Lexington Weather

Lexington, Massachusetts, USA

38°F

4/12/2026 5:18am

Lexington Conditions: Clear
Temperature: 38.1°F / 3.4°C
Dew Point: 25.5°F
Relative Humidity: 60%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 30.39 in Steady
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 120730
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
330 AM EDT Sun Apr 12 2026

.WHAT HAS CHANGED...

Small craft advisories and gale watches issued for our coastal 
waters late tonight and Monday. Confidence continues to increase in 
well above normal summer-like warmth for much of the work week...at 
least away from the immediate coast. 

&&

.KEY MESSAGES...

- Dry weather today with highs in the 50s to near 60...but cooler 
  upper 40s to lower 50s on parts of the immediate coast. A few 
  showers tonight...mainly across northern MA. Gusty southerly winds 
  develop toward daybreak Mon.

- Summer-like warmth much of the work week with highs in the 70s
  and 80s at least away from the immediate coast. A few showers
  and thunderstorms are possible at times, but dry weather dominates.

&&

.DISCUSSION...

KEY MESSAGE 1...Dry weather today with highs in the 50s to near 
60...but cooler upper 40s to lower 50s on parts of the immediate 
coast. A few showers tonight...mainly across northern MA.
Gusty southerly winds develop toward daybreak Mon.

Large high pressure gradually shifts east of the region today. This 
will result in seasonable/pleasant weather to close out the 
weekend...But with much less wind than yesterday. Plenty of sunshine 
is also expected this morning...but we should see mid-high level 
cloudiness increase and thicken this afternoon out ahead of an 
approaching shortwave. High temperatures today will mainly be in the 
50s to perhaps near 60 in spots...but cooler upper 40s to the lower 
50s are expected along parts of the immediate coast with sea breezes.

A warm front and associated shortwave energy crosses the region 
tonight. The deeper moisture and stronger forcing will be located to 
our north across northern New England where the bulk of the showers 
will reside. Nonetheless...a few showers are expected tonight mainly 
across northern MA closer to the better forcing. Any rainfall 
amounts though should be rather light. Low temperatures will be in 
the 40s...but many locations will rise to around 50+ toward daybreak 
Mon as warm advection increases. In fact...a 45 to 55+ knot 
southwest LLJ will result in gusty southwest winds developing toward 
daybreak. 

KEY MESSAGE 2...Summer-like warmth much of the work week with highs 
in the 70s and 80s at least away from the immediate coast. A few 
showers and thunderstorms are possible at times, but dry weather 
dominates.

All of our model guidance continues to support well above normal 
temperatures for most of the work week. On Monday...strong warm 
advection aloft/southwest LLJ will result in a lot of clouds, gusty 
southwest winds and the risk for a few showers at times. High temps 
will mainly be in the 60s to the lower 70s...but cooler along the 
south coast given gusty southwest winds. 

The real warmth looks to arrive Tue and continue for the rest of the 
work week. A strong upper level ridge over the Gulf of Mexico will 
result in well above normal height fields across the region. This 
should yield high temps in the 70s and 80s for the rest of the work 
week...At least away from the immediate coast. We will have to watch 
for a backdoor cold front lurking to our north. Most of the guidance 
keeps it generally north of us during the work week except for areas 
near the eastern MA coast...where temps could be noticeably cooler 
for a day or two than the rest of the region. We also should mention 
that sometimes these backdoor cold fronts end up further south than 
the global guidance suggests...so this will be one potential fly in 
the ointment. Again right now thinking outside the immediate 
coast...odds favor summerlike warmth for the rest of the week. But 
given our climatology...still a bit cautious until we get into more 
of the high resolution CAMs which handle these situations better.

While much of the upcoming week will be dry...there will be the risk 
for a few showers/t-storms at times. Westerly flow aloft coupled 
with an anomalous airmass in place will result in this potential 
especially during the afternoon/evening hours. That being 
said...timing of any shortwaves in westerly flow aloft is often 
difficult. Just something to keep in mind. FWIW...the CSU machine 
learning probs do even has some low severe probs across the region 
on Tue. 

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...

Forecaster Confidence Levels...

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

06z TAF Update...High confidence.

Mainly VFR conditions continue today through Monday. A few showers 
tonight mainly across northern MA may result in briefly 
lower/localized conditions. We also should see MVFR-IFR conditions 
in low clouds and fog patches develop near the south coast during 
the day Monday as high dewpoint air begins to work over the 
relatively cold ocean. 

Light and variable winds early this morning become S at 6-12 knots 
this afternoon...but with localized sea breezes developing along 
parts of the immediate coast. SW winds will increase very late 
tonight and especially Monday with gusts of 20 to 30 knots 
expected...strongest of which will be near the south coast. In 
fact...we may see southwest wind gusts near 35 knots in the vicinity 
of KFMH given pattern recognition. 

KBOS Terminal... High confidence in TAF. Sea breeze should develop 
by 14z this morning. 

KBDL Terminal... High confidence in TAF.

Outlook /Monday Night through Thursday/...

Monday Night: VFR. Breezy. 

Tuesday through Tuesday Night: VFR. Breezy. Scattered SHRA.

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

Thursday: VFR. Chance SHRA.

&&

.MARINE...

Forecaster Confidence Levels...

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

Today through Monday...High confidence.

Winds/seas will remain below small craft advisory thresholds today. 
However...a strengthening LLJ very late tonight and especially 
Monday will result in SW wind gusts of 25 to 30+ knots over all the 
waters and potentially some nearshore 35 knot gusts in the 
climatologically favorable locations in this setup near 
Buzzards/Cape Cod Bays as well as Block Island and Nantucket sounds. 
Therefore...we opted to issue a Gale Watch for those waters on 
Monday. Lastly...will need to watch for the development of fog 
across the southern waters on Monday as high dewpoint air advects 
northward over the relatively cold ocean.

Outlook /Monday Night through Thursday/...

Monday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Areas of rough seas. Slight chance of rain
showers. 

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

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

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

Wednesday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft. Chance of rain showers. 

Thursday: Winds less than 25 kt. Areas of seas approaching
5 ft. 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 Watch from Monday morning through Monday afternoon 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...Frank
AVIATION...Frank
MARINE...Frank