Lexington Weather

Lexington, Massachusetts, USA

51°F

10/12/2026 1:08am

Lexington Conditions: Light rain, Mist, Overcast
Temperature: 51.4°F / 10.8°C
Dew Point: 50.0°F
Relative Humidity: 95%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.83 in Falling Slowly
Visibility: 3 miles
Rain Today: 0.11 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 050547
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
147 AM EDT Mon Oct 5 2026

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

&&

.KEY MESSAGES...

- Scattered showers this afternoon into early morning Monday.

- A sharp temperature drop is then expected for the start of the
  week followed by a return to dry, fall-like conditions.

&&

.DISCUSSION...
KEY MESSAGE 1...Scattered showers this afternoon into early
morning Monday.

High pressure south of the Maritimes no longer had enough
influence to prevent clouds and scattered showers from
overspreading southern New England this afternoon. The trend of
the latest guidance suite was slightly farther south, quite
close to the 40N/70W benchmark just after midnight. Based on
this, kept the highest rainfall chances towards the Cape and
islands, while simultaneously lowering those chances farther
inland. Thinking there should be a rather sharp gradient on the
northwest edge of this storm, but there is lower confidence on
where exactly that will be. Overall, rainfall totals should
remain less than one half inch across the Cape and islands, and
generally less than one quarter inch north and west of the Cape
Cod Canal.

Thinking that most of the showers will be well offshore shortly
after midnight, and even past the southern New England coastal
waters around daybreak Monday. 


KEY MESSAGE 2...A sharp temperature drop is then expected for
the start of the week followed by a return to dry, fall-like 
conditions.

A deep low continues tracking eastward across Quebec to start
the week, with latest guidance indicating the 540dam thickness
line reaching northern New England, generally across Maine at 
its southernmost pass. The 560dam thickness line may extend 
through central MA. High pressure follows this low, which will 
aid in drying out the region and remains the main story for this
week.

With the passage of this low, colder, drier Canadian air will
plunge south, with 850 mb temperatures reaching 0C and lower 
across the higher elevations late Monday night/early Tuesday 
morning. 925 mb temperatures may also approach 0C in these same 
areas and generally remain below 10C through Tuesday night as 
well. This environment will be supportive of lows Monday night 
in the low 40s and upper 30s. Tuesday night looks to be cooler 
given some radiational effects possible with diminishing winds 
overnight and clear skies as another high pressure passes just 
to the south of southern New England.

The flow aloft shifts more WSW to SW as the low exits and high 
pressure centered to our south midweek tracks east. With the 
return of SW flow and drier conditions, more seasonable
temperatures take hold for the back half of the week. Ensembles 
also hint at the chance of high temperatures getting back to the
low 70s towards Thursday afternoon, generally across the CT
Valley, Merrimack Valley, and the coastal plain. Probabilities
currently range between 20 and 60 percent, with the highest
probabilities in the GEFS and lowest in the ECMWF ensemble.
Overall, though, highs are expected to be more so in the 60s for
the second half of the week into the weekend.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

Monday and Monday Night...High confidence.

Lingering IFR/MVFR ceilings thorugh this morning improving to 
VFR by late morning/noon. Gusty W to WNW winds 22-27 kts 
developing by early afternoon. Gusts should diminish towards 
sunset with skies clearing, though breezy WNW winds continue at 
5-15 kts overnight.

KBOS Terminal...High confidence in trends, moderate confidence 
in timing. Lingering MVFR through sunrise. Gusts begin to pick 
up by mid-morning.

KBDL Terminal...High confidence in TAF.

Outlook /Tuesday Night through Friday/...

Tuesday Night: VFR. 

Wednesday through Thursday: VFR. Breezy. 

Thursday Night through Friday: VFR. 

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Tuesday...High confidence.

Some lingering showers off Cape Cod push further offshore 
through sunrise. Gusty west winds then develop with the frontal 
passage this afternoon. Small Craft Advisories remain in effect 
for wind gusts up to 25-28 kt. In addition, seas should build to
5-7 feet across the outer coastal waters. Seas and winds begin 
to diminish late Tuesday afternoon.

Outlook /Tuesday Night through Friday/...

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

Wednesday: Winds less than 25 kt. 

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

Thursday through Friday: Winds less than 25 kt. 

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 9 PM this evening to 1 AM EDT 
     Tuesday for ANZ232.
     Small Craft Advisory from 10 AM this morning to 1 PM EDT 
     Tuesday for ANZ250.
     Small Craft Advisory from 8 AM this morning to 1 PM EDT 
     Tuesday for ANZ254.
     Small Craft Advisory from 3 PM this afternoon to 1 PM EDT 
     Tuesday for ANZ255-256.

&&

$$

DISCUSSION...Belk/Hrencecin
AVIATION...McMinn
MARINE...Belk/Hrencecin