Lexington Weather

Lexington, Massachusetts, USA

63°F

4/26/2025 8:07pm

Lexington Conditions: Overcast
Temperature: 63.0°F / 17.2°C
Dew Point: 61.5°F
Relative Humidity: 95%
Wind: SW 3 mph, 10-min avg: 2 mph, gust: 8 mph
Barometer: 29.62 in Steady
Visibility: 10 miles
Rain Today: 0.64 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 211816
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
216 PM EDT Mon Apr 21 2025

.SYNOPSIS...
High pressure will bring dry conditions with less wind today.
Scattered showers return tonight into early Tuesday as a warm 
front moves through. Dry conditions with above normal
temperatures expected Tuesday afternoon into Friday. A frontal
system may bring more showers Friday night into Saturday, then
drying out next Sunday as this system moves offshore.

&&

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

* Dry and mild today with sea-breezes developing

High pressure moves offshore today. Light N to NW winds 
gradually become Light S to SE winds by late morning. Dry
weather expected through most of today. Near normal 
high temperatures along both immediate coasts, with above normal
highs across the interior. Increasing clouds this afternoon. Low 
risk for very late day spotty showers across far NW
Massachusetts.

&&

.SHORT TERM /TUESDAY/...
Key Messages:

* Scattered showers developing tonight then moving offshore
  Tuesday
* Well above normal high temperatures expected Tuesday

High pressure over the North Atlantic continues to move farther
offshore tonight. A low pressure moving into the Great Lakes
should first push a warm front across our region, which will
provide the first chance for showers. While there is some
elevated instability, am thinking the forcing is too weak to
support thunderstorms past sunset. These showers could linger 
across the Cape and islands after daybreak Tuesday, while drier 
weather is anticipated elsewhere.

This will be followed by the weakening cold front of this
system. Thus, expecting southern New England to remain in more 
of a warm sector environment Tuesday. Once the sunshine breaks 
out, there should be a rather significant warm up, at least away
from the Cape and islands. Still contending with water
temperatures in the mid 40s there.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Key Messages:

* Mainly dry Wednesday and Thursday with temperatures slightly 
  above normal. 

* Pattern becomes more unsettled Friday through the weekend with 
  periodic chances for precipitation. 

Tuesday Night through Weekend: 

A cold front moves through Tuesday night into early Wednesday
morning. Wednesday trends slightly cooler than Tuesday, although 
still warmer than normal overall. Highs range in the 50s for the
Cape/Island and 60s for the interior. Light NW winds expected
under broad high pressure with localized sea breezes in the
afternoon for the coastal areas. 

A similar pattern stays in place through the end of the week
with zonal flow and 850mb temperature anomalies signaling at
slightly above normal temperatures. Ensemble guidance shows a
transition to a more unsettled pattern Friday into the weekend.
Heights fall across the region ahead of an upper level trough 
moving over the Great Lakes. A weaker leading shortwave moves 
through Friday evening with the main trough moving through by 
the end of the weekend. This will bring a few rounds of 
precipitation. Still need to iron out the details with the 
timing/chances of the first wave of showers on Friday. A more 
consistent round of rain moves in overnight through Saturday. 
Temperatures range around normal. Conditions gradually dry out 
Sunday.

&&

.AVIATION /18Z MONDAY THROUGH FRIDAY/...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

18z TAF Update:

Through 00z Tuesday: High confidence. 

VFR. S winds around 7-12 kt, with seabreezes continuing at BOS 
until about 22-23z.

Tonight: High confidence. 

VFR thru at least 04z Tue. Categories then start to deteriorate
to MVFR from 04-08z from W to E, in 4-6 SM -SHRA and ceilings 
010-020. Outside chance at IFR ceilings but think chances for
IFR are decreasing. -SHRA should be ongoing from ORH east by end
of this period, while trending dry for BAF/BDL. S winds around
10 kt, with areas of low level shear as SW jet of 40 kt moves
overhead.

Tuesday: High confidence in trends but moderate on timing. 

Sub-VFR ceilings (mainly MVFR/IFR range) early to scatter out 
to VFR 13-15z. It may take longer for south-coastal/Cape 
airports to scatter out to VFR and showed MVFR-IFR ceilings thru
at least 18z before trending to VFR. SW winds around 5-10 kt
then shift to WSW/W around 10 kt, with occasional gusts to 20 kt
for the interior.

Tuesday Night: High confidence.

VFR. WNW winds around 5-10 kt.
 
KBOS TAF...High confidence in TAF. Winds to shift to a 150-160
direction by 22z before turning southerly by 00z. VFR thru 07z,
then categories trend to MVFR with light showers. Improvement to
VFR anticipated by 13z. 

KBDL TAF...High confidence in TAF. VFR thru 04z, then 
categories trend to MVFR with light showers. Improvement to VFR 
anticipated by 11z. 

Outlook /Tuesday Night through Friday/...

Tuesday Night: VFR. Breezy. 

Wednesday through Thursday Night: VFR. 

Friday: VFR. Slight chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels:

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

Through Tuesday...High Confidence.

Rather tranquil boating conditions across the waters today and
tonight. Increasing S to SW winds Tuesday ahead of a dissipating 
cold front approaching the waters. This could lead to marginally
rough seas across portions of the southern outer coastal waters. 
Risk for some showers with reduced visibility after midnight.
These showers are expected to move east of the waters by Tuesday 
afternoon, but could leave some patch fog in their wake.

Outlook /Tuesday Night through Friday/...

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

Wednesday through Thursday Night: Winds less than 25 kt. 

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

&&

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

&&

$$

SYNOPSIS...Belk/Mensch
NEAR TERM...Belk
SHORT TERM...Belk
LONG TERM...Mensch
AVIATION...Belk/Loconto/Mensch
MARINE...Loconto/McMinn