Lexington, Massachusetts, USA
45.3°F
7.4°C
Chilly
Clear
Overnight: Lo 43 °F
Wednesday: Hi 65 °F
Dew Point:
41.0°F
Humidity: 85%
Barometer:
mb
Rain Rate: 0.00 in/hr
Rain Today: 0.00 in
Rain Tuesday: 0.00 in
Visibility: 10 miles
Wind:
Now: Calm
Avg: Calm
Gusts: 0 mph
Issued by:
National Weather Service Boston / Norton, MA
Point Forecast Updated Wed May 13, 2026 12:35am EDT
- Widespread rainfall Thu into Fri, with 1-2\" possible in spots.
- Cool weather Friday, gives way to a pattern change this weekend into next week, accompanied by unseasonable warmth.
Mostly Cloudy
Lo 43 °F
Mostly cloudy, with a low around 43. Southwest wind around 2 mph.
Chance Rain Showers
Hi 65 °F
A chance of rain showers between 8am and 2pm. Mostly cloudy, with a high near 65. South wind 2 to 14 mph, with gusts as high as 26 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
Mostly Cloudy then Slight Chance Rain Showers
Lo 51 °F
A slight chance of rain showers after 5am. Mostly cloudy, with a low around 51. South wind 7 to 14 mph, with gusts as high as 26 mph. Chance of precipitation is 20%.
Rain Showers
Hi 63 °F
Rain showers before 2pm, then showers and thunderstorms. Mostly cloudy, with a high near 63. Southeast wind 7 to 10 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Showers And T-Storms
Lo 47 °F
Showers and thunderstorms before 7pm, then patchy fog and showers and thunderstorms. Cloudy, with a low around 47. Northeast wind around 7 mph. Chance of precipitation is 90%.
Rain Showers Likely
Hi 56 °F
Rain showers likely. Mostly cloudy, with a high near 56. Northeast wind around 8 mph. Chance of precipitation is 70%.
Partly Cloudy
Lo 48 °F
Partly cloudy, with a low around 48. Northwest wind around 6 mph.
Sunny
Hi 76 °F
Sunny, with a high near 76. Southwest wind 5 to 10 mph.
Mostly Clear
Lo 57 °F
Mostly clear, with a low around 57. Southwest wind 7 to 10 mph.
Sunny
Hi 81 °F
Sunny, with a high near 81. West wind 7 to 10 mph.
Partly Cloudy
Lo 55 °F
Partly cloudy, with a low around 55. Northwest wind 3 to 9 mph.
Mostly Sunny
Hi 77 °F
Mostly sunny, with a high near 77. East wind 3 to 8 mph.
Partly Cloudy then Slight Chance Rain Showers
Lo 56 °F
A slight chance of rain showers after 5am. Partly cloudy, with a low around 56. South wind 3 to 8 mph.
Mostly Sunny
Hi 85 °F
Mostly sunny, with a high near 85. Southwest wind 5 to 12 mph.
Issued by:
National Weather Service Boston / Norton, MA
Updated Wed May 13, 2026 12:35am EDT

SW 2 mph
S 2 mph
S 2 mph
S 3 mph
S 5 mph
S 6 mph
S 7 mph
S 9 mph
S 12 mph
S 13 mph
S 14 mph
S 14 mph
S 14 mph
S 14 mph
S 14 mph
S 13 mph
S 12 mph
S 12 mph
S 10 mph
S 9 mph
S 8 mph
S 7 mph
S 7 mph
S 7 mph
SE 7 mph
SE 7 mph
SE 7 mph
SE 8 mph
SE 8 mph
SE 9 mph
E 9 mph
E 10 mph
E 10 mph
E 9 mph
E 9 mph
E 9 mph
000
FXUS61 KBOX 130600
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
200 AM EDT Wed May 13 2026
.WHAT HAS CHANGED...
Increased probability for 1-2" of rainfall possible Thu into
Fri.
&&
.KEY MESSAGES...
- Widespread rainfall Thu into Fri, with 1-2" possible in spots.
- Cool weather Friday, gives way to a pattern change this
weekend into next week, accompanied by unseasonable warmth.
&&
.DISCUSSION...
KEY MESSAGE 1...Appreciable rainfall Thursday, lingering into Fri.
High amplitude pattern Thu and Fri, yields roughly a 48 hr period of
wet weather. This high amplitude pattern contributes to a slower
arrival time of the rainfall, with much of this afternoon and
evening dry across MA/RI/CT. Just expecting some warm frontal
showers this morning and mainly confined to CT and northern MA. It
will become breezy this afternoon and continuing into early this
evening, with south winds gusting up to 20-30 mph at times. Cloud
cover and southerly winds off the cool ocean will cap highs this
afternoon to the low to mid 60s, about 5 degs cooler than normal.
Potent short wave streaming across the Great Lakes Tue night, digs
southeast and evolves into a high amplitude vertically closed cool
season low Thu, that slowly tracks just south of New England Fri.
