Lexington, Massachusetts, USA
35.1°F
1.7°C
Cold
Few Clouds
Today: Hi 96 °F
Tonight: Lo 76 °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 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 Jul 1, 2026 4:30am EDT
- Dangerous prolonged heat and humidity Wed through Sat with max afternoon heat indices in the 98 to 112 degree range with little relief at night. Peak of the heat Thu into Fri.
- A cluster of showers and a few thunderstorms may impact parts of our region very late today into tonight. Activity likely weakening with main severe weather risk to our northwest, but cannot rule out a low risk across western MA/CT.
- W/NW flow aloft may bring a low convective/severe weather risk Wed-Fri. However, limited forcing and cap may keep us mainly dry. Greatest risk for thunderstorms/severe weather potential might wait until Independence Day with the actual cold front.
Chance Showers And T-Storms
Hi 96 °F
A chance of showers and thunderstorms before 1pm, then a chance of showers and thunderstorms. Partly sunny, with a high near 96. Heat index values as high as 106. Southwest wind around 10 mph, with gusts as high as 22 mph. Chance of precipitation is 40%.
Chance Showers And T-Storms
Lo 76 °F
A chance of showers and thunderstorms before midnight, then a chance of showers and thunderstorms. Mostly cloudy, with a low around 76. Heat index values as high as 101. Southwest wind around 10 mph. Chance of precipitation is 40%.
Slight Chance Showers And T-Storms then Mostly Sunny
Hi 102 °F
A slight chance of showers and thunderstorms before 7am. Mostly sunny, with a high near 102. Heat index values as high as 111. West wind 8 to 13 mph. Chance of precipitation is 20%.
Mostly Clear
Lo 76 °F
Mostly clear, with a low around 76. Heat index values as high as 105. West wind 7 to 12 mph. Chance of precipitation is 20%.
Sunny
Hi 98 °F
Sunny, with a high near 98. West wind 7 to 13 mph.
Mostly Clear
Lo 73 °F
Mostly clear, with a low around 73. West wind 5 to 12 mph.
Sunny then Slight Chance Showers And T-Storms
Hi 95 °F
A slight chance of showers and thunderstorms after 3pm. Sunny, with a high near 95. West wind 5 to 9 mph.
Slight Chance Showers And T-Storms
Lo 70 °F
A slight chance of showers and thunderstorms before 4am. Partly cloudy, with a low around 70. Northwest wind 3 to 7 mph.
Partly Sunny then Chance Showers And T-Storms
Hi 88 °F
A slight chance of rain showers between noon and 2pm, then a chance of showers and thunderstorms. Partly sunny, with a high near 88. Northeast wind 3 to 7 mph. Chance of precipitation is 40%.
Chance Showers And T-Storms
Lo 66 °F
A chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South wind around 6 mph. Chance of precipitation is 50%.
Chance Rain Showers
Hi 83 °F
A chance of rain showers. Partly sunny, with a high near 83. East wind 3 to 8 mph. Chance of precipitation is 50%.
Chance Rain Showers
Lo 65 °F
A chance of rain showers. Mostly cloudy, with a low around 65. Northeast wind around 6 mph. Chance of precipitation is 50%.
Slight Chance Rain Showers
Hi 84 °F
A slight chance of rain showers. Mostly sunny, with a high near 84. Northeast wind 3 to 8 mph.
Partly Cloudy
Lo 63 °F
Partly cloudy, with a low around 63. South wind around 6 mph.
Issued by:
National Weather Service Boston / Norton, MA
Updated Wed Jul 1, 2026 12:57pm EDT

SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 10 mph
SW 9 mph
SW 9 mph
SW 8 mph
SW 8 mph
SW 8 mph
SW 8 mph
SW 8 mph
W 9 mph
W 9 mph
W 9 mph
W 9 mph
W 9 mph
W 9 mph
W 10 mph
W 10 mph
W 12 mph
W 12 mph
W 13 mph
W 12 mph
W 10 mph
W 9 mph
W 8 mph
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W 7 mph
W 7 mph
000
FXUS61 KBOX 011120
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
720 AM EDT Wed Jul 1 2026
.WHAT HAS CHANGED...
