Lexington, Massachusetts, USA
35.1°F
1.7°C
Cold
Clear
Overnight: Lo 53 °F
Sunday: Hi 82 °F
Dew Point:
32.4°F
Humidity: 90%
UV Index: 0.0 None
Barometer:
mb
Rain Rate: 0.00 in/hr
Rain Today: 0.01 in
Rain Saturday: 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 Sun Aug 16, 2026 1:48am EDT
- Seasonably warm with increasing humidity today. Sunshine this morning gives way to increasing clouds this afternoon ahead of an approaching system.
- Showers develop late tonight into Monday, though coverage and rainfall amounts have trended lower from previous forecasts.
- Warm temperatures and moderate humidity return through the middle of next week, followed by increasing shower chances late in the week.
Mostly Clear
Lo 53 °F
Mostly clear, with a low around 53. North wind around 3 mph.
Mostly Sunny
Hi 82 °F
Mostly sunny, with a high near 82. Southeast wind 2 to 6 mph.
Mostly Cloudy then Chance Rain Showers
Lo 65 °F
A chance of rain showers after 1am. Mostly cloudy, with a low around 65. South wind around 9 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.
Rain Showers Likely
Hi 75 °F
Rain showers likely and patchy fog. Cloudy, with a high near 75. Southeast wind 6 to 9 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
Slight Chance Rain Showers then Mostly Cloudy
Lo 66 °F
A slight chance of rain showers before 7pm, then patchy fog and a slight chance of rain showers between 7pm and midnight. Mostly cloudy, with a low around 66. North wind around 5 mph. Chance of precipitation is 20%.
Partly Sunny
Hi 81 °F
Partly sunny, with a high near 81. Northeast wind around 5 mph.
Partly Cloudy
Lo 63 °F
Partly cloudy, with a low around 63. South wind around 5 mph.
Sunny
Hi 85 °F
Sunny, with a high near 85. Southwest wind 2 to 7 mph.
Partly Cloudy
Lo 65 °F
Partly cloudy, with a low around 65. West wind around 6 mph.
Chance Rain Showers
Hi 82 °F
A chance of rain showers before 2pm, then a chance of showers and thunderstorms. Partly sunny, with a high near 82. Northwest wind around 6 mph. Chance of precipitation is 50%.
Chance Showers And T-Storms then Partly Cloudy
Lo 59 °F
A chance of showers and thunderstorms before 8pm. Partly cloudy, with a low around 59. Northwest wind around 5 mph. Chance of precipitation is 40%.
Sunny
Hi 80 °F
Sunny, with a high near 80. Northeast wind around 6 mph.
Slight Chance Rain Showers
Lo 59 °F
A slight chance of rain showers between 8pm and 2am. Partly cloudy, with a low around 59. South wind 2 to 6 mph.
Mostly Sunny then Slight Chance Rain Showers
Hi 79 °F
A slight chance of rain showers after 3pm. Mostly sunny, with a high near 79. Northeast wind 2 to 7 mph.
Issued by:
National Weather Service Boston / Norton, MA
Updated Sun Aug 16, 2026 1:48am EDT

N 3 mph
N 3 mph
N 3 mph
N 3 mph
N 3 mph
N 2 mph
NE 2 mph
E 2 mph
SE 3 mph
S 3 mph
SW 5 mph
SW 5 mph
S 6 mph
S 6 mph
SE 6 mph
S 7 mph
S 8 mph
S 9 mph
S 8 mph
S 8 mph
S 7 mph
S 7 mph
S 7 mph
S 7 mph
S 7 mph
S 8 mph
S 8 mph
S 8 mph
S 8 mph
S 8 mph
S 8 mph
S 9 mph
SE 9 mph
SE 9 mph
SE 8 mph
SE 8 mph
000
FXUS61 KBOX 160645
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
245 AM EDT Sun Aug 16 2026
.WHAT HAS CHANGED...
Rainfall coverage and amounts have trended lower for late tonight
into Monday.
&&
.KEY MESSAGES...
- Seasonably warm with increasing humidity today. Sunshine this
morning gives way to increasing clouds this afternoon ahead of
an approaching system.
- Showers develop late tonight into Monday, though coverage and
rainfall amounts have trended lower from previous forecasts.
- Warm temperatures and moderate humidity return through the
middle of next week, followed by increasing shower chances
late in the week.
&&
.DISCUSSION...
KEY MESSAGE 1...Seasonably warm with increasing humidity today.
Sunshine this morning gives way to increasing clouds this afternoon
ahead of an approaching system.
High pressure begins to shift offshore today as a developing low
pressure system moves across Quebec and another area of low pressure
develops across the Mid-Atlantic. Warm air advection aloft will
increase cloud cover through this afternoon, while temperatures
remain seasonable, ranging from the upper 70s to lower 80s. Humidity
gradually increases today, with dew points returning to the lower
60s and becoming more noticeable compared to Saturday. Most, if not
all, of the daylight hours remain dry, with showers arriving late
this evening into the overnight hours.
KEY MESSAGE 2...Showers develop late tonight into Monday, though
coverage and rainfall amounts have trended lower from previous
forecasts.
Over the past several nights, we have been monitoring the potential
for a more widespread rainfall event late tonight into Monday.
However, the trend continues toward less rainfall, particularly
across southern New England. The 00Z guidance generally depicts the
strongest forcing associated with a developing weak surface low
across the Mid-Atlantic and another area of low pressure near
northern New England and southern Quebec. With southern New England
positioned between these areas of stronger forcing, it may be
difficult to fully capitalize on the higher PWATs of 1.8 to 2.0
inches across the region.
Nevertheless, periodic showers will develop late tonight and
continue into Monday. There remains high confidence that most of
today remains dry. The majority of the 00Z CAMs keep southern New
England dry through roughly 8 PM, though a few solutions bring
showers into western portions of the region earlier. The most
favorable period for numerous light to moderate showers appears to
be after sunset through roughly 4 to 6 AM Monday.
The threat for heavy rainfall has also decreased. While an isolated
heavier downpour cannot be ruled out, widespread heavy rainfall is
no longer expected. Forecast rainfall totals have generally trended
to less than a half inch across Connecticut, Rhode Island, and
southeast Massachusetts, with amounts closer to a quarter inch or
less possible farther north across Massachusetts. Given this trend,
the Marginal Risk for Excessive Rainfall no longer includes southern
New England.
Showers should become more scattered during the day Monday,
potentially resulting in a drier, though cloudy and humid,
afternoon. A cold front then pushes through the region late Monday
and may initiate an isolated thunderstorm. However, extensive cloud
cover and limited instability should limit thunderstorm development
and intensity. Given the expected cloud cover, showers, and easterly
flow, Monday will be cooler, with highs ranging from the lower to
mid-70s across eastern Massachusetts and Rhode Island to around 80
degrees towards the Connecticut River Valley. Dew points remain
elevated, resulting in rather sticky conditions.
KEY MESSAGE 3...Seasonably warm temperatures and moderate humidity
return through the middle of next week, followed by increasing
shower chances late in the week.
Drier air advects in from the northwest late Monday night into
Tuesday, leading to another dry stretch Tuesday through Wednesday,
and possibly into the first half of Thursday, as surface high
pressure builds back into the region. Temperatures remain
seasonable, with highs in the lower to middle 80s and tolerable
humidity as dew points remain in the lower to middle 60s. Ensemble
guidance continues to signal a transition toward more unsettled
weather late in the week, with shower chances returning and
temperatures potentially trending slightly below normal.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Today...High confidence.
VFR. Light northerly winds early this morning become south-southwest
this afternoon at 8 to 12 kt. A sea breeze develops across eastern
coastal Massachusetts around 14Z, becoming east-southeast between 15-
17Z at 10 to 12 kt.
Tonight...High confidence in trends, moderate confidence in timing.
Ceilings lower to MVFR from west to east between 04Z and 08Z,
coinciding with the arrival of SHRA. There is a low probability of
TSRA overnight, but confidence is too low to include at this time.
Within areas of steadier rain, visibilities may lower to 2-4 SM;
otherwise, visibilities remain 6 SM or greater.
The sea breeze across eastern coastal Massachusetts shifts to south-
southwest around 00-02Z. Winds then gradually back to south-
southeast and southeast overnight at 10 to 15 kt, while interior
terminals remain below 10 kt.
Monday...Moderate confidence.
Periods of SHRA during the early morning hours, becoming more
scattered through the morning and afternoon as the steadier
precipitation shifts east. Cannot rule out an isolated TSRA during
the afternoon as a cold front approaches, though limited instability
should keep coverage sparse. IFR to MVFR ceilings are expected
during the morning, with gradual improvement during the afternoon.
Conditions may improve to MVFR, and potentially VFR, at some western
terminals by late afternoon, while lower ceilings may persist longer
across eastern Massachusetts and Rhode Island. Confidence remains
lower regarding the timing and extent of improvement. Southeast
winds early become east, then northeast during the afternoon,
eventually shifting to the north by 00Z Tuesday.
KBOS Terminal...High confidence.
VFR. Light northerly winds around 5 kt or less this morning shift to
the east with a sea breeze around 14Z, increasing to 6 to 10 kt.
Winds become east-southeast by 18Z at 10 to 12 kt. The sea breeze
ends with winds shifting south around 23Z. Dry through much of the
TAF period, with shower chances increasing after 06-09Z Monday as
ceilings lower to MVFR.
KBDL Terminal...High confidence.
Outlook /Monday Night through Thursday/...
Monday Night: Mainly VFR, with local IFR possible. Slight
chance SHRA.
Tuesday: Mainly VFR, with local MVFR possible.
Tuesday Night through Wednesday: VFR.
Wednesday Night: VFR. Slight chance SHRA.
Thursday: VFR. Chance SHRA, slight chance TSRA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through Monday...High confidence.
High pressure shifts east of the coastal waters today ahead of a low
pressure system arriving tonight into Monday. Southerly winds today
increase to around 20 kt tonight, then shift to southeast Monday
morning and east by late afternoon, with gusts of 20 to 25 kt. Seas
remain relatively calm today under high pressure but build to 5 to 8
ft by early Monday morning as the low approaches. Small Craft
Advisories remain in effect through Monday night.
The risk for rip currents increases Monday along south-facing
beaches, then Tuesday along east-facing beaches, as rough seas and
long-period swells settle in behind the departing system.
Outlook /Monday Night through Thursday/...
Monday Night: Winds less than 25 kt. Seas up to 5 ft. Chance of
rain showers.
Tuesday: Winds less than 25 kt. Seas up to 5 ft.
Tuesday Night: Winds less than 25 kt. Seas locally approaching
5 ft.
Wednesday through Wednesday Night: Winds less than 25 kt.
Thursday: Winds less than 25 kt. Chance of rain showers, slight
chance of thunderstorms.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 8 AM to 11 PM EDT Monday for ANZ231-
232-250-251-254.
Small Craft Advisory from 2 AM Monday to 2 AM EDT Tuesday for
ANZ233>235-237-255-256.
&&
$$
DISCUSSION...Dooley
AVIATION...Dooley
MARINE...Dooley
Radar images courtesy Weather Underground / Intellicast.
UV Index forecast high for today: 7 High
Current (Measured): 0.0 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:
0.01 in
Rain Today:
0.00 in
Saturday:
0.01 in
August:
1.26 in
2026
1:17pm
36.1°F
High today:
12:00am
25.2°F
Low today:
2:28pm
30.4°F
High Saturday:
7:11am
16.2°F
Low Saturday:
12:00am
25.2°F
Low wind chill today:
7:11am
16.2°F
Low wind chill Saturday:
1:17pm
33.3°F
High dew pt today:
11:56pm
20.7°F
High dew pt Saturday:
None
Wind gust today:
None
Wind gust Saturday:
No alerts/warnings active for Southeast Middlesex County.
First Light:
6:11am
Sunrise:
6:39am
Sunset:
5:19pm
Twilight ends:
5:47pm
Daylight length:
10 hours 39 minutes
Phase:
Waxing Crescent (82%)
Moon set:
8:18am
Moon rise:
9:38pm