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 060126
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
826 PM EST Mon Jan 5 2026

.WHAT HAS CHANGED...
No significant changes to the forecast. Biggest impact expected to 
be from freezing rain Tuesday night. Confidence is low for a brief 
period of patchy freezing drizzle over southeast MA/RI tonight.

&&

.KEY MESSAGES...

- Light snow accumulations, a coating to 2 inches, expected this 
afternoon into tonight. Could end as a period of freezing rain  for 
some. 

- Mixed precipitation expected Tuesday night into Wednesday
  morning. 

- Milder with rain later in the week but no flooding expected.

&&

.DISCUSSION...
Key Message 1...Light snow accumulations, a coating to 2 inches, 
expected this afternoon into tonight. Could end as a period of 
freezing rain  for some. 

Snow has already begun falling in western Massachusetts and 
Connecticut at this hour as a clipper low moves from west to east 
across the region. This precipitation shield (all snow given temps 
in the low to mid 20s) will slowly but surely spread east through 
the afternoon, reaching eastern MA by evening. Model soundings show 
a decent amount of dry air to overcome in the low levels before 
these radar returns start to be realized as snow at the surface, but 
once it does we'll see light steady snow continuing into the first 
half of the night, tapering off before sunrise. As it does, we 
continue to monitor the low probability for some light freezing 
drizzle as the DGZ dries out above subfreezing air at the surface. 
This would be patchy, with the best odds for an hour or two over 
portions of RI into southeast MA. Freezing drizzle on top of a layer 
of snow would lessen any impact as well. Overall, confidence is not 
high enough in a widespread occurrence to issue any headlines. When 
all is said and done, we expect 1-2 inches of snow north of the MA 
Pike with a coating to an inch south. 

Key Message 2...Mixed precipitation expected Tuesday night into 
Wednesday morning. 

Dry start to the day on Tuesday following precip wrapping up early. 
Then comes our next in a quick succession of storm systems, this one 
a mid level shortwave and surface low moving from the Great Lakes 
Tuesday evening to the Gulf of Maine by Wednesday mid morning. This 
system pulls some moisture north with is as PWATs rise to around 
0.8"; the more critical aspect is the warm nose of air that moves in 
around 800 mb. 850 mb temps climb to +2-3C while at the surface, 
warm SW flow raises surface temps above freezing for most locations 
north and west of the I-95 corridor. Locations outside of the 
Worcester Hills and Berkshires that start as freezing rain should 
transition to rain as those temps rise, while in the high elevations 
accretion of 0.1-0.2' is possible. This will make for slippery roads 
during the Wednesday morning commute in the higher elevations. Bulk 
of the precipitation then moves out by sunrise for most, mid morning 
for northeast MA.

KEY MESSAGE 3...Milder with rain later in the week but no flooding 
expected.

Confidence is increasing on pattern change to milder weather later 
this week as subtropical ridge builds off southeast U.S coast and 
northern stream short wave closes off as it digs into Great Lakes. 
This sets up milder and increasingly moist SW flow aloft with rain 
likely sometime in Friday to Saturday timeframe as low pressure 
tracks through eastern Great Lakes into southern Canada. At this 
point odds do not favor excessive rainfall as system is progressive 
and none of the moisture or wind anomalies are off the charts, but 
certainly we should see a soaking rainfall with around 0.50" of rain 
being favored in ensemble probabilities. Snowmelt will also add some 
runoff but right now ensemble river forecasts only show minor rises 
at most and all well below bankfull. 

Behind this system, airmass is not terribly cold, more in the way of 
seasonable temperatures for early next week.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
Forecaster Confidence Levels...

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

Through 12z... Moderate Confidence. 

Low-end VFR and MVFR ceilings, periodic SN will lead to MVFR 
visibility, 3SM to 5SM. Opt'd to handle this with TEMPO for the 
terminals with the best chance of snow. Any snow accumulation are 
minimal, less than an inch. Pocket of FZRA is possible between 04z-
07z for terminal in RI and SE MA. Otherwise, RA for the Cape and 
Islands. Winds are fairly light with variable wind direction. 

Today... High Confidence. 

Dry, VFR for most terminals, Cape Cod and the Islands terminals 
remain MVFR. Light E/NE wind 5 to 8 knots. 

Tonight... Moderate Confidence. 

IFR and LIFR ceilings with scattered to widespread RA and FZRA 
overspreads the region from west to east, between 00z and 05z. 
Cannot rule out a brief period of SN, for terminals along and north 
of Rt.2 in northern Massachusetts. Ice accretion possible at KBDL & 
KORH, less likely for KBOS & KPVD. As for Cape Cod and the Islands, 
expecting rain only. Winds are light and variable. 

Wednesday... Moderate Confidence. 

IFR, continued showers, best chance for remaining FZRA will be in 
northern MA, while areas south deal with RA. Drying from west to 
east between 15z-18z, along with slow improvements to ceilings. 
Winds are westerly, 10 to 15 knots, gusting 20 knots. 

KBOS Terminal... Moderate Confidence. 

MVFR, periodic snow showers between 04z-07z, minor accumulation of a 
few tenths of an inch. Dry conditions today, with rain arriving by 
early evening. Low chance of freezing rain Tuesday night, will need 
to be watched, but left out of TAF for now due to low confidence. 

KBDL Terminal... Moderate Confidence.

Few snow showers through 06z, minor accumulations possible. MVFR 
ceilings, becoming VFR by 12z. Dry for much of today, then a wintry 
mixture after 00z. Possible freezing rain, opt'd to include a PROB30 
for this threat. IFR to LIFR overnight into early Wednesday. 

Outlook /Wednesday Night through Saturday/...

Wednesday Night: VFR. Breezy. 

Thursday through Thursday Night: VFR. 

Friday: Mainly VFR, with local MVFR possible. Breezy. Chance
RA.

Friday Night through Saturday: MVFR/IFR conditions possible.
Breezy. RA likely.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Tuesday night...High Confidence.

Relatively light winds and seas expected during this time.
Reduced visibility at times in light snow tonight, which should
transition to rain across the southern coastal waters after
midnight. Dry conditions expected for Tuesday with rain moving
in Tuesday night.

Outlook /Wednesday through Saturday/...

Wednesday: Winds less than 25 kt. Local rough seas. Chance of
rain, patchy fog. 

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

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

Thursday Night: Winds less than 25 kt. 

Friday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Seas locally approaching 5 ft. Chance of rain. 

Friday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Local rough seas. Chance of rain. 

Saturday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Areas of rough seas. Rain likely.

&&

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

&&

$$

DISCUSSION...BW/JWD
AVIATION...Dooley
MARINE...BW/JWD