Lexington Weather

Lexington, Massachusetts, USA

63°F

4/26/2025 7:26pm

Lexington Conditions: Overcast
Temperature: 63.0°F / 17.2°C
Dew Point: 61.5°F
Relative Humidity: 95%
Wind: SW 2 mph, 10-min avg: 2 mph, gust: 8 mph
Barometer: 29.61 in Steady
Visibility: 10 miles
Rain Today: 0.64 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 251512
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
1112 AM EDT Fri Apr 25 2025

.SYNOPSIS...
Unseasonably warm temperatures are expected away from the coast 
today, with a few areas reaching to around 80 degrees. Cloud cover 
increases tonight. Cooler with widespread rain showers and some 
thunderstorms Saturday ahead of our next system. Drier conditions 
Sunday, though a spot shower cannot be ruled out with a departing 
mid-level low. Will be much cooler and breezy. Dry and warm Monday 
and Tuesday. A frontal passage on Wednesday with showers and then 
drying out Thursday.

&&

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

* Dry and unseasonably warm. 

A stalled quasi-linear frontal boundary continues to create a few 
returns on radar across SNE early this morning but nothing is making 
it to the surface and these will continue to diminish. The main 
story for today will be the much above average temperatures as warm 
advection continues to push 850 mb temps closer to 10-11C. Even with 
more mid and upper level moisture today compared to yesterday which 
will lead to a mix of clouds and sun, should see high temperatures 
climbing into the upper 70s (even low 80s in the CT valley). The 
exception will be along the coasts where sea breezes will keep temps 
in the 60s and low 70s. A few spotty showers are possible over far 
northern MA in proximity to a lingering frontal boundary, but more 
likely that these stay to our north.

&&

.SHORT TERM /SATURDAY/...
Key Messages...

* Increasing clouds early Friday evening, with rains developing 
  overnight. Mild with lows in the 50s, perhaps a few areas staying 
  above 60 degrees.

* Widespread rainfall expected Saturday. 

Cloud cover lowers and thickens Friday evening into the overnight 
hours ahead of a northern stream trough moving through the Great 
Lakes with a surface frontal system out ahead of it. An 
isentropically forced precipitation shield will overspread SNE ahead 
of this system, arriving from west to east between 11pm and 5am. 
Forcing for ascent will be bolstered by a developing 35-45 kt 850 mb 
LLJ acting on a moisture plume with PWATs on the order of 1.5 
inches. This is 200+% above normal. The best moisture and the core 
of the jet is overhead Saturday morning, so this is when the 
steadiest rain is expected with some embedded downpours possible; 
dewpoints in the 60s will contribute to MUCAPE values of up to 500 
J/kg so in addition to some heavier downpours, embedded thunder is 
possible. A dry slot moves overhead late morning/afternoon so likely 
we'll see an end to the widespread rain in the middle of the day, 
followed by a quick line of showers and thunderstorms in the late 
afternoon/evening along and ahead of the cold front as it swings 
through. Temperatures ahead of the front will reach into the 60s. 
The core of the jet is overhead in the morning, when forecast 
soundings indicate a stout inversion should keep the strongest gusts 
aloft. So, though it will be breezy everywhere, the stronger gusts 
to 30-35 kts should be limited mainly to the Cape and islands.

&&

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

* Drier conditions Sunday, though a spot shower cannot be ruled out 
  with a departing mid-level low. Will be much cooler and breezy. 

* Dry and warm Monday and Tuesday. A frontal passage on Wednesday 
  with showers and then drying out Thursday. 

Saturday Night and Sunday: Few showers and isolated thunderstorms 
continue overnight, much of the rain ends before dawn. A mid-level 
low moves across New England on Sunday and will promote a few areas 
of rain, not a washout by any means, but likely more in the way
of clouds than sunshine... especially eastern-half of 
Massachusetts and Rhode Island. As the system moves across the 
region will promote CAA and gusty NW winds, nothing that raises 
to a level of an advisory, but gusts 25 to 35 MPH are possible. 
That will make the day feel even cooler. CAA aloft and mixing to
850mb will result in afternoon temperatures in the low and 
middle 50s. Clearing skies Sunday night and breezy conditions 
continue, lows fall into the middle 40s. 

Monday and Tuesday: Surface high pressure and mid-level ridging will 
bring dry and warm conditions to kickoff early next week. No weather 
concerns during this timeframe, will have above normal temperatures 
as well with daytime highs on Monday in the upper 60s at the coast 
and inland highs reach the middle 70s. Should trend even warmer for 
Tuesday with temperatures reaching the upper 70s. Monday night has 
the potential to be on the cooler side due to radiational cooling so 
lows are in the upper 30s to low 40s across interior southern New 
England and mid-40s at the coastal plain. Tuesday night is mild in 
the upper 50s to 60F degrees. 

Wednesday and Thursday:

The next shot at precipitation comes on Wednesday with the 
passage of a cold front, with perhaps thunder. If the frontal 
passage is later in the day, should have a good chance of having
highs return to the upper 70s. Drying out on Thursday with 
brief high pressure returning and cooler temperatures, albeit 
seasonable, in the mid-60s.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

15Z TAF Update:

Today: High confidence overall, though some uncertainty on
exactly when seabreeze develops.

VFR, although warm-frontal showers trail from BED-BOS and while
these will be lifting NE through 17z, this may disrupt the
timing of the eastern MA seabreeze until ~16-17z. Sub-VFR
ceilings may develop near the offshore southern waters/perhaps
ACK but better chance this arrives in by 00z. Away from the
coasts, south winds increase to around 10 kt.

Tonight: Moderate confidence. 

Generally VFR through late evening, though categories
deteriorate to MVFR-LIFR with steady rain developing towards
daybreak. Fog develops along south coast ahead of the rain. 

Saturday: Moderate confidence. 

IFR at all terminals through 16Z, slowly improving to MVFR and
VFR from west to east through the afternoon and evening as
widespread rain and scattered thunderstorms come to an end. A
final line of showers and storms is possible in the evening but
confidence on details is low. 
 
KBOS TAF...High confidence in TAF. VFR through at least 07z.
Seabreezes likely to be delayed until around 16-17z as ongoing
VFR type -SHRA lifts toward the NE.  

KBDL TAF...High confidence in TAF. VFR with south winds around 
10 kt.

Outlook /Saturday Night through Tuesday/...

Saturday Night: Mainly VFR, with local MVFR possible. Windy
with local gusts up to 30 kt. Chance SHRA.

Sunday: Mainly VFR, with local MVFR possible. Windy with areas
of gusts up to 30 kt. Slight chance SHRA.

Sunday Night through Monday: VFR. Breezy. 

Monday Night: VFR. 

Tuesday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels:

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

Tranquil boating conditions for mariners through today, with 
southerly winds around 10-15 kt and seas 2-3 ft. Dry weather 
prevails. 

SW winds then increase this evening to around 20 kt, with seas 
rising to around 4 ft. SCA conditions develop Saturday with rain and 
reduced visibilities. 

Outlook /Saturday Night through Tuesday/...

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

Sunday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Seas up to 5 ft. Slight chance of rain showers. 

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

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

Monday Night: Winds less than 25 kt. 

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

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 8 AM Saturday to 8 AM EDT Sunday for 
     ANZ231>237-250-254>256.

&&

$$

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