Lexington Weather

Lexington, Massachusetts, USA

54°F

4/12/2026 3:37pm

Lexington Conditions: Clear
Temperature: 54.3°F / 12.4°C
Dew Point: 27.3°F
Relative Humidity: 35%
Wind: Calm, 10-min avg: Calm, gust: 2 mph
Barometer: 30.35 in Falling Slowly
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 121853
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
253 PM EDT Sun Apr 12 2026

.WHAT HAS CHANGED...

Gale Watches have been upgraded to Gale Warnings Monday for 
Cape Cod/Buzzards Bays and Nantucket/Vineyard Sounds.

&&

.KEY MESSAGES...

- Dry weather through this afternoon with highs in the 50s. A 
  few showers tonight, mainly across northern MA. Gusty 
  southerly winds develop for Monday, especially across the Cape
  and Islands.

- Unseasonably warm, summer-like conditions are expected next 
  week with highs mainly in the 70s to low 80s, though 
  confidence is tempered by uncertainty in a possible backdoor 
  cold front; otherwise, mainly dry with only isolated showers 
  and a period of gusty winds Wednesday afternoon. 

&&

.DISCUSSION...

KEY MESSAGE 1...Dry weather through this afternoon with highs 
in the 50s. A few showers tonight, mainly across northern MA. 
Gusty southerly winds develop for Monday, especially across the 
Cape and Islands.

A large high pressure moves further offshore this afternoon, 
leaving southern New England dry through the rest of the evening
with increasing cloudiness and high temperatures in the low to 
mid 50s. 

Later tonight, a shortwave associated with a warm front pushes 
through the region, bringing increased chances for a few rain 
showers (mainly across northern MA). As the warm front 
approaches the region by daybreak Monday, a 45-55 knot 
southwesterly LLJ develops over the South Shore and Cape. This 
will bring a surge of warm air and gusty winds, leading to high 
temperatures ranging from the mid 50s over the Cape/Islands to 
upper 60s/low 70s further inland. Wind gusts increase to 30-40 
mph over the Cape/Islands... 25- 30 mph elsewhere.

KEY MESSAGE 2...Unseasonably warm, summer-like conditions are 
expected next week with highs mainly in the 70s to low 80s, 
though confidence is tempered by uncertainty in a possible 
backdoor cold front; otherwise, mainly dry with only isolated 
showers and a period of gusty winds Wednesday afternoon. 

Bottom line up front: a period of summer-like warmth is 
expected away from the immediate coast beginning Tuesday and 
lasting through the end of the workweek, as a strong subtropical
ridge develops over the Gulf. This will support southwest flow,
advecting higher moisture and temperatures into the Northeast. 
That said, there are forecast challenges that could lead to 
notable temperature busts, primarily tied to a potential 
backdoor cold front. Uncertainty remains regarding the placement
of the backdoor cold front. On Tuesday, it appears to be 
displaced north of southern New England. However, localized sea 
breezes may develop, resulting in onshore flow and keeping 
coastal communities noticeably cooler (upper 50s), while areas 
just inland warm into the 70s. Few spots in the Connecticut 
River Valley may approach 80F. By Wednesday, NAM12km places the 
backdoor cold front across northeastern Massachusetts. While not
taken as gospel, it highlights the potential for a sharp 
temperatures gradient across southern New England. Upper 40s to 
lower 50s at the tip of Cape Ann and Cape Cod versus lower 80s 
in the Connecticut River Valley. Ensembles guidance supports 
this uncertainty, with temperature spreads of 20-25 degrees, 
reflecting sensitivity to frontal placement and potential for 
forecast busts. Confidence should improve as higher-resolution 
guidance resolves this feature. For now, expect highs generally 
in the 70s through the week (and possible into the upcoming 
weekend) with a few days potentially reaching the lower 80s. 
Western areas will likely be the warmest, while eastern areas 
remain most susceptible to cooler marine air. Overnight lows 
will be mild, in the mid-50s to lower 60s. 

In terms of sensible weather, no significant synoptic systems 
are on the horizon for the coming week. However, with elevated 
PWATs, even weak forcing may be enough to generate a few 
isolated showers or a rumble of thunder at times, mainly Tuesday
night and again Wednesday afternoon into the evening, as weak 
surface lows and mid-level shortwaves traverse the periphery of 
the Gulf-centered ridge. No widespread or washout rainfall is 
expected. Additionally, Wednesday afternoon could become gusty 
from a low-level jet passage. Opt'd to increase wind/gusts with 
a blend of the NMB 90th percentile which bumped wind gusts 
across interior southern New England to 20-30 mph.

&&

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

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

High confidence.

Mainly VFR conditions continue through Monday. A few showers 
tonight mainly across northern MA may result in briefly lower 
conditions in some areas. Possible MVFR-IFR conditions in low 
clouds and fog patches developing near the south coast Monday 
afternoon as high dewpoint air begins to work over the 
relatively cold ocean. 

Southerly winds 6-12 kt this afternoon, but with localized sea 
breezes developing along parts of the immediate coast. SW winds 
will increase overnight tonight into Monday with gusts of 20 to 
30 kts expected in most areas, except up to 35 kts possible over
the Cape/Island terminals


KBOS Terminal... High confidence in TAF. Sea breeze should kick
out 23z-00z.

KBDL Terminal... High confidence in TAF.

Outlook /Tuesday through Friday/...

Tuesday through Tuesday Night: VFR. Slight chance SHRA.

Wednesday: VFR. Breezy. Slight chance SHRA.

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

Thursday through Friday: VFR. Slight chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Monday Night...High confidence.

Winds/seas increase to Small Craft Advisory thresholds tonight 
as a strengthening LLJ brings southwesterly wind gusts of 25 to 
30+ kt over all the waters. Buzzards/Cape Cod Bays and 
Nantucket/Vineyard Sounds could see some nearshore 35 kt gusts, 
which prompted upgrading Gale Watches to Warning for Monday. 
Will also likely see the development of fog across the southern 
waters on Monday as high dewpoint air advects northward over the
relatively cold ocean.

Outlook /Tuesday through Friday/...

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

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

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

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

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

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 2 AM to 8 PM EDT Monday for ANZ230-
     236.
     Gale Warning from 6 AM to 6 PM EDT Monday for ANZ231>234.
     Small Craft Advisory from 2 AM Monday to 5 AM EDT Tuesday for 
     ANZ235-237.
     Small Craft Advisory from 10 PM this evening to 2 AM EDT 
     Tuesday for ANZ250-251.
     Small Craft Advisory from 2 AM Monday to 8 AM EDT Tuesday for 
     ANZ254>256.

&&

$$

DISCUSSION...Dooley/McMinn
AVIATION...Dooley/McMinn
MARINE...McMinn