This yields deep layer Atlantic moisture advection into SNE, with
PWATs greater than 1 inch Thu and Thu evening, along with strong
synoptic scale forcing for ascent. This will result in widespread
rain Thu and Thu night, then transitioning to lighter rain/drizzle
Fri, as dry slot overspreads the region. Rain will be moderate to
heavy at times, given strength and persistence of low level S-SE jet
(possible upslope enhancement), combined with some elevated
instability. Widespread rainfall of 0.5-1.0 inches, however up to 2
inches possible per hi res guid, ensembles and AI models. However,
given rainfall will be spread out over 2 days, not expecting any
flooding, more of a beneficial rainfall, with typical nuisance
street/highway flooding possible.
KEY MESSAGE 2...Cool weather Friday, gives way to a pattern change
this weekend into next week, accompanied by unseasonable warmth.
Departing vertically closed low and associated cloud cover, spotty
light rain/drizzle (especially Fri AM) and cool NE flow (only +6C at
925 mb), likely keeps highs in the 50s across the area Fri, with
coolest temps in eastern MA. Normal high this time of year is 65-70.
Then over the weekend and into next week, a pattern change evolves
with the northern stream jet deamplifying and giving way to the
subtropical ridge emerging and building up along the east coast.
Ensembles indicate high probabilities for temps well into the
mid/upper 70s Saturday and continuing to warm into the low and mid
80s Sunday! Possibly not quite as warm Monday, especially in eastern
MA, if a backdoor cold front makes it this far south. Otherwise, the
unseasonably warm weather continues early next week and likely peaks
Tue, with highs possibly as warm as 85-90, as some guidance streams
+23C/+24C airmass at 925 mb across SNE! It will be relatively dry
airmass/low humidity, with dew pts in the 50s, possibly rising into
the low 60s briefly Tue.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
06Z TAF Update:
Today...High confidence.
VFR. Light rain showers possible 10z-16z across CT into northern MA.
Otherwise dry weather prevails. Light SW winds early this morning,
become south late morning and increase 15-20 kt this afternoon with
gusts up to 30 kt possible at times.
Tonight...high confidence.
VFR and dry this evening, then MVFR/IFR cigs after 04z from west to
east, although remaining mainly dry. As surface winds slacken,
marginal LLWS possible given modest low level SW jet of 40 kt.
Thursday...high confidence on trends but some uncertainty on exact
timing of details.
MVFR/IFR with periods of rain, moderate to heavy at times. 20-25%
probability of -TSRA in embedded heavier showers. Marginal LLWS
possible in the morning, as 40-45 kt low level S-SE jet moves across
the area, then offshore during the afternoon.
KBOS...High confidence.
KBDL...High confidence.
Outlook /Thursday Night through Sunday/...
Thursday Night: MVFR/IFR conditions possible. SHRA likely,
slight chance TSRA.
Friday: Mainly VFR, with areas IFR possible. SHRA likely.
Friday Night: VFR.
Saturday through Sunday: VFR. Breezy.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
2 AM update...
Today through Thursday...High confidence.
Strengthening low level SW jet moves across SNE today, with light SW
early this morning, becoming south and increasing to 20-25 kt this
afternoon, except 25-30 kt in gusts near shore. Hence, SCA remains
posted. Other than a spot morning shower across northern MA waters,
dry weather and good vsby prevail today. South winds slacken tonight
with mainly dry weather. Rough conditions Thu, with S-SE winds 20-25
kt in the morning, then slacken in the afternoon and become east as
low pressure tracks south of New England. This low will bring
widespread rain to region Thu, moderate to heavy at times with
reduced vsby.
Outlook /Thursday Night through Sunday/...
Thursday Night: Winds less than 25 kt. Areas of seas
approaching 5 ft. Rain showers likely, slight chance of
thunderstorms.
Friday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain
showers.
Friday Night: Winds less than 25 kt. Seas up to 5 ft.
Saturday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Seas up to 5 ft.
Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft.
Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 11 AM this morning to 11 PM EDT this
evening for ANZ230>237-250-251-254>256.
&&
$$
DISCUSSION...Nocera
AVIATION...KJC/Nocera
MARINE...Nocera
Radar images courtesy Weather Underground / Intellicast.
UV Index forecast high for today: 4 Medium
Current (Estimated): 0 None
Note: Rain measured automatically by weather station. Rain totals do not necessarily include melted frozen precipitation.
For more accurate, manually measured rain data, see the Local Precip Data page.
0.00 in
Rain Rate (/hr):
0.00 in
Rain Last 60 min:
0.00 in
Rain Today:
0.00 in
Tuesday:
0.68 in
May:
8.18 in
2026
51.1 in
Season Snow:
12:00am
47.5°F
High today:
2:41am
44.2°F
Low today:
3:54pm
63.0°F
High Tuesday:
2:41am
43.2°F
Low Tuesday:
2:41am
44.2°F
Low wind chill today:
2:41am
43.2°F
Low wind chill Tuesday:
4:11am
41.0°F
High dew pt today:
11:26pm
39.2°F
High dew pt Tuesday:
None
Wind gust today:
3:22pm
4 mph
Wind gust Tuesday:
No alerts/warnings active for Southeast Middlesex County.
First Light:
4:53am
Sunrise:
5:25am
Sunset:
7:58pm
Twilight ends:
8:30pm
Daylight length:
14 hours 33 minutes
Phase:
Waning Crescent (16%)
Moon rise:
3:17am
Moon set:
4:23pm