Lexington Weather

Lexington, Massachusetts, USA

60°F

7/26/2026 11:38pm

Lexington Conditions: Clear
Temperature: 60.4°F / 15.8°C
Dew Point: 51.1°F
Relative Humidity: 71%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.81 in Steady
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 240740
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
340 AM EDT Fri Jul 24 2026

.WHAT HAS CHANGED...
No significant changes to the forecast.

&&

.KEY MESSAGES...

- Mainly dry conditions expected through the weekend with seasonable 
  temperatures. 

- Periodic chances for showers and thunderstorms late Monday
  through mid-week, potentially lingering into Thursday.

&&

.DISCUSSION...
KEY MESSAGE 1...Mainly dry conditions expected through the weekend
with seasonable temperatures.

Surface high pressure builds further over the region today with flow 
aloft becoming more zonal. High pressure overhead will result in 
light and generally variable wind patterns today allowing for local 
sea breezes in the coastal areas. Temperatures will be in seasonable 
ranges with highs in the low to mid 80s. Another clear night will 
support radiational cooler allowing temperatures to fall into the 
50s to around 60 overnight. 

The center of the surface high pushes offshore on Saturday shifting 
winds to the east. With weak high pressure still in place, expect 
another dry day with mainly sunny skies. Highs across the interior 
likely range in the low to mid 80s while the onshore flow will keep 
temperatures slightly cool (mid-upper 70s) along the immediate 
eastern coastal areas. By Sunday, mid-level troughing arrives from 
west. Most guidance also indicates a low pressure system passing 
offshore. As the NAM/RRFS are starting to come into range, they have 
been leaning more aggressive with bringing in a push of moisture 
from offshore later Sunday, particularly for the eastern portion of 
southern New England(Cape/Islands). Model soundings indicate a 
shallow layer of moisture in the lower levels supported by the 
easterly surface flow with drier mid-level air. This could 
potentially point to a layer of low clouds and even some patchy 
drizzle in areas of eastern MA developing through the day on Sunday. 
Other model guidance is less aggressive, but still shows a 
signal for moisture, although more faint. Due to the spread, 
this is lower confidence at this time. Details will become more 
clear as we sit more solidly in the high-res guidance window. 


KEY MESSAGE 2...Periodic chances for showers and thunderstorms
late Monday through mid-week, potentially lingering into
Thursday.

There is a good consensus across model guidance on a mid-level 
trough positioning across the region for a good through at least 
late-week next week. A series of shortwaves embedded in the flow are 
expected to progress across the region through the week supporting 
periodic chances for showers and thunderstorms. Flow becomes more 
southerly Monday with moisture gradually advecting into the region 
ahead of the first shortwave. By Tuesday, precipitable water 
values rise to 1.50 to 2". This will set up the region for 
periodic chances for showers and thunderstorms, especially in 
the late Monday through mid-week timeframe. There is potential 
for the unsettled conditions to linger through Thursday if the 
trough tracks slower. There is a fair amount of agreement among 
guidance that this won't be a complete wash-out with support for
more diurnally driven development of showers and thunderstorms 
in the afternoon/evenings. Given above normal precipitable water
amounts, localized heavy rainfall will be a possibility within 
any thunderstorms. There is a signal for potentially strong to
severe thunderstorms highlighted in the NSSL ML probabilities
Tue/Wed, given the higher instability and sufficient shear.
Sometimes to keep an eye on for now. Temperatures will likely 
hover between normal to just below normal for the first half of 
the week. 

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
Forecaster Confidence Levels...

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

06z TAF Update:

Today and Tonight...High Confidence.

VFR conditions today and tonight. Generally calm to light S 
winds for interior terminals. Diurnally driven sea breezes 
along the immediate coast starting ESE then shifting to SE/SSE
later in the after 8-12 kts. Sea breezes kick out 00-02Z
shifting winds back to light S/SSW. 

Saturday...High Confidence. 

VFR. Easterly winds for all terminals. Less than 10 kts for the
interior and 8-12 kts for the coastal areas. 

KBOS Terminal...High confidence in TAF. Sea breeze likely
develops 14-16Z and kicks back out to S/SSW 01-03Z. 

KBDL Terminal...High confidence in TAF.

Outlook /Saturday through Tuesday/...

Saturday through Saturday Night: VFR. 

Sunday: VFR. Slight chance SHRA.

Sunday Night through Monday: VFR. 

Monday Night: VFR. Slight chance SHRA.

Tuesday: Mainly VFR, with areas MVFR possible. Breezy. Chance
SHRA, chance TSRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Saturday...High confidence.

Light winds and seas 1-4 ft today and tonight. 

Moderate risk for rip currents over the weekend. 

Outlook /Saturday through Tuesday/...

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

Saturday Night through Sunday: Winds less than 25 kt. Areas of
seas approaching 5 ft. Slight chance of rain showers. 

Sunday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain showers. 

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

Monday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain showers. 

Tuesday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain
showers, slight chance of thunderstorms. 

&&

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

&&

$$

DISCUSSION...Mensch
AVIATION...Mensch
MARINE...Mensch