Lexington Weather

Lexington, Massachusetts, USA

31°F

1/18/2026 8:38am

Lexington Conditions: Mist, Partly cloudy
Temperature: 30.6°F / -0.8°C
Dew Point: 29.1°F
Relative Humidity: 94%
Wind: Calm, 10-min avg: Calm, gust: 5 mph
Barometer: 30.02 in Rising Slowly
Visibility: 5 miles
Snow Today: 0.0 in

Southeast Middlesex County, MA - Winter Weather Advisory - Special Weather Statement
- SEE ALL NEARBY ALERTS -

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 161125
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
625 AM EST Fri Jan 16 2026

.WHAT HAS CHANGED...

1 to 2" of snow is expected very late tonight into Saturday 
across the lower elevations of interior Massachusetts and 
northern Connecticut with 2-4" possible across the higher 
terrain of the Berkshires and northern Worcester Hills. Offshore
low pressure may bring a plowable snow to portions of the 
region Sunday into Sunday night...but the westward extent 
remains quite uncertain. We continue to have high confidence in 
a shot of arctic air later Monday into Wednesday with bitterly 
cold wind chills.

&&

.KEY MESSAGES...

- Blustery and cold today with windchills in the single digits
  above and below zero for much of the region. 

- 1 to 2" of snow is expected very late tonight into Saturday 
  across the lower elevations of interior Massachusetts and 
  northern Connecticut. 2-4" possible across the higher 
  terrain of the Berkshires and northern Worcester Hills. 

- Offshore low pressure may bring a plowable snow to portions of the 
  region Sun-Sun night...but the westward extent remains uncertain.

- Arctic cold front crosses the region later Mon bringing well below normal 
  temps, bitterly cold wind chills, along with Gales/Freezing Spray for our 
  waters into Wed.

- Some moderation in temperatures expected by Wed night-Thu with
  perhaps a period of snow.

&&

.DISCUSSION...

KEY MESSAGE 1...Much colder today behind a strong cold front 

Much colder today with highs 15-20 degrees colder than Thurs. Values 
will range from the mid to upper 20s across the interior to the 
lower to mid 30s closer to the coast. Peak winds expected through 
15z as a 45-50kt low level jet moves in behind deepening low 
pressure to the northeast. Peak gusts will likely be in the 35-45 
mph range especially in the higher terrain. Wind chills will bottom 
out in the single digits for the majority of the region this 
morning, except zero to 5 below over the Berkshires and Worcester 
Hills. 

Shortwave trough will be quick to move out today with rising heights 
and shortwave ridging moving into the region. Dry column under high 
pressure will mean colder but clear conditions today. The core of 
the coldest air aloft moves out this afternoon allowing temps to 
recover into the lower 30s, except mid-upper 20s higher elevations 
with winds gradually subsiding mid to late afternoon.

KEY MESSAGE 2...1 to 2" of snow is expected very late tonight into Saturday 
across the lower elevations of interior Massachusetts and northern
Connecticut. 2-4" possible across the higher terrain of the Berkshires
and northern Worcester Hills. 

Broad upper trough amplifies over the Great Lakes with a series of 
embedded shortwaves rotating around it. One shortwave passes to the 
north and west and brings two rounds of precipitation including 
elevation snow and rain along the coastal plain Saturday morning and 
afternoon. Still anticipating a light event with a coating to as 
much as 2 inches possible, mainly north and west of I-95. Guidance 
has continued to trend warmer for areas south and east of I-95 
bringing boundary layer temps in the upper 30s and even lower 40s 
along the coastal plain. There still may be a slushy coating in 
these locations, but impacts will be limited. 

A lull in precipitation likely develops as WAA and overrunning wanes 
Saturday morning. Another period of interior snow and coastal rain 
develops during the late morning/early afternoon as a mid level 
front moves into New Eng with area of mid level frontogenesis. 
Additional measurable snow will be mostly confined northwest of I-95 
as a warmer boundary layer will result in mostly rain in the coastal 
plain. Snow could fall moderately for a period of time Saturday 
afternoon with omega values falling to -10 to -15 ubar/sec as 
frontogenesis increases. Additional accum Saturday afternoon of an 
inch or 2 is possible in the interior Sat afternoon with total 
accumulation from very late tonight through Sat of 1-2 inches, 
much of this focused across central/W MA and northern CT with
2-4" possible in the high terrain of the Berkshires and northern
Worcester Hills. It is possible rain flips to snow near I-95 
before precip ends but not expecting more than a slushy coating 
here. 

KEY MESSAGE 3...Offshore low pressure may bring a plowable snow to 
portions of the region Sun-Sun night...but the westward extent 
remains quite uncertain.

