Lexington Weather

Lexington, Massachusetts, USA

37°F

1/11/2026 11:31am

Lexington Conditions: Mostly cloudy
Temperature: 37.2°F / 2.9°C
Dew Point: 36.1°F
Relative Humidity: 96%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.65 in Falling Slowly
Visibility: 10 miles
Rain Today: 0.07 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 101730
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
1230 PM EST Sat Jan 10 2026

.WHAT HAS CHANGED...
No significant forecast changes. A Winter Weather Advisory has been 
issued for the Berkshires and northern Worcester Hills due to the 
threat of freezing rain. Confidence increasing in a period of
gusty NW winds of 35 to 50 mph Sunday night into early Monday. 
Wind Advisories remain possible for the high terrain.

&&

.KEY MESSAGES...

- Widespread rain arrives late this afternoon, areas of 
  freezing rain for locations at or above 1,000 feet in northern
  and western Massachusetts. Becoming dry and breezy on Sunday.

- Becoming windy & turning colder Sun night into Mon with a
  period of NW wind gusts of 35 to 50 mph possible later Sun 
  night. Low risk for a brief snow squall too.

- Mainly dry conditions early next week, trending more 
  unsettled by mid-week with periodic showers and a potential 
  coastal system for Friday.

&&

.DISCUSSION...
KEY MESSAGE 1...Widespread rain arrives late this afternoon, areas 
of freezing rain for locations at or above 1,000 feet in northern 
and western Massachusetts. Becoming dry and breezy on Sunday. 

With a quasi-stationary front south of New England today and an area 
of high pressure to the north, much of the daylight hours remain dry 
and somewhat mild in the low to mid-40s. The sub-tropical ridge over 
the southeast CONUS shifts NE with an robust S/SW low-level jet 
shifting the front back north late this afternoon. Riding along this 
front is a developing area of low pressure, adding to the assent 
needed to ring out these above normal PWATs. PWATs between 1.0" and 
1.2" across the coastal plain, with lower values across the interior 
at 0.8". Still, plenty of moisture to be had as this front pushes 
north. Rain totals are generally in the range of 0.3" and 0.5" N and 
W of I-95, areas S and E are between 0.6" and 1.0", with locally 
higher amounts of 1.5" mainly across the outer Cape and Islands. 

While majority of the region has rain, interior areas have freezing 
rain AOA 1,000 feet. Although surface temperatures may initially be 
marginally above freezing, forecast wet bulb temperatures near 0C 
indicate evaporative cooling will quickly lower surface temperatures 
to freezing once precipitation begins. Given a well defined warmnose 
between 900mb and 700mb, and only a shallow subfreezing layer near 
the surface, freezing rain appear more likely than sleet. 

A Winter Weather Advisory is issues for two areas across our region. 
First, eastern slopes of the Berkshires, with ice accumulations 
between 0.1" and 0.2". Second area, northern Worcester Hills, where 
less ice accumulation is anticipated, between 0.01" and 0.1". Both 
of these areas are under an advisory between 5 PM today and 10 AM 
Sunday. Plan on slippery road conditions. Drying late Sunday morning 
into Sunday afternoon as low PWATs advect into the region. Will 
notice a shift in the wind due to the surface low passing, going 
from E on Saturday, to W on Sunday. Gusts begin to increase in the 
late afternoon, becoming strong overnight. Will have to watch out 
for a few CAA snow showers or a snow squall. More on that in the 
next key message.  

KEY MESSAGE 2...Becoming windy & turning colder Sun night into
Mon with a period of NW wind gusts of 35 to 50 mph possible 
later Sun night. Low risk for a brief snow squall too.

Saturday's low pressure system will be exited over the Canadian 
Maritimes by Sunday night continuing to deepen while a cold front 
moves through southern New England. This will result in a fairly 
tight pressure gradient developing across the region. Strong CAA 
should help with the mixing down of the higher gusts aloft 
supporting gusty northwest winds Sunday night into Monday. The LLJ 
in place will be moderate in magnitude around 40-50 kts. Model 
soundings reinforce the gust potential showing a deep well-mixed 
layer. All appears supportive of gusts 35-45 mph with the higher 
gusts in that range over the high terrain and Cape/Islands. Can't 
rule out a gust to 50 mph for the Berkshires which is in the 75th 
percentile of the NBM.  With all that said, it is possible we 
briefly reach Wind Advisory criteria in areas with the highest 
probabilities for the Berkshires, Worcester Hill, and Cape/Islands. 
Confidence is increasing in the need for a short-lived advisory for 
at least the Berkshires. Stay tuned for updates on any wind 
headlines. The strongest gusts look to be most likely in the Sunday 
night to early Monday timeframe. 

We still continue to have a low risk for a weak snow squall or two 
Sunday night with the cold frontal passage and arrival of the gusty 
winds. Steepening lapse rates and residual mid-moisture in place 
should create a sufficient environment, although we are lacking in 
the surface moisture which is why coverage of any squally showers 
will likely be low. This potential is echoed by some low values in 
the snow squall parameter model fields. 

Temperatures overnight drop into the 20s for most places Sunday 
night and with the added strong winds will bring wind chills into 
the single digits and teens. 

