Area Forecast Discussion
National Weather Service Boston/Norton MA
122 PM EDT Tue Jun 9 2026
.WHAT HAS CHANGED...
No significant forecast changes.
KEY MESSAGES
- Dry conditions and low humidity continue through tonight
leading to another pleasant day.
- Diurnal thunderstorms possible Wednesday through Friday,
with above normal temperatures peaking on Friday.
- Temperatures remain warm, but humidity decreases, throughout
the weekend, while uncertainty remains high regarding
potential for rain showers.
.DISCUSSION...
KEY MESSAGE 1...Dry conditions and low humidity continue
through tonight leading to another pleasant day.
The high pressure system sitting south of Long Island will
continue to slowly meander further south throughout today,
allowing for the continuation of dry conditions and mostly clear
skies. Temperatures will continue to warm over the next week,
aided by southwesterly flow, bringing today's high temperatures
well into the 80s, with the exception of the immediate south
coast, Cape, and Islands, where temperatures should remain in
the low to mid 70s. Dewpoints will remain generally below 55, so
humidity levels will remain quite comfortable despite the warm
temperatures.
KEY MESSAGE 2...Diurnal thunderstorms possible Wednesday
through Friday, with above normal temperatures peaking on
Friday.
As the high pressure system moves south, dew points will surge
generally in the mid to upper 60s... possible to near 70 degrees
in some areas. While the combination of heat and humidity will
create enough instability for elevated chances for the
development of scattered showers and thunderstorms, several weak
disturbances moving through the upper atmosphere could help
trigger this activity, particularly during the afternoon and
evening hours.
There remains little indication of a widespread severe weather
event at this time. Guidance continues to indicate a possible
weak warm front, somewhat limited instability, and weaker wind
shear on Friday. Even so, a few stronger storms cannot be ruled
out. The latest CSU machine-learning guidance continues to
indicate a 5 to 15 percent probability of severe weather
Thursday into Friday, with slightly higher probabilities of 15
to 30 percent across portions of Connecticut. Forecast
confidence regarding thunderstorm coverage and intensity should
improve as higher-resolution guidance becomes available over the
next couple of days.
Confidence is slowly increasing that heat and humidity could
pose a risk, especially Thursday and Friday when heat index
values may approach 100 degrees in parts of the Connecticut
River Valley. These values are associated with moderate to major
heat impacts, increasing the risk of heat-related illness for
anyone spending extended time outdoors without adequate
hydration or access to cooling.
KEY MESSAGE 3...Temperatures remain warm, but humidity
decreases, throughout the weekend, while uncertainty remains
high regarding potential for rain showers.
By the weekend, a mid-level ridge is expected to strengthen
over southern New England, promoting rising heights aloft and a
somewhat drier air mass. Some ensemble guidance is even
indicating a quick low spinning up over southern New England
Saturday or Sunday, which introduces the potential for some
spotty rain showers. Regardless, temperatures will remain quite
warm, but dew points should fall back into the 50s, resulting in
noticeably more comfortable conditions.
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
18z TAF Update...High confidence.
VFR conditions continue into much of Wednesday. Some MVFR to
localized IFR conditions may overspread parts of the region from
southwest to northeast by early evening Wednesday along with a
few showers. Showers become more likely Wednesday night, but
coverage is still relatively uncertain.
Gusts will diminish this evening, but may linger a bit longer
near the upper Cape/Buzzards Bay area. For Wednesday, gusts to
around 20 kt may make a return by the mid/late morning hours. SW
winds will persist through tonight and into Wednesday before
shifting more S Wednesday night in the wake of a passing warm
front.
KBOS Terminal...High confidence in TAF.
KBDL Terminal...High confidence in TAF.
Outlook /Wednesday Night through Sunday/...
Wednesday Night: Mainly VFR, with areas IFR possible. Breezy.
Chance SHRA, slight chance TSRA.
Thursday: VFR. Chance SHRA, slight chance TSRA.
Thursday Night through Friday: Mainly VFR, with local MVFR
possible. Slight chance SHRA, slight chance TSRA.
Friday Night: VFR. Chance SHRA, slight chance TSRA.
Saturday: VFR. Slight chance SHRA, slight chance TSRA.
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through Wednesday Morning...High confidence.
High pressure centered across the mid-Atlantic states will
continue to slowly sink southward through Tuesday night, with
winds already shifting SW. Good mixing over the land should
yield SW wind gusts around 25 knots across our nearshore
southern waters Tuesday afternoon, prompting the continuation of
Small Craft Advisories. The rest of the region should generally
remain below small craft advisory criteria through Wednesday
morning.
Outlook /Wednesday Night through Sunday/...
Wednesday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Seas up to 5 ft. Rain showers, slight chance
of thunderstorms.
Thursday: Winds less than 25 kt. Local rough seas. Slight
chance of rain showers, slight chance of thunderstorms.
Thursday Night: Winds less than 25 kt. Seas up to 5 ft. Chance
of rain showers, slight chance of thunderstorms.
Friday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Friday Night through Saturday: Winds less than 25 kt. Slight
chance of rain showers.
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 7 PM EDT this evening for
ANZ231>236.
DISCUSSION...McMinn
AVIATION...Frank/Hrencecin
MARINE...McMinn