There still remains considerable uncertainty with the westward 
extent of a potentially plowable snowfall in association with an offshore 
low pressure system Sun into Sun night. We normally do not see this much 
spread in the guidance for a day 3 forecast...but there are so many 
moving parts. The 00z GFS/NAM/ECMWF operational models keep the low 
pressure far enough east that taken verbatim would result in very 
little if any snow ever reaching as far northwest as the Boston to 
Providence corridor. However...it is more complex than that. We 
noted that some of the 00z GEFS ensembles have shifted further 
northwest. In addition...the 00z RGEM/UKMET were considerably 
further northwest and would bring accumulating snow all the way back 
across distant interior southern New England. Also of note...is that 
the GFS/ECMWF AI models continue to be considerably west of the 
traditional GFS/ECMWF models. These AI models bring a plowable 
snowfall all the way back across interior southern New England. 
While we do not have a lot of experience utilizing a lot of the AI 
guidance...that is certainly concerning. 

So in a nutshell...given all the uncertainty there probably is not a 
ton of value in a deterministic snowfall forecast Sun into Sun 
night. That being said...appears the greatest risk for a plowable 
snow might be near and southeast of the Boston to Providence 
corridor. That possibility could extend back into western MA and CT 
if the western solutions verify. And it is also possible that there 
will be little if any snowfall even into the Boston to Providence 
corridor. We do think we should see the models getting a much better 
handle on this in the next 12-24 hours.

KEY MESSAGE 4...Arctic cold front crosses the region later Mon 
bringing well below normal temps, bitterly cold wind chills, along 
with Gales/Freezing Spray for our waters into Wed.

What ever happens with the western extent of the snow shield Sun 
into Sun night...the main concern for the first half of next week 
will be a shot of arctic air. All model guidance and their ensembles 
remain in excellent agreement. An arctic cold front crosses the 
region late Mon into Mon night...bringing well below normal 
temperatures along with bitterly cold wind chills on very gusty west 
winds. The cold may peak Tue with high temps only between 15 and 25 
degrees and low temps mainly in the single digits to the lower 
teens. Wind chills will drop below zero given the windy conditions. 
Lastly...moderate freezing spray and gale force wind gusts are a 
very good bet for our marine zones. 

KEY MESSAGE 5...Some moderation in temperatures expected by Wed 
night-Thu with perhaps a  period of snow.

Deep upper trough begins to lift off to the northeast allowing for 
rising height fields. This will allow for some moderation in temps 
by Wed night into Thu. We may also see a period of snow in the warm 
air advection pattern...but plenty of time to sort that out.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...

Forecaster Confidence Levels...

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

12z TAF Update...

Today...High confidence.

VFR. W wind gusts of 25 to 35 knot with a few brief gusts up to
40 knots.

Tonight and Saturday...Moderate confidence.

VFR this evening with diminishing winds becoming southwest. 
Some MVFR conditions will develop across parts of interior 
southern New England between 6z and 12z in snow with perhaps 
some brief IFR conditions too. These conditions will continue 
at times on Sat. Generally looking at 1-2" of snow across parts 
of western/central MA and perhaps portions of far northern CT 
with perhaps some 2-4" amounts in the highest terrain. Temps 
rising above freezing should result in wet runways by Sat 
afternoon outside the highest terrain of the Berks and northern 
Worcester Hills. 

Meanwhile...across eastern MA and RI just a few brief rain/wet
snow showers with mainly VFR conditions persisting. 

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Saturday Night through Tuesday/...

Saturday Night: Breezy. 

Sunday through Sunday Night: Breezy. Slight chance SN.

Martin Luther King Jr Day through Tuesday: Windy with gusts up
to 35 kt.

&&

.MARINE...

Forecaster Confidence Levels...

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

Through Saturday...High Confidence.
 
Gusty W winds this morning with gusts as high as 40kts, especially 
in the outer waters. The cold air and increasing wave action will 
result in light freezing spray developing. Winds will begin to 
diminish later this afternoon and eventually drop to less than 20 kt 
later tonight. Brief lull arrives overnight with winds possibly 
increasing to SCA levels again Saturday afternoon.

Outlook /Saturday Night through Tuesday/...

Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Local rough seas. Slight chance of rain. 

Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Chance of rain, slight chance of snow. 

Sunday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of snow. 

Martin Luther King Jr Day: Low risk for gale force winds with
gusts up to 40 kt. Areas of rough seas. 

Monday Night: gale force winds with gusts up to 45 kt. Areas of
rough seas. Freezing spray, slight chance of snow showers. 

Tuesday: Moderate risk for gale force winds with gusts up to
40 kt. Areas of rough seas. Freezing spray, slight chance of
snow showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Gale Warning until 4 PM EST this afternoon for ANZ230>237-250-
     251-254>256.

&&

$$

DISCUSSION...FT/Frank
AVIATION...FT/Frank
MARINE...FT/Frank