Lexington Weather

Lexington, Massachusetts, USA

30°F

12/7/2025 6:01am

Lexington Conditions: Few Clouds
Temperature: 29.8°F / -1.2°C
Dew Point: 25.3°F
Relative Humidity: 83%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.97 in Steady
Visibility: 10 miles
Snow Today: 0.0 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 070749
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
249 AM EST Sun Dec 7 2025

.SYNOPSIS...
Dry and cold today. An arctic front moves through overnight 
tonight into Monday morning with a low chance for brief 
scattered snow showers, primarily for northern MA. Well below 
normal temperatures Monday with an arctic airmass overhead. More
unsettled overall next week with a few systems moving through 
the region. This will bring periodic chances for rain/snow 
showers starting Tuesday night, continuing into Saturday. Very 
gradual warming trend into Tuesday with highs around normal 
Wednesday/Thursday.

&&

.NEAR TERM /THROUGH TODAY/...
Key Message:

* Mix of sun and clouds through the day

High pressure builds in for the start of the day ahead of a weak 
mid-level shortwave moving in from the west. Light winds prevail for 
much of the day with high pressure overhead, coming from mainly the 
NW for the first half of the day. Some brief clearing is expected in 
the mid morning hours before filling in through the afternoon ahead 
of the shortwave. Highs supported by 925 mb temperatures around 
-5C will likely be in the mid 30s for most, with low 40s for
 Cape Cod and the Islands. 

&&

.SHORT TERM /TONIGHT THROUGH 6 PM MONDAY/...
Key Messages:

* Low chance for scattered snow showers tonight

* Arctic air returns for Monday

Associated with the shortwave moving across the region late Sunday 
is a moisture-starved cold front. This will usher in another arctic 
airmass to start the week, with 925 mb temperatures tanking to 
between -11C and -15C late tonight into Monday morning. Lows tonight 
will dip back into the mid to upper teens for most and into the low 
20s for Cape Cod and the Islands.

Latest guidance has trended precipitation chances over southern New 
England down a bit and drier air aloft will aid in decreasing 
chances for spot snow shower or two. At most, a low chance for some 
snow showers lingers for northern MA.

NW winds pick up Sunday night into Monday post-front with good 
mixing, so gusts between 20-30 MPH are possible through much of 
Monday. The arctic airmass aloft remains over the region and high 
pressure builds back in briefly post-front. So, not much improvement 
from overnight temperatures is expected; 925 mb temperatures remain 
around -11C through the day, so highs in the 20s and 30s can be 
expected.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Key Messages: 

* Periodic chances for precipitation next week starting Tuesday 
  night, continuing through Saturday.  

* Uncertainty in pattern details (timing, amounts, precip type), 
  especially Wednesday onward. 

Details... 

Surface high pressure shifts into the region Monday night helping 
relax the pressure gradient. This will support decreasing winds; 
however, elevated winds may linger a bit longer over the waters 
overnight. Clear skies, light wind, and a well below normal airmass 
aloft will support temperatures dropping into the single digits and 
teens Monday night. Can't rule out a few higher elevation spots 
dropping a little below zero. 

There is a consensus among ensemble guidance for shift to an active 
pattern starting later Tuesday, continuing through next weekend. The 
pattern features the passage of several embedded disturbances in the 
flow aloft bringing periodic chances of rain/snow showers through 
the week. However, there is still uncertainty in the details 
including timing of showers and expected amounts, especially mid-
week onward. 

The first shot at showers comes Tuesday night. Ensembles show light 
amounts with scattered snow showers bringing mainly a trace to an 
inch, with the greatest chance at an inch or greater for the higher 
elevations of interior MA. For the south coast and Cape/Islands, 
rain/snow showers are possible. Another round or two of showers is 
likely sometime Wednesday into Thursday. Precip type will become 
more clear as we gain more details about the system track and 
timing. Temperatures lean warmer for Wednesday during the day. This 
would favor rain or rain/snow showers higher up. The cold front 
swings through Weds nigh which may bring another round of rain/snow 
showers with it.  

Some cold advection showers are possible later in the week. There is 
potential for yet another wave to move through Friday-Saturday. 
There is still plenty of uncertainty in the timing and track of the 
wave and low pressure which will influence the precipitation 
chances. Things will become more clear as we get closer. Something 
that is higher confidence is the arrival of colder air by the end of 
the weekend with below normal temperatures returning to the region.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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

06Z TAF Update: 

Through 12Z Today...High confidence. 

VFR. NW winds around 5 kt. Areas of stratus early this morning.
Confidence moderate for timing that the stratus scatters out, 
but more likely by 12Z. 

Today...High Confidence. 

VFR. NW winds 5-10 kts. After 18z, winds briefly may go VRB
before shifting to the S and SE/ESE for BOS. Winds continue to shift
toward the W/WSW after 00Z. Mid-level ceilings move in during 
the afternoon.

Tonight...High Confidence. 

VFR. Mid-level ceilings early tonight. Winds shifting toward WSW
after 00z 5-10 kts. Frontal passage overnight between 05-09Z. 
Slight chance of -SN for northern terminals. Probabilities too
low to include in TAF. 

Monday...High Confidence. 

VFR. Gusty NW winds with gusts 20-30 kts. Winds gradually
decreasing after 18Z. 

KBOS Terminal...High Confidence in TAF. 

KBDL Terminal...High Confidence in TAF. 

Outlook /Monday Night through Thursday/... 

Monday Night through Tuesday: VFR. Breezy. 

Tuesday Night: Mainly VFR, with local MVFR possible. Windy with
local gusts up to 30 kt. Slight chance RA, slight chance SN.

Wednesday: Mainly VFR, with local MVFR possible. Windy with
local gusts up to 30 kt. Chance RA, chance SN.

Wednesday Night: Mainly VFR, with local IFR possible. Breezy.
Chance RA.

Thursday: VFR. Breezy. 

&&

.MARINE...
Forecaster Confidence Levels...

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

Today through Monday...High confidence.

Tranquil boating conditions expected through today, with winds 
and seas below small craft advisory thresholds. Light S winds 
continue into most of today, then become NW tonight around 10-15
kt. Seas 3 ft or less all waters thru Sun.

Winds pick up post-front tonight into Mon and seas build to 5-7
ft over the outer waters through Mon. Gusts between 20-30 kt 
are possible across all waters Mon morning, with occasional 
gusts to 35 kt possible for the northern outer waters. Small
Craft Advisories have been issued for the waters starting at 06z
tonight, continuing through 06z Tue for the outer waters and
ending at 21z today for the coastal waters.

Outlook /Monday Night through Thursday/...

Monday Night: Winds less than 25 kt. Local rough seas. 

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

Tuesday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 30 kt. Areas of rough seas. Slight chance of
rain. 

Wednesday: Moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Areas of rough seas. Chance of rain. 

Wednesday Night: Strong winds with gusts up to 35 kt. Areas of
rough seas. Chance of rain. 

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

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 1 AM to 4 PM EST Monday for 
     ANZ231>235-237-251.
     Small Craft Advisory from 1 AM Monday to 1 AM EST Tuesday for 
     ANZ250-254>256.

&&

$$

SYNOPSIS...Hrencecin/Mensch
NEAR TERM...Hrencecin
SHORT TERM...Hrencecin
LONG TERM...Mensch
AVIATION...Hrencecin/Mensch
MARINE...Hrencecin/Mensch