Lexington Weather

Lexington, Massachusetts, USA

39°F

1/8/2026 11:23am

Lexington Conditions: Clear
Temperature: 39.2°F / 4.0°C
Dew Point: 38.1°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 040701
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
201 AM EST Sun Jan 4 2026

.WHAT HAS CHANGED...
Light snowfall looks even less widespread than what was 
previously forecast. Sharply colder tonight, with a modest
recovery Monday. Uncertainty remains regarding mixed
precipitation for southern New England Tuesday night into
Wednesday. Another round of rain is possible towards the end 
of next week, but timing is uncertain.

&&

.KEY MESSAGES...

- Light snow this morning with little to no accumulation. 

- Very cold conditions develop tonight into Monday morning.

- Light snow Monday evening into Tuesday morning. 

- Chance for snow and mixed precipitation Tuesday night into
  Wednesday.

- Unsettled again around Friday.

&&

.DISCUSSION...

KEY MESSAGE 1...Light snow this morning with little to no
accumulation.

Still monitoring a broad area of light reflectivity over PA/NY
state. Thus far, not seeing much drop in visibility and most
cloud bases were rather high up. Still thinking while most will
actually see some snow later this morning, it will not amount to
much, generally less than 0.5". Latest high resolution models 
slowed the timing by a couple of hours, with the snowfall now 
moving offshore by mid morning. 

Snow may linger a bit longer across the Cape and Nantucket into
early afternoon due to some ocean enhancement as winds shift 
northwest this morning. 

KEY MESSAGE 2...Very cold conditions develop tonight into Monday
morning. 

Still looking sharply colder tonight into Monday. A high
pressure moves into the central Appalachians, clearing skies and
turning winds light NW. The combination of cold advection and 
radiational cooling is expected to push temperatures into the 
single digits away from the urban centers and immediate coast, 
which should be in the teens.

KEY MESSAGE 3...Light snow Monday evening into Tuesday morning.

A warm front is still expected to shift north late Monday into
Tuesday morning along with weak low pressure that may lead to
some scattered snow showers. Guidance still indicates that this 
will not be very impactful snowfall, with totals most likely
remaining less than an inch. Higher probabilities for an inch
remain across the Berkshires and the Worcester Hills.

KEY MESSAGE 4...Chance for snow and mixed precipitation Tuesday 
night into Wednesday.

Much of Tuesday should be dry following the snow showers from
Monday night as high pressure moves in briefly ahead of a
stronger shortwave from the Great Lakes. As this shortwave and
associated surface low pressure move in, warmer, more moist air 
is advected in over southern New England. 925 mb temperatures 
begin to increase to just around 0C heading into Tuesday night 
on its approach, and 850 mb temperatures get to just above 0C. 
With this warmer air aloft and colder air still at the surface, 
mixed precipitation across much of southern New England is a 
solid possibility. Latest ensemble guidance still has low probs 
for any significant ice accumulation, but it is not completely 
negligible. Soundings continue to favor this period of freezing
rain before switching to all rain as surface temperatures 
increase heading into Wednesday morning. As this event still 
remains a few days out, a number of details still need to be 
ironed out and should become clearer as we get closer to it.

KEY MESSAGE 5...Unsettled again towards the end of the week.

As the midweek system makes its exit, mid-level ridging and
surface high pressure with it make a return ahead of another
disturbance approaching towards the end of the week. This will 
not last long, however. Significant discrepancies remain across 
the guidance at this time, but the general pattern has a
stronger shortwave beginning to make its way east from the
central US. NAEFS guidance indicates enhanced moisture with this 
system; PWATs are 1-2 standard deviations above average heading 
into the weekend. Temperatures aloft are also notably warmer
across ensemble guidance. A rain event for southern New England 
towards the end of the week is what's favored at this time, but 
current confidence is low since this event is still multiple 
days out.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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

Today...High confidence.

VFR with pockets of brief MVFR within any snowfall this morning. 
Light snow ends from W to E between 11-15Z. Light SN may linger
through about 17Z across the Cape and Nantucket as winds shift 
NW this morning.

Tonight... High confidence.

VFR. W to NW winds between 5-10 kt early on, diminishing towards
the morning hours Monday.

Monday...High confidence.

VFR for most. Areas MVFR developing during the afternoon from W
to E during the afternoon in light snowfall, mainly across the 
higher terrain.

KBOS Terminal...High confidence in TAF. 

KBDL Terminal...High confidence in TAF.

Outlook /Monday Night through Thursday/...

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

Tuesday: Mainly VFR, with areas MVFR possible. Chance FZRA,
slight chance RA.

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

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

Wednesday Night: Mainly VFR, with local MVFR possible. Slight
chance FZRA.

Thursday: VFR. 

&&

.MARINE...
Forecaster Confidence Levels...

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

High Confidence.

Relatively light winds and seas for today. Reduced visibility 
in light snow possible, especially across the eastern coastal
waters between 6 AM and noon. Area of Small Craft Advisory
conditions possible across the outermost waters later tonight
into Monday. At this time, not thinking the majority of the
waters will need an advisory, so no headlines for now.

Outlook /Monday Night through Thursday/...

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

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

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

Wednesday Night: Winds less than 25 kt. 

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

&&

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

&&

$$

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