Old Res Weather

Lexington, Massachusetts, USA

35°F

2/16/2025 7:17pm

Lexington Conditions: Clear
Temperature: 35.1°F / 1.7°C
Dew Point: 32.4°F
Relative Humidity: 90%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.00 in Falling Slowly
Visibility: 10 miles
Rain Today: 0.01 in
UV Index: $VPuv None

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 100817
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
417 AM EDT Mon Aug 10 2026

.WHAT HAS CHANGED...
Forecast remains on track.

&&

.KEY MESSAGES...

- Above normal temperatures and humidity continues through
  Tuesday. Relief from the heat & humidity comes late week.

- Unsettled weather continues this week with shower and 
  thunderstorms chances returning this evening as well as 
  Wednesday night/Thursday morning.

&&

.DISCUSSION...
KEY MESSAGE 1...Above normal temperatures and humidity 
continues through Tuesday. Relief from the heat & humidity 
arrives for the weekend.

After a brief respite from the humidity this morning, dewpoints
will start climbing back into the upper 60s to low 70s once the
sun comes up. Temperatures should be a tad cooler today.... 
roughly 85-89 instead of the 90+ we've been seeing lately. 
Humidity will linger through Tuesday, but both temperatures and 
dewpoints will slowly begin to trend lower throughout the week, 
bringing much needed relief to southern New England by Friday. 
High temps heading into the weekend likely near 80 with 
dewpoints dropping into the 50s, possibly even the 40s in the 
higher elevations.

KEY MESSAGE 2...Unsettled weather continues this week with 
shower and thunderstorms chances returning this evening as well 
as Wednesday night/Thursday morning.

A passing cold pool across northern New England should help to 
generate CAPE values of 750-1,250 J/kg by late this afternoon. 
Combined with a one-two punch from a passing warm front and 
trough axis moving through southern New England, some scattered 
showers and thunderstorms could pop later this evening. CAM 
guidance is once again struggling to resolve these storms, with 
some models indicating storms over NW MA, others show W CT, and 
others still keep storms confined to the Albany/NYC metro 
regions. Confidence is on the lower end as far as timing and 
placement, but currently thinking late afternoon into the sunset
hours with highest chances for a strong to severe storm forming
along the CT River Valley. A few showers could stray as far 
east as the ORH-PVD corridor; however, if these showers move 
that far east, they should be sub- severe.

Tuesday and Wednesday should remain dry and mostly sunny, 
pleasant days. But by Wednesday night/Thursday morning, a low 
pressure system sitting over the Hudson Bay will be pushing 
south/southeast into southern Quebec and New England. A few 
associated upper-level shortwaves and a cold front will likely 
be the catalyst for another round of thunderstorm chances; 
however, the main limiting factor will be the time of day the 
front pushes through. If the front hits the eastern MA coast by 
early Thursday afternoon, we'd expect weaker instability and a 
lower thunderstorm risk. However, if the front stalls or moves 
slower, then the risk for storms would increase, and so would 
the chance for any one storm to reach severe levels.

&&

.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: 

Today: Generally high confidence, but moderate confidence on 
timing TSRA and seabreezes. 

Mainly VFR; hazy-looking skies from smoke could return later 
this afternoon. TSRA looks to develop late in the day, starting 
as soon as 20-21z at BDL and ORH, then move E/ESE through 02z, 
and these could be strong with brf IFR visbys and strong winds. 
Indicated VCTS for BDL/ORH as these two TAF sites have best shot
at TSRA with PROB30 at PVD. Lower confidence in showers 
reaching BOS. Light NW winds flip to SW around 5-10 kt; BOS 
looks to seabreeze to an ESE direction around 5-10 kt, but it 
could be short-lived than a typical seabreeze with SW winds 
around 10 kt shown by 21z. 

Toight: High confidence. 

VFR. SW winds shift to W around 5-10 kt after TSRA ends/moves 
offshore after 03z.

KBOS Terminal...Moderate confidence in TAF. Generally VFR. 
Possible BKN250 develops this afternoon if enough wildfire smoke
reaches the region. Seabreeze likely around 15z, but lower 
confidence on when it will kick back SW. SHRA/TSRA possible 
after 23z today, but confidence is too low to include in TAF.

KBDL Terminal...Moderate confidence in TAF. Generally VFR. 
Possible BKN250 develops this afternoon if enough wildfire smoke
reaches the region. Higher chance of TSRA after 20z. Any storms
that do form could be on the stronger side with gusty winds, 
frequent lighting, and brief IFR visbys.

Outlook /Tuesday Night through Friday/...

Tuesday Night through Wednesday: VFR. 

Wednesday Night: VFR. Chance SHRA.

Thursday: VFR. Breezy. Chance SHRA, slight chance TSRA.

Thursday Night: VFR. Slight chance SHRA.

Friday: VFR. Breezy. 

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Tuesday... High Confidence.

Winds return to SW this morning. Local sea breezes along the 
east coast of MA. Relatively light seas across the waters 
through tonight. Could see some breezy winds near 20kts later 
this evening into Tuesday morning.

Outlook /Tuesday Night through Friday/...

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

Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers, slight chance of thunderstorms. 

Thursday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft. Chance of rain showers. 

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

&&

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

&&

$$

DISCUSSION...McMinn
AVIATION...McMinn
MARINE...McMinn