Lexington Weather

Lexington, Massachusetts, USA

67°F

7/10/2025 12:31am

Lexington Conditions: Overcast
Temperature: 67.1°F / 19.5°C
Dew Point: 64.9°F
Relative Humidity: 93%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.94 in Steady
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 051747
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
147 PM EDT Sat Jul 5 2025

.SYNOPSIS...
Tranquil weather with low humidity continues today. Very warm 
temperatures in the upper 80s to lower 90s and rising humidity 
levels will lead to high heat indices Sunday and Monday. Unsettled 
weather makes a return Monday night, off and on through much of the 
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Messages...

* Dry today with more sun than clouds. 

Mid level height rises will lead to dry weather as surface high 
pressure begins to sink to our south. This placement directs light 
SW winds into SNE, though WAA doesn't kick in in earnest until 
Sunday when a trough of low pressure passes in closer proximity. A 
weak warm front in the mid levels will lead to increasing high 
clouds during the day, but there will be more sun than clouds, 
helping push high temperatures up into the mid 80s (lower on the 
south coast where onshore flow keeps temps in check). Tonight partly 
cloudy skies should keep radiational cooling from being as much of 
an issue as Friday night, keeping lows about 10 degrees warmer (in 
the mid 60s).

&&

.SHORT TERM /SUNDAY/...
Key Messages...

* Hotter with increasing humidity. 

The mid level ridge axis crosses New England on Sunday placing us 
beneath increasingly breezy SW flow. Warm air and and moisture is 
advected north pumping up both the heat and humidity. So, while it 
will be breezier, gusting 20 to 30 mph, it will feel much hotter 
than Saturday. Dewpoints increase from the 50s to the upper 60s 
while high temperatures make it back into the 90s; highest 
temperatures will be in the CT and Merrimack valleys while the 
coolest spots are on the south coast, thanks again to onshore flow.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Key Messages...

* Peak of the heat and humidity Monday. 

* Periodic chances of unsettled weather late Monday through the 
  week. 

Steering flow becomes rather zonal to start the week keeping warm SW 
flow around. While no rain is expected during the day, what will be 
notable is the 70F+ dewpoints that will make it feel very humid 
outside. A weak shortwave moving through the steering flow around 
Tuesday with a surface frontal system will bring more clouds heading 
into Tuesday along with the chance for scattered showers and 
thunderstorms. It remains difficult to nail down when these periodic 
bouts of unsettled weather move through, but another trough looks to 
move through around Thu/Fri. Temperatures are more seasonable after 
Monday.

&&

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

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

18z TAF Update: 

This Afternoon...High confidence. 

VFR. SW-SSW winds 8 to 12 knots. Sea breeze for south coast
(PVD). Low chance for a sea breeze to develop at BOS this
afternoon. 

Tonight...High confidence.

VFR. Any sea breezes turn back SSW early evening. SSW winds 5-10
kts. Less than 8 kts for the interior. Low level moisture may lead
to a FEW or SCT group of IFR clouds across southern RI and SE 
MA overnight. 

Sunday...High confidence. 

VFR. SSW to SW winds 10 to 15 knots with gusts 20 to 25 knots
developing by early afternoon.


KBOS Terminal...Moderate confidence in TAF. Sea breeze
potential. 

VFR. Potential for a sea breeze is looking less likely this 
afternoon given better mixed SW winds. 

KBDL Terminal...High confidence in TAF. 

Outlook /Sunday Night through Thursday/... 

Sunday Night: VFR. Breezy. 

Monday: VFR. Breezy. Slight chance SHRA.

Monday Night: VFR. Breezy. Chance SHRA, slight chance TSRA.

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

Tuesday Night: Mainly VFR, with local IFR possible. Chance
SHRA, slight chance TSRA.

Wednesday: VFR. Slight chance SHRA, slight chance TSRA.

Wednesday Night: VFR. Slight chance SHRA.

Thursday: Slight chance SHRA, slight chance TSRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Sunday: High confidence. 

Tranquil boating weather conditions through Saturday night. SW winds 
around 10-15 kt today and tonight. Seas 4 ft or less all waters, and 
around 1-2 ft nearshore. No obstructions to visibility expected. SW 
winds increase on Sunday, gusting 20-25 kts, as high as 30 kts on 
eastern waters. 

Outlook /Sunday Night through Thursday/...

Sunday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Seas locally approaching 5 ft. 

Monday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. 

Monday Night through Tuesday Night: Winds less than 25 kt.
Chance of rain showers, slight chance of thunderstorms. 

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

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

Thursday: Winds less than 25 kt. Slight chance of rain showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory from 7 AM Sunday to 8 PM EDT Monday for 
     CTZ002>004.
MA...Heat Advisory from 7 AM Sunday to 8 PM EDT Monday for 
     MAZ003>007-010>019-026.
RI...Heat Advisory from 7 AM Sunday to 8 PM EDT Monday for 
     RIZ001>004.
MARINE...None.

&&

$$

SYNOPSIS...BW
NEAR TERM...BW
SHORT TERM...BW
LONG TERM...BW
AVIATION...Dooley/Mensch
MARINE...BW