Lexington Weather

Lexington, Massachusetts, USA

83°F

5/27/2026 2:56pm

Lexington Conditions: Clear
Temperature: 83.1°F / 28.4°C
Dew Point: 60.8°F
Feels Like: 83.5°F
Relative Humidity: 47%
Wind: Calm, 10-min avg: Calm, gust: 7 mph
Barometer: 29.64 in Falling Slowly
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 271800
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
200 PM EDT Wed May 27 2026

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

&&

.KEY MESSAGES...

- A few showers and possibly a thunderstorm through early
  evening, mainly south of the MA Pike to the south coast.

- Cooler Thursday with scattered showers developing in the
  afternoon, especially across eastern MA.

- Broad cyclonic flow over northeastern North America will
  support unsettled weather in southern New England Friday
  through the middle of next week

&&

.DISCUSSION...
KEY MESSAGE 1...A few showers and possibly a thunderstorm 
through early evening, mainly south of the MA Pike to the south
coast.

Cold front will be moving south across SNE this afternoon 
reaching the south coast this evening. Weak instability develops
ahead of the front with MLCAPES 250-500 J/Kg. Instability is 
weak but low level convergence with the front may be enough for 
isolated low topped convection to develop later this afternoon 
and evening, mainly south of the MA Pike. The 3km NAM and NSSL- 
WRF are most aggressive with scattered storms developing while 
HRRR, WRF-ARW and RRFS show little to no convection. One of the 
main limiting factors is dry air in the mid levels which will 
serve to suppress stronger updrafts from developing, especially 
given just weak instability. So while we can't rule out a few 
showers or a t-storm developing, coverage should be limited. Any
convection will end this evening as the front pushes south of 
the coast. This will also clear out any stratus and fog that 
develops over the Islands through this evening.

KEY MESSAGE 2...Cooler Thursday with scattered showers 
developing in the afternoon, especially across eastern MA.
 
Cooler temps Thu in the post-frontal airmass as 925 mb temps 
drop to 12-13C. Expect highs in the low-mid 70s, but likely 
holding in the upper 60s along the eastern MA coast due to a NE 
wind. A mid level shortwave rotates southward across the region 
with an accompanying increase in moisture. Guidance is bullish 
on scattered showers developing in the afternoon, especially 
across eastern MA into RI as a coastal front sets up across 
eastern MA along with a weak wave on the front which will 
enhance convergence. The showwers will wind down Thu evening as 
the shortwave moves to the east followed by subsidence. 

KEY MESSAGE 3...Broad cyclonic flow over northeastern North 
America will support unsettled weather in southern New England 
Friday through the middle of next week

A broad upper-level trough roughly centered over eastern North 
America/western North Atlantic Ocean will dominate the weather 
pattern in southern New England between Friday and the middle of 
next week. Several pulses of short-wave energy embedded in this 
broad clyclonic flow will bring a pro-longed period of largely 
unsettled weather. 

AThe first pulse of short-wave energy digs through The Northeast 
late Friday into Saturday bringing rounds of scattered precipitation 
mailny to eastern MA and NH/ME. As this system exits southeast by 
Saturday evening, we'll be left with somewhat seasonable conditions 
for Sunday with a mix of sun and clouds.

Beyond Sunday we begin to see more spread in the global model 
guidance. The consensus is for broad cyclonic flow to persist over 
The Northeast with additional precpitation chances on Monday and 
Tuesday. How long the cylonic upper-level flow meanders over The 
Northeast is uncertain with some ensemble solutions supporting more 
significant height rises by Wedensday and others supporting a later 
departure by late next week. Temperature will be slightly below 
normal during this stretch with daily highs/lows in the upper 
60s/low 70s and 40s/50s between Saturday and Wednesday.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Forecaster Confidence Levels...

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

18Z TAF Update:

Through 00z..

Mainly VFR. IFR stratus/fog expected to develop at ACK 20-22z 
but timing is not certain. Isolated showers and perhaps a 
t-storm developing south of the MA Pike after 20z. W wind gusts 
to 20 kt becoming NW, but SW winds near the south coast. 

Tonight...High Confidence.

IFR stratus and fog over the Islands clearing out and becoming
VFR toward 06z. VFR elsewhere. NW wind 5-10 kt becoming N.

Thursday...High Confidence.

VFR. Scattered showers developing in the afternoon, especially
eastern MA/RI with mainly VFR cigs. NW wind 10-20 kt interior
and N-NE around 10 kt near the eastern MA coast. 

Thursday night...High confidence. 

VFR. Light N-NW wind. 

KBOS...High confidence in TAF.

KBDL...High confidence in TAF. Low risk for a brief shower after
20z.

Outlook /Friday through Monday/...

Friday: VFR. Chance SHRA.

Friday Night through Saturday: Mainly VFR, with local MVFR
possible. Breezy. Chance SHRA.

Saturday Night: VFR. Breezy. Slight chance SHRA.

Sunday: VFR. Breezy. 

Sunday Night: VFR. Slight chance SHRA.

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

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Thursday night...

Winds and seas below SCA thresholds. SW-W winds up to 20 kt will 
shift to NW then N tonight. N-NE wind 5-15 kt Thu becoming N-NW Thu 
night. A few showers or a t-storm may develop over the south coastal 
waters through early evening. Scattered showers developing Thu 
afternoon. 

Outlook /Friday through Monday/...

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

Friday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers. 

Saturday: Moderate risk for Small Craft Advisory winds with
gusts up to 25 kt. Seas up to 5 ft. Chance of rain showers. 

Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Slight chance of rain
showers. 

Sunday: Winds less than 25 kt. Seas up to 5 ft. 

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

&&

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

&&

$$

DISCUSSION...KJC/RM
AVIATION...KJC/RM
MARINE...KJC/RM