KEY MESSAGE 3...Mainly dry conditions early next week, trending
more unsettled by mid-week with periodic showers and a 
potential coastal system for Friday.

Looking ahead to next week, the pattern aloft stays on the active 
side with a series of shortwave troughs/disturbances moving through 
the flow in the eastern portion of the CONUS. A weak shortwave drops 
south from the Great Lakes late Monday; however, it will be fairly 
moisture starved resulting in mainly dry conditions. A brief period 
of warming is likely Tuesday/Wednesday as a mid-level ridge moves 
through. A few scattered rain/snow showers are possible late Tuesday 
into early Wednesday with as a piece of weak shortwave energy moves 
through. 

There is general agreement among ensemble guidance with the upper 
pattern transitioning to deep troughing across the northeast late 
week. This should bring a return to colder temperatures 
(around/slightly below normal) starting Thursday. Still quite a ways 
out, but we are watching the potential for a coastal system for 
Friday. There is large amount of spread among ensemble 
members/solutions in the track of the surface low pressure. A chunk 
of solutions favors a well offshore track; however, there are 
solutions that also show a track closer to shore which would yield a 
mix precip and/or snow depending on the temperatures/exact track. As 
we head into next week, deterministic/ensemble guidance should come 
into better agreement in the details. Just something to watch for 
now.

&&

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

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

TAF Update: 18z

Rest Today... High confidence

VFR through the afternoon. Rain begins to move in from SW to NE
tonight. Lower IFR/LIFR CIGS will lag behind the rain with dry 
low level air. Winds turn light easterly.

Tonight... High confidence

Moderate to heavy rain will help saturate the low levels between
02-04z tonight, allowing CIGS to turn IFR/LIFR. CIGS remain
IFR/LIFR overnight after the rain ends due to light ENE flow.
Rain ends between 06-08z tonight with showers lingering into
Sunday morning. Significant LLWS concerns for the Cape and
Islands tonight as 2kft winds approach 60 to 70 knots from the
SW while a steep low level inversion could keep surface winds 
under 20 knots from the SE.

Sunday... High confidence in trends, moderate confidence in
timing.

Winds turn WNW Sunday morning, but CIGS may be slow to improve
until Sunday afternoon when drier low level air begins to work
in behind the low. Rain showers and low CIGS will linger for 
the Cape and the Islands for much of the day.


KBOS Terminal... Moderate Confidence. 

VFR with winds shifting east this afternoon. Rain will reach the
terminal between 23-00z, however IFR/LIFR CIGS will lag behind
the rain due to low level dry air. Moderate rain should reach
the terminal around 03z along with the IFR/LIFR CIGS. CIGS
remain IFR/LIFR through mid Sunday morning with lingering
showers and drizzle. Only moderate confidence on when CIGS
improve on Sunday. Current expectation is CIGS wont improve until
late Sunday morning to early afternoon.

KBDL Terminal... Moderate Confidence.

VFR with light and variable winds this afternoon. Rain moves in
between 21-22z this evening. IFR CIGS will lag behind the rain 
until closer to 02z when moderate rain move in. Rain ends 
between 06-07z, however showers could linger until day break. 
CIGS improve to MVFR/VFR mid to late Sunday morning.


Outlook /Sunday Night through Wednesday/...

Sunday Night: VFR. Strong winds with gusts up to 45 kt. 

Monday: VFR. Strong winds with local gusts up to 40 kt. 

Monday Night through Tuesday: VFR. Breezy. 

Tuesday Night through 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.

Today through Sunday... High confidence. 

A quasi-stationary frontal boundary sits south of the islands this 
morning, but will shift north late morning into the afternoon. NE 
wind early, less than 10 knots, then E late afternoon 10 to 15 
knots, gusts 18 to 22 knots.  Rain becomes widespread from south to 
north, starting 2 PM to 4 PM across the southern waters and 6 PM to 
8 PM across the eastern waters. Rain ends early Sunday, wind shifts 
to the NNW then W by Sunday afternoon, with gusts 20 to 25 knots. 
Strong winds anticipated overnight, Gale Watch in effect for all 
waters Sunday night though Monday morning.

Outlook /Sunday Night through Wednesday/...

Sunday Night: Moderate risk for gale force winds with gusts up
to 45 kt. Rough seas up to 11 ft. Chance of rain, slight chance
of snow. 

Monday: Low risk for gale force winds with gusts up to 35 kt.
Areas of rough seas. 

Monday Night through Tuesday: Moderate risk for Small Craft
Advisory winds with gusts up to 25 kt. Local rough seas. 

Tuesday Night: Strong winds with areas of gusts up to 30 kt.
Areas of seas approaching 5 ft. Slight chance of rain showers. 

Wednesday: Moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Local rough seas. Slight chance of rain
showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...Winter Weather Advisory from 5 PM this afternoon to 10 AM EST 
     Sunday for MAZ002-004-008-009-026.
RI...None.
MARINE...Gale Watch from Sunday evening through Monday morning for 
     ANZ230>237-251.
     Gale Watch from Sunday evening through Monday afternoon for 
     ANZ250-254>256.

&&

$$

DISCUSSION...Dooley/Mensch
AVIATION...KP
MARINE...Dooley/Mensch