Lexington Weather

Lexington, Massachusetts, USA

46°F

4/19/2026 7:01am

Lexington Conditions: Mist, Overcast
Temperature: 45.9°F / 7.7°C
Dew Point: 44.4°F
Relative Humidity: 95%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.76 in Steady
Visibility: 3 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 141711
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
111 PM EDT Tue Apr 14 2026

.WHAT HAS CHANGED...
No significant changes, the forecast remains on track.

&&

.KEY MESSAGES...

- Summerlike warmth Today and Wednesday away from the coast, with 
  scattered late day/early evening thunderstorms and a low risk of 
  severe weather.

- Backdoor front may bring cooler temperatures Thu-Sat, especially
  in eastern MA, but uncertainty is high in exactly where it ends up.

- More seasonable temperatures early next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Summerlike warmth Today and Wednesday away from the 
coast, with scattered thunderstorms & a low risk of severe weather. 

Confidence remains high in summerlike warmth Today and Wednesday 
away from both coasts, as strong subtropical ridge builds over the 
region from the Gulf. All hi res guid has highs both days easily 
reaching the upper 70s to lower 80s inland (+18C to +20C at 925 
mph). Any early morning fog will burn off rapidly. Meanwhile, a weak 
pressure gradient supports cooling seabreezes for the immediate 
coastal areas, with temps dropping into the 50s to around 60. 
However, locations such as Boston and eastern MA, late morning/early 
afternoon seabreeze may give way to a warmer wind shift to the SSW 
after 18z/19z, as low level southwest jet traverses the region. This 
would yield a late day high temp, after 4/5pm.  

We continue to monitor the potential for severe storms during late 
afternoon and evening both Tue and Wed, mainly 2 PM to 10 PM 
(highest probs 4-8pm). Low amplitude s/wvs moving through the 
westerly flow, only yielding weak forcing for ascent, which is 
evident by the lack of height falls from each of these s/wvs. 
However, modest mixed layer CAPE up to 1000 j/kg, modest mid level 
lapse rates around 6.5C/KM and 0-6km shear up to 45 kt, providing 
sufficient instability and shear to compensate for the lack of 
strong forcing. This is reflective by hi res guid offering 2-5km 
updraft helocity tracks into western-central MA/CT, along with 
highest probabilities of lightning. Convection will weaken as it 
traverses eastward into RI and eastern MA. Not expecting a 
widespread severe weather, but can't rule out a few isolates storms 
that approach severe in western-central CT/MA. Given the shear and 
instability, along with steep low level lapse rates, strong to 
damaging winds will be the main threat.  

As previous forecaster noted, atmosphere still looks favorable for 
thunderstorms on Wed, although the high-res models don't show much 
in way of activity. Severe risk is lower on CSU and SPC HREF with 
axis shifted farther south into CT/RI and south of the Mass Pike. 
While overall severe threat remains low, we can't rule out a few 
storms capable of producing localized wind damage or hail. 

KEY MESSAGE 2...Backdoor front may bring cooler temperatures Thu-
Sat, especially in eastern MA, but uncertainty is high in exactly 
where is ends up.

Temp forecast becomes more uncertain later this week, as short wave 
energy riding up and over the top of the subtropical ridge, may be 
strong enough to lower heights and have a backdoor front enter SNE, 
especially northeast MA. However, at this time range, low 
predictability regarding the amplitude of individual short waves 
and attending surface boundaries/backdoor fronts. Thus, certainly 
potential for big temperature busts this far out in time.

Showers and thunderstorms could be more widespread Friday, as multi 
model guidance suggest a more robust mid level short wave moving 
across the Northeast into New England. 

KEY MESSAGE 3...More seasonable temperatures early next week.

As expected, difficult to sustain temps 20+ degs warmer than normal 
in April, thus good multi model agreement (especially at this time 
range) that a strong cold front is expected to cross region sometime 
Sun, accompanied by some showers, that could spill into early 
Monday. Much cooler airmass follows behind front early next week, 
with temperatures returning to more typical levels for mid April, 
generally in 50s to around 60.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

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

This Afternoon and Tonight...Moderate confidence in areal coverage 
of TSRA and timing. 

VFR. A cold front brings hit-and-miss thunderstorms to areas across 
western New England late this afternoon into the early evening. This 
could lead to brief MVFR ceilings and IFR visibilities. It bank of 
low stratus/fog develops off the east coast of MA, which should 
remain off shore the first half of the night, before inching on 
shore early Wednesday morning, here flight categories fall to MVFR. 

SW to S wind today, periodically gusty 15-20 knots. Wind speeds ease 
overnight, becoming calm in protected areas. 

Wednesday and Wednesday Night... Moderate Confidence.

Becoming VFR. A frontal boundary remains in the vicinity of SNE and 
have moderate confidence this remains across NE MA. North of the 
boundary MVFR with winds E to E. South of the boundary VFR and winds 
are SW. Showers and thunderstorms develop along the boundary between 
18z-00z. Overnight becoming IFR to MVFR across most of the region, 
the only area that could remain low-end VFR is be the lower CT River 
Valley and points SW. Light southwest wind. 

KBOS Terminal... Moderate confidence in TAF.

Have moderate confidence in the chance of TSRA and lower clouds 
Wednesday morning. Will have LLWS tonight between 02z-08z.

KBDL Terminal... Moderate confidence in TAF. 

Have moderate confidence in the timing and coverage of TSRA this 
afternoon/evening. 

Outlook /Wednesday Night through Sunday/...

Wednesday Night through Thursday: VFR. Chance SHRA, slight
chance TSRA.

Thursday Night through Friday Night: VFR. Chance SHRA.

Saturday: Mainly VFR, with local MVFR possible.

&&

.MARINE...
Forecaster Confidence Levels...

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

220 AM update...

High confidence through the end of the week, except across the 
northern MA waters, where uncertainty is high regarding the timing 
and position of backdoor front Wednesday through the end of the 
week. 

SCA remains in effect for leftover rough seas. Weak pressure 
gradient will support subsiding seas along with developing 
seabreezes near shore beginning late Tue morning. Only other issues 
will be late night/early morning fog and possible late day/evening 
brief isolated shower/thunderstorm. 

Outlook /Wednesday Night through Sunday/...

Wednesday Night: Winds less than 25 kt. Seas locally
approaching 5 ft. Chance of rain showers, slight chance of
thunderstorms. 

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

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

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

Saturday: Winds less than 25 kt.

&&

.CLIMATE...
Upcoming record highs:

Tue 4/14
Boston 83 in 2023
Hartford 96 in 2023
Providence 87 in 2023
Worcester 90 in 2023

Wed 4/15
Boston 82 in 1896
Hartford 88 in 1941
Providence 82 in 1938
Worcester 85 in 1941

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for 
     ANZ254>256.

&&

$$

DISCUSSION...Nocera
AVIATION...KJC/Loconto/Dooley
MARINE...Nocera
CLIMATE...Nocera