No significant changes to the forecast.
&&
.KEY MESSAGES...
- Dangerous prolonged heat and humidity Wed through Sat with max
afternoon heat indices in the 98 to 112 degree range with
little relief at night. Peak of the heat Thu into Fri.
- A cluster of showers and a few thunderstorms may impact parts
of our region very late today into tonight. Activity likely
weakening with main severe weather risk to our northwest, but
cannot rule out a low risk across western MA/CT.
- W/NW flow aloft may bring a low convective/severe weather risk
Wed-Fri. However, limited forcing and cap may keep us mainly
dry. Greatest risk for thunderstorms/severe weather potential
might wait until Independence Day with the actual cold front.
&&
.DISCUSSION...
KEY MESSAGE 1...Dangerous prolonged heat and humidity Wed
through Sat with max afternoon heat indices in the 98 to 112
degree range with little relief at night. Peak of the heat Thu
into Fri.
High confidence forecast in dangerous prolonged heat and humidity
Wed through Sat. Focused the headline messaging on the peak
threats rather than trying to slice the bologna too thin. Thus,
Extreme Heat Warnings for most of southern New England. Heat
Advisories for the Cape and Vineyard. The peak of this heat
looks to be in the Thursday-Friday time frame.
Heat indices will rise to between 98 and 108 degrees away from
the south coast. The worst of the heat and humidity will likely
be in the CT and Merrimack River valleys. High temperatures will
likely reach between 97 and 103 away from the south coast and
any very localized sea breezes. Heat indices will reach dangerous
levels in the 102 to 113 degree range. It will remain hot and
humid for Independence Day as well. While it may be a few degrees
lower than Thu/Fri, dangerous heat and humidity may continue and
will be determined by the timing of a cold front.
Not only will this be a dangerous prolonged period of heat,
there will be little relief at night. Low temperatures will only
drop into the middle 70s in most locations and 75 to 80 degrees
in the urban centers. In fact, Boston may not drop below 80
degrees during the peak of the heat and humidity!
KEY MESSAGE 2...A cluster of showers and a few thunderstorms may
impact parts of our region very late today into tonight. Activity
likely weakening with main severe weather risk to our northwest,
but cannot rule out a low risk across western MA/CT.
The other concern for late today and especially tonight is a
shortwave that will be dropping southeast in northwest flow aloft
around the developing ring of fire. Effective shear of 30-40 knots
is favorable for this activity to work into our region...but
instability will be rather marginal. So expect a cluster of
weakening scattered showers and perhaps a few thunderstorms to
impact portions of our region. The greatest risk is across western
MA/CT. The overall severe weather threat is low given the limited
instability in our region...but given northwest flow aloft and
lingering momentum can not rule out a low probability for some
severe weather in western MA/CT. However...currently thinking
greatest risk is northwest of our region.
KEY MESSAGE 3...W/NW flow aloft may bring a low convective/severe
weather risk Wed-Fri. However, limited forcing and cap may keep
us mainly dry. Greatest risk for thunderstorms/severe weather
potential might wait until Independence Day with the actual
cold front.
Anomalous heat and humidity will result in rather high instability
across our region Wed through Fri. In addition, a remnant EML
in northwest flow aloft is present. If somehow a few thunderstorms
do develop, they could quickly become severe, even during the
overnight/morning hours. However, a lack of overall synoptic
forcing and a mid level cap should keep this risk low. This
potential will still need to watched. Greatest risk for
convection and potentially some severe weather may wait until
Independence Day when a cold front and stronger forcing arrives.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
12z TAF Update...
Today through Thursday...High confidence outside of any potential
thunderstorms.
VFR conditions will dominate today through Thursday. Some minor
scattered shower activity may develop mid day around Boston. There
is the potential for a few strong thunderstorms especially this
afternoon and tonight. Timing/location of any thunderstorms
though remain rather uncertain and might be more of a nowcast
situation but look most plausible for western terminals. SW
winds will generally gust 15 to 20 knots later today and again
Thu...while parts of the Cape/Islands gust to 25 knots and
perhaps briefly around 30 knots in the typically prone spots.
