Hourly Weather | Tomorrow Wednesday, March 18, 2026
Active Weather Warnings
San Mateo, California
12 AM
Night
63°
Feels Like 63°
0
Humidity: 76%
UV Index: 0
Wind: 5 mph
1 AM
Night
61°
Feels Like 59°
0
Humidity: 80%
UV Index: 0
Wind: 5 mph
2 AM
Cloudy Night
59°
Feels Like 57°
0
Humidity: 82%
UV Index: 0
Wind: 5 mph
3 AM
Cloudy Night
57°
Feels Like 57°
0
Humidity: 82%
UV Index: 0
Wind: 5 mph
4 AM
Cloudy Night
57°
Feels Like 57°
0
Humidity: 82%
UV Index: 0
Wind: 4 mph
5 AM
Cloudy Night
57°
Feels Like 57°
0
Humidity: 82%
UV Index: 0
Wind: 4 mph
6 AM
Cloudy Night
57°
Feels Like 57°
0
Humidity: 83%
UV Index: 0
Wind: 4 mph
7 AM
Cloudy Night
55°
Feels Like 55°
0
Humidity: 90%
UV Index: 0
Wind: 4 mph
8 AM
Cloudy Weather
57°
Feels Like 61°
0
Humidity: 78%
UV Index: 1
Wind: 5 mph
9 AM
Cloudy Weather
63°
Feels Like 66°
0
Humidity: 73%
UV Index: 2
Wind: 5 mph
10 AM
Cloudy Weather
