Lexington Weather

Lexington, Massachusetts, USA

39°F

1/8/2026 11:25am

Lexington Conditions: Clear
Temperature: 39.4°F / 4.1°C
Dew Point: 38.3°F
Relative Humidity: 96%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 30.09 in Steady
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 031843
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
143 PM EST Sat Jan 3 2026

.WHAT HAS CHANGED...
Snowfall tonight into Sunday looks even less widespread than what 
was previously forecast. Bigger story is widespread cold Sunday 
night into Monday. Biggest uncertainty for the long term 
continues to be the potential for mixed precipitation including 
freezing rain Tuesday night into Wednesday. Our next round of 
wet weather looks to be around Friday. 

&&

.KEY MESSAGES...

- Light snow tonight into Sunday with little to no accumulation. 

- Very cold conditions develop Sunday night into Monday morning.

- Light snow Monday evening into early morning Tuesday. 

- Chance for snow and a period of mixed precipitation Tuesday night 
into Wednesday of next week.

- More wet weather around Friday. 


&&

.DISCUSSION...

Key Message 1...Some light snow possible overnight into Sunday. Very 
cold air follows into Monday. 

Weak high pressure to the south of New England will keep a front 
stalled across southern NH/VT into Sunday. A weak mid level 
shortwave passes overnight into Sunday and provides just enough 
forcing for scattered snow showers. High res models have very low 
QPF as PWAT values only rise to 0.25-0.3".  Snow may linger a bit 
longer across the Cape and Nantucket due to some ocean enhancement 
as winds shift northwest Sunday morning. Overall, while most 
locations will see snowfall overnight, accumulations will mostly 
be less than 0.5". 

Other story will be much colder air arriving behind the system later 
Sunday into Sunday night. Transient area of high pressure will 
provide clear and calm conditions Sunday night, sufficient for 
substantial radiational cooling. Opted to go with the NBM 10th 
percentile to adjust lows down. Should see widespread single digit 
temperatures, especially N of of the Mass Pike where lows may even 
fall into the lower single digits. Elsewhere, lows fall into the 
lower teens. Thankfully not expecting apparent temps to fall much 
lower as winds will be mostly light and variable. 

KEY MESSAGE 2...Key Message...Light snow Monday evening into 
early morning Tuesday. 

High pressure in control to start the week leading to dry weather, 
clear skies, and colder temperatures as cool NW flow early brings 
dry, cold air overhead. This precedes a warm front that lifts north 
late Monday into Monday night as a weak area of low pressure slides 
overhead. This combo will lead to light scattered snow showers 
overspreading the region Monday evening and overnight. Not expecting 
this to be an impactful snowfall, with ensembles only indicating a 
30-40% chance of >1" of snow outside of the Berkshires and Worcester 
Hills (less toward the south coast of MA and RI). 

Key Message 3...Chance for snow and a period of mixed 
precipitation Tuesday night into Wednesday of next week.

Precipitation comes to an end by sunrise Tuesday and most of the day 
should be dry ahead of our next disturbance Tuesday night into 
Wednesday. As a mid level shortwave and its surface reflection move 
over southern New England it pulls moisture northward with PWATs 
approaching 0.8". The concern is that the mid level warm front will 
lead to a warm nose of above freezing air while temps at the surface 
(at least initially) remain below freezing leading to a period of 
freezing rain (changing to rain at least outside of the highest 
elevations). It's too soon to nail down details but forecast 
soundings are concerning for the potential of at least a period of 
freezing rain.


Key Message 4...More wet weather around Friday. 

High pressure returns on Thursday and our next shot of unsettled 
weather appears to be around Friday as a stronger shortwave 
approaches. At the moment the track favors a rain event for southern 
New England but it's much too soon to say with much confidence.

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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


Tonight...High confidence.

Mainly VFR becoming MVFR late. Winds become light and variable.
A chance for -SN after midnight.

Sunday...High confidence.

Light snow ends from W to E around daybreak. -SN may linger
across the Cape and Nantucket as winds shift NW Sunday morning.
Mainly VFR during the day, with brief MVFR in snowfall.

Sunday Night... High confidence.

VFR. Light and variable winds.

KBOS Terminal...High confidence in TAF. 

KBDL Terminal...High confidence in TAF.

Outlook /Monday through Thursday/...

Monday: Mainly VFR, with local MVFR possible. Chance SN.

Monday Night: Mainly VFR, with local IFR possible. Chance SN,
chance FZRA.

Tuesday: Mainly VFR, with local IFR possible. Slight chance
FZRA.

Tuesday Night: MVFR/IFR conditions possible. Chance RA, chance
FZRA.

Wednesday: Mainly VFR, with areas IFR possible. Chance RA,
chance FZRA.

Wednesday Night: Mainly VFR, with local IFR possible. Slight
chance RA.

Thursday: VFR. 

&&

.MARINE...
Forecaster Confidence Levels...

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

High Confidence.

Gusty NW winds diminish after sunset this evening. Seas 
continue to subside this morning. Expecting that all remaining 
Relatively light winds and seas for Sunday. Reduced visibility 
in light snow late tonight into Sunday morning. Area of small
craft conditions possible in the outer waters later Sunday night
into Monday. 

Outlook /Monday through Thursday/...

Monday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of snow. 

Monday Night: Winds less than 25 kt. Chance of snow, chance of
rain. Local visibility 1 to 3 nm.

Tuesday: Winds less than 25 kt. Slight chance of rain. 

Tuesday Night through Wednesday: Winds less than 25 kt. Chance
of rain. 

Wednesday Night: Winds less than 25 kt. Seas locally
approaching 5 ft. Slight chance of rain. 

Thursday: Winds less than 25 kt. Areas of seas approaching
5 ft. 

&&

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

&&

$$

DISCUSSION...BW/FT
AVIATION...FT
MARINE...FT