
from +8C to +12C. Naturally, the farther east, the cooler 
temperatures will be, with Cape Cod, the Islands, Boston, and the 
eastern coastal plain largely remaining in the 70s, while the 
Connecticut River Valley reaches the lower to middle 80s. Through 
much of next week, an anomalous ridge extending north toward Hudson 
Bay in Canada favors mainly dry and increasingly hot conditions. 850 
mb temperatures rise to around +15C Tuesday, then increase to around 
+18C Wednesday through Friday. This should support highs in the 
middle 80s to near 90 Tuesday, followed by upper 80s to lower 90s 
through much of the remainder of the week. The first half of next 
week should feature relatively comfortable dewpoints in the 50s. 
However, by late week, dewpoints rise into the 60s, leading to a 
more humid airmass. While outside the forecast period, there is a 
signal for heat to continue into next weekend, reflected in CPC 
outlooks depicting a Slight Risk (20 to 40% probability) for extreme 
heat across portions of the Northeast. In terms of precipitation, 
there does not appear to be anything appreciable on the horizon 
through much of next week. However, a frontal passage late in the 
week may bring a period of showers and thunderstorms as heat and 
humidity continue to build.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...

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

12Z TAF Update:

Today...High confidence.

VFR, though the risk for isolated to scattered TSRA increases
from west to east after 21Z with thunderstorms arriving for east
terminals closer to 00Z. A few storms may become strong, with 
gusty winds and lightning as the main hazards. Brief MVFR/IFR
possible within heavier storms. Winds become SW and increase to
around 10-12 kt with gusts of 20-24 kt.

Tonight...Moderate confidence.

VFR outside of scattered thunderstorms. Brief MVFR/IFR possible
within any heavier storms. Initially scattered convection may 
consolidate into a broken line of storms moving eastward into 
the ORH/BED/BOS/PVD corridor between 00- 03Z before shifting 
offshore. A few storms could remain strong early with localized 
gusty winds, though general weakening trends are favored 
overnight. SW winds shift to WSW at 5-10 kt. LLWS possible for
PVD and Cape and Island terminals through 06Z. Lower ceilings
MVFR/IFR ceilings and BR may develop around 06Z for Cape and 
Island terminals.

Sunday...Moderate confidence.

VFR, though SHRA/TS develops as early as 16Z Sunday across the 
MA/VT/NH border region and progresses south/southeast through the 
afternoon. Best chances appear from ORH eastward to the Cape and 
Islands, with lower coverage farther west. Coverage should 
diminishes roughly after 21Z. Winds become NW around 10-13 kt.
Winds shift NE closer to 00Z for east coastal terminals. 

KBOS...High confidence in TAF, though moderate confidence in
exact thunderstorm timing. 

Easterly winds this morning shifting to the SW 17-18Z. Best
window for thunderstorms 00-04Z, although can't rule out an 
earlier isolated shower or weak storm after 22Z. A few storms 
may be strong to severe in that window. Gusty winds, lightning
main hazards.

VFR through 00Z Sunday. ENE winds become SW around 16-17Z. TSRA 
possible after 23Z.

KBDL...High confidence in TAF.

VFR, with SW winds gusting to 20-25 kt after 17Z. TSRA possible 
after 22Z.

Outlook /Sunday Night through Wednesday/...

Sunday Night: VFR. Breezy. Slight chance SHRA.

Monday: VFR. Breezy. 

Monday Night: VFR. 

Tuesday: VFR. Breezy. 

Tuesday Night: VFR. 

Wednesday: VFR. Breezy. Slight chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Saturday and Sunday...High confidence.

Small Craft Advisories have been expanded for Saturday afternoon 
through Saturday night across the southern waters, eastern waters, 
and Cape Cod Bay for a combination of SW wind gusts up to 25 kt and 
building seas of 4-6 ft.

There is also a risk for thunderstorms capable of frequent 
lightning, heavy downpours, and localized strong wind gusts, mainly 
after 7 PM across both the southern and eastern waters.

Another round of scattered showers and thunderstorms develops Sunday 
afternoon. There could be a period Sunday late afternoon into the 
evening where portions of the eastern waters experience northerly to 
northeast wind gusts approaching 25 kt, which may prompt an 
extension of Small Craft Advisories into Sunday night. For now, 
advisories remain in effect through Sunday afternoon.

Outlook /Sunday Night through Wednesday/...

Sunday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Seas up to 5 ft. Chance of rain showers. 

Monday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Seas up to 5 ft. 

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

Tuesday through Wednesday: Winds less than 25 kt. 

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this 
     evening for MAZ013-016>024.
RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this 
     evening for RIZ001>008.
MARINE...Small Craft Advisory from 2 PM this afternoon to 11 PM EDT 
     this evening for ANZ231-250.
     Small Craft Advisory from 2 PM this afternoon to 8 AM EDT 
     Sunday for ANZ232>235-237.
     Small Craft Advisory from 2 PM this afternoon to 2 AM EDT 
     Monday for ANZ254>256.

&&

$$

DISCUSSION...Dooley
AVIATION...Dooley/Mensch
MARINE...Dooley