KBOS Terminal...High confidence in TAF but will need to watch for a
few thunderstorms later today and tonight.
KBDL Terminal...High confidence in TAF but will need to watch for a
few more thunderstorms in the vicinity of the terminal later today
and tonight.
Outlook /Thursday Night through Sunday/...
Thursday Night through Friday: VFR. Breezy.
Friday Night: VFR.
Independence Day through Sunday: VFR. Slight chance SHRA,
slight chance TSRA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Today through Thursday...High confidence.
Bermuda high pressure will result in a persistent SW flow across our
waters. SW winds will gust to 25 knots at times today through
Thursday and long fetch will result in seas building to 3 to 6 feet
across our southern waters. Therefore...we have continued small
craft headlines for our southern waters into Thursday.
Outlook /Thursday Night through Sunday/...
Thursday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Seas up to 5 ft.
Friday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Friday Night: Winds less than 25 kt. Seas locally approaching
5 ft.
Independence Day: Winds less than 25 kt.
Saturday Night: Winds less than 25 kt. Slight chance of rain
showers, slight chance of thunderstorms.
Sunday: Winds less than 25 kt. Slight chance of rain showers.
&&
.CLIMATE...
Record High Temperatures:
July 1:
KBOS: 98/1872
KBDL: 101/1964
KPVD: 97/1964
KORH: 94/1913
July 2:
KBOS: 98/1963
KBDL: 99/1966
KPVD: 98/1941
KORH: 97/1901
July 3:
KBOS: 102/1911
KBDL: 102/1966
KPVD: 98/2002
KORH: 96/1911
July 4:
KBOS: 104/1911
KBDL: 99/1911
KPVD: 99/1919
KORH: 102/1911
Record High Minimum Temperatures:
July 1:
KBOS: 73/1958
KBDL: 73/1968
KPVD: 71/1968
KORH: 72/2018
July 2:
KBOS: 76/2002
KBDL: 73/2018
KPVD: 75/1941
KORH: 73/1963
July 3:
KBOS: 80/2002
KBDL: 73/2018
KPVD: 78/2002
KORH: 72/2002
July 4:
KBOS: 77/2002
KBDL: 74/2018
KPVD: 77/2002
KORH: 73/2018
July 5:
KBOS: 81/1999
KBDL: 77/1999
KPVD: 78/1999
KORH: 73/1999
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Extreme Heat Warning until 8 PM EDT Saturday for CTZ002>004.
Air Quality Alert from 11 AM this morning to 11 PM EDT this
evening for CTZ002>004.
MA...Extreme Heat Warning until 8 PM EDT Saturday for MAZ002>021-
026.
Heat Advisory until 8 PM EDT Saturday for MAZ022-023.
RI...Extreme Heat Warning until 8 PM EDT Saturday for RIZ001>007.
Air Quality Alert from 11 AM this morning to 11 PM EDT this
evening for RIZ001>008.
MARINE...Small Craft Advisory until 6 PM EDT Thursday for ANZ231>235-
237.
Small Craft Advisory until 11 PM EDT this evening for ANZ236.
Small Craft Advisory until 1 AM EDT Friday for ANZ254>256.
&&
$$
DISCUSSION...Frank
AVIATION...Frank/KS
MARINE...Frank
CLIMATE...FT
Radar images courtesy Weather Underground / Intellicast.
UV Index forecast high for today: 9 Very 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
Tuesday:
0.01 in
July:
1.26 in
2026
1:17pm
36.1°F
High today:
12:00am
25.2°F
Low today:
2:28pm
30.4°F
High Tuesday:
7:11am
16.2°F
Low Tuesday:
12:00am
25.2°F
Low wind chill today:
7:11am
16.2°F
Low wind chill Tuesday:
1:17pm
33.3°F
High dew pt today:
11:56pm
20.7°F
High dew pt Tuesday:
None
Wind gust today:
None
Wind gust Tuesday:
First Light:
6:11am
Sunrise:
6:39am
Sunset:
5:19pm
Twilight ends:
5:47pm
Daylight length:
10 hours 39 minutes
Phase:
Waning Gibbous (82%)
Moon set:
8:18am
Moon rise:
9:38pm