Lexington Weather

Lexington, Massachusetts, USA

63°F

4/26/2025 7:45pm

Lexington Conditions: Overcast
Temperature: 63.0°F / 17.2°C
Dew Point: 61.5°F
Relative Humidity: 95%
Wind: SW Calm, 10-min avg: 1 mph, gust: 10 mph
Barometer: 29.61 in Steady
Visibility: 10 miles
Rain Today: 0.64 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 240614
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
214 AM EDT Thu Apr 24 2025

.SYNOPSIS...

Pleasant and dry today under high pressure, with the exception of a 
slight chance of showers this evening across northern Massachusetts. 
Unseasonably warm temperatures arrive Friday. Cooler with widespread 
rain showers Saturday ahead of our next system, drying out for 
Sunday. Cooler and breezy on Sunday, followed by continued dry 
weather through Wednesday and mild temperatures. A front arrives 
Wednesday with next chance of showers. 

&&

.NEAR TERM /THROUGH TONIGHT/...

* Warmer on Thursday with quiet and dry weather, save for the chance 
  of a spot shower in NW MA in the evening. 

A quiet and clear night continues with temperatures in the urban 
centers in the mid to upper 50s while some typically good radiative 
cooling spots in southeast MA are in the upper 30s at this hour. 
Even so, temperatures will rebound quickly with sunrise as a warm 
front lifts north through the region and brings with it high 
temperatures quite a bit warmer than yesterday for the interior of 
SNE, in the mid to upper 70s. The location with the best shot at 
seeing upper 70s will be in the CT Valley. Dry, under high pressure 
and largely zonal flow; the only exception is northwestern/north 
central MA, in closest proximity to a weak shortwave crossing 
northern New England tonight which may provide enough lift to kick 
off a few spot showers this evening. Tonight winds may become a bit 
breezy along the south coast with the warm frontal passage; this 
with increased cloudcover and warm advection will keep low 
temperatures quite mild overnight, in the 40s and 50s.

&&

.SHORT TERM /FRIDAY/...

* Dry, unseasonably warm. 

Friday will be much warmer than average as warm advection in the mid 
levels pushes 850 mb temps to 11C. BUFKIT soundings show a good 
mixing environment; can expect high temperatures in the upper 70s 
and even low 80s, warmest in the CT valley. Given onshore southerly 
flow, temperatures along the south coast will remain in the low to 
mid 60s. 

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...

Key Messages:

* The next chance for widespread rain comes in Saturday, but there 
  are uncertainties with the exact timing. 

* Drier conditions Sunday though is cooler with breezy NW winds. 

* Dry and warm for the first half of next week. 

Big Picture: High pressure shifts offshore late Friday, a northern 
stream trough moves in from the eastern Great Lakes. Developing low 
pressure system to the northwest with a modest LLJ (40-60 kt) over 
southern New England, helping to advect higher PWATs ~1.5", setting 
the stage for a soggy and breezy Saturday. Good news, should be able 
to salvage the second-half of the weekend, improvements Sunday, but 
will be cooler (seasonable) and breezy. High pressure and mid-level 
ridging will dry things out and aid in warming our temperatures for 
Monday and Tuesday, followed up by a possible cold front passage 
and showers for Wednesday. 

Friday Night through Sunday: Increasing clouds overnight with rain 
holding off, likely not arriving until Friday morning. These clouds 
help to keep nighttime lows mild in the lower and middle 50s. 
Southwesterly LLJ of 40-60 kt usher in moisture and PWATs increase to 
1.5", 2-3 standard deviations above normal. There is a marginal risk, 
at least 5% chance of rainfall exceeding flash flood guidance for 
all of southern New England. Global ensembles settling towards 0.50" 
to 0.75" for rainfall amounts. Prob rainfall greater than 1.0" have 
walked back over the past 24 hours, 30 to 40 percent the previous 24 
hours. And now is less than 20 percent. There are timing issues for 
the rain, as mentioned previously, GFS is biased towards a quicker 
arrival and departure, though continued to lean towards the slower 
solution, ECMWF/GEM, which would bring in the rain from west to east 
sometime between 8am and 12pm. Rain continues throughout the day, a 
few rumbles of thunder cannot be ruled out either due to limited 
instability. It will be quite windy on Saturday as a southerly LLJ 
of 45-55 knots develops over eastern MA and RI. With cold ocean 
waters still in the 40s, it will be tough to mix down much of that 
wind. Hence, gusts should stay in the 25-35mph range. High temps 
range from the low to upper 60s. System moves out late night into 
early Sunday morning, clearing from west to east as NW flow advects 
cooler and drier air into the region, may hold onto clouds or a spot 
shower across parts of eastern/central MA and RI on Sunday with the 
departure of the mid-level low. Much cooler Sunday, highs in the 50s 
with gusty NW winds 30-40 mph. 

Monday through Wednesday: Really nice period of weather, especially 
Monday and Tuesday, with high pressure and mid-level ridging. Will 
see temperatures rebound to the low and middle 70s on Monday and 
Tuesday is warmer in the middle to upper 70s, while at the coast 
it's cooler in the 60s. Frontal boundary arrives for Wednesday and 
depending on the

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

06Z TAF Update:

Through 12Z: High Confidence

VFR. Winds light and variable.

Today: High Confidence. 

VFR. Winds light and variable, becoming southerly 5-10 kts in
the afternoon. Expect haze and smoke to begin moving into CT 
during the afternoon which could cause some visibility 
obstruction. A few spot showers are possible in northern MA in
the evening. 

Tonight: High Confidence.

VFR. Primarily SSWly winds 5-10kts. Smoke/haze continues to 
spread into the rest of SNE with visibility obstruction 
possible.

Friday: High Confidence. 

VFR. Winds light and variable in the morning increasing to 5-10
kts out of the S/SW/SE in the afternoon. 
 
KBOS TAF...High confidence...

Sea breeze kicks in early today between 12-13z. Sea breeze 
kicks out in the late afternoon/evening, then winds aloft begin 
to increase, bringing some light wind shear Thursday evening. 
Smoke/haze could cause some visibility obstruction overnight 
Thursday into Friday morning.

KBDL TAF...High confidence in TAF. 

Light and variable winds tonight turning southerly tomorrow.
Smoke/haze could cause some visibility obstruction as early as
Thursday afternoon, possibly into Friday morning. 

Outlook /Friday Night through Monday/...

Friday Night: Mainly VFR, with local IFR possible. Breezy.
Chance SHRA.

Saturday: Mainly MVFR, with areas IFR possible. Breezy. SHRA,
isolated TSRA.

Saturday Night: Mainly VFR, with areas MVFR possible. Breezy.
Chance SHRA.

Sunday: VFR. Windy with local gusts up to 30 kt. 

Sunday Night: VFR. Breezy. 

Monday: VFR. 

&&

.MARINE...
Forecaster Confidence Levels:

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

Today...

High pressure to the south of the coastal waters will support 
another calm day with light northeast winds in the morning becoming 
steady out of the south during the afternoon from 10 to 15 knots. 
Seas remain 2 feet or less.

Tonight...

South/southwest winds up to 10 knots with seas building to 2-3 feet.

Friday...

High pressure overhead. Winds 10-15 kts, seas 2-3 ft.

Outlook /Friday Night through Monday/...

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

Saturday: Moderate risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Rain showers, isolated
thunderstorms. 

Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Chance of rain showers,
isolated thunderstorms. 

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

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

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

&&

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

&&

$$

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