Lexington Weather

Lexington, Massachusetts, USA

63°F

10/12/2026 7:23pm

Lexington Conditions: Clear
Temperature: 63.0°F / 17.2°C
Dew Point: 57.7°F
Relative Humidity: 83%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.73 in Rising Slowly
Visibility: 10 miles
Rain Today: 0.21 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 092352
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
752 PM EDT Fri Oct 9 2026

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

&&

.KEY MESSAGES...

- Breezy through sundown, then mostly clear and dry with
  decreasing winds tonight through Saturday. 

- The next quick moving round of rain comes Sunday afternoon and
  evening, continuing overnight and exiting Monday morning. 

- Quick round of rain around mid week, then dry weather returns
  by Thursday.

&&

.DISCUSSION...
KEY MESSAGE 1...Breezy through sundown, then mostly clear and
dry with decreasing winds tonight through Saturday.

It's been a partly sunny day but also quite breezy with a mixing 
depth to 800 mb, supporting westerly wind gusts in the 25 to as 
much as 35 mph this afternoon. Expect those conditions to
continue through sundown, bringing a decrease in gust speeds as 
the mixed layer decreases. The main issue for tonight is if
winds can slacken enough to support patchy frost. A sprawling
area of high pressure centered over western NY/PA is forecast to 
move eastward overnight tonight but not really crest over
Southern New England until Saturday morning. Efficient
radiational cooling is expected tonight; there may be just
enough of wind (around 5 mph) to keep frost from developing or
in isolated coverage, and for those reasons haven't issued 
frost headlines for those non-Northwest MA zones where the 
growing season continues. If you do have crops or plants, it may
not be a bad idea to consider taking protective actions to 
prevent frost damage, but I think the coverage ends up being too
isolated. Lows forecast in the mid/upper 30s in the coolest 
outlying areas similar to surface dewpoints, and into the low to
mid 40s for the urban areas and coastlines. 
  
A chilly start to Saturday but high pressure becomes established 
across Southern New England. Much of the day features full or 
mostly-full sunshine and light northwest winds, but a canopy of
high-level clouds/cirrus will be streaming in from the south 
and southwest. Seasonable highs in the mid 60s under full sun. 
High pressure then retreats eastward by Saturday night, 
supporting lows in the upper 30s to the mid/upper 40s. 

KEY MESSAGE 2...The next quick moving round of rain comes Sunday 
afternoon and evening, continuing overnight and exiting Monday 
morning.

The latest guidance suite continued to exhibit large uncertain
with the timing of rainfall ending Monday morning. The
deterministic GFS was on the more progressive side, with many of 
the international models more closely aligned with a slower
timing and closer track to southern New England. However, there 
is agreement on the overall trend of drier conditions developing
through the day. It is the timing that will need to be refined 
with later forecasts. For now, held on to a chance of showers 
towards the Cape and islands for a time Monday morning.

The timing will also impact rainfall totals. At present,
expecting this will be a modest rainfall, with rainfall amounts 
generally between one half to one inch. A slower timing, should 
it occur, opens the door for rainfall up to 1.50", mainly
towards the Cape and islands.

A brief dry period is anticipated for Monday afternoon and most
of Monday night.

KEY MESSAGE 3...Quick round of rain around mid week, then dry 
weather returns by Thursday.  

Our region should then get clipped by a pair of low pressures,
each taking a different track. The first should pass by to our
north later Monday night into Tuesday. Its cold front likely 
does not clear the coastal waters until late Tuesday night. This
will be a period of more showery precipitation.

Another dry period is expected Wednesday though most of Thursday 
night, with high pressure moving across northern New England. 

The forecast for next Friday is uncertain. A low pressure near
James Bay could swing its associated fronts across our region 
Friday into Friday Night. Have a mention in the forecast for 
more showers some time Friday. However, this timing could be 
delayed with later forecasts.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...

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

Tonight through Saturday Night: High confidence. 

VFR. NW winds around 5-10 kt, becoming light N to NE by late
Saturday afternoon, then turning easterly Saturday night into 
overnight Sunday.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Saturday Night through Wednesday/...

Sunday: VFR. Chance RA.

Sunday Night: MVFR/IFR conditions possible. Breezy. RA.

Columbus Day: Mainly VFR, with local IFR possible. Breezy. 

Monday Night: VFR. 

Tuesday through Tuesday Night: VFR. Breezy. Chance SHRA.

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.

Through Saturday Night: High confidence.

SCAs remain in effect until 7 PM this evening to allow westerly 
gusts 25-30 kt to subside. Thereafter, gradually easing NW winds
around 15-20 kt early tonight continue to decrease to around 
10-15 kt by Saturday. Light northeasterly winds late Saturday 
into Saturday night. Seas 3 ft or less all waters. 

Outlook /Saturday Night through Wednesday/...

Sunday: Winds less than 25 kt. Chance of rain. 

Sunday Night: Low risk for Small Craft Advisory winds with
local gusts up to 30 kt. Local rough seas. Rain, slight chance
of thunderstorms. 

Columbus Day: Winds less than 25 kt. Rough seas up to 9 ft.
Chance of rain. 

Monday Night: Winds less than 25 kt. Seas up to 5 ft. 

Tuesday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain
showers. 

Tuesday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 25 kt. Seas up to 5 ft. Rain showers likely,
slight chance of thunderstorms. 

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

&&

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

&&

$$

DISCUSSION...Belk/Loconto
AVIATION...Belk/Loconto
MARINE...Belk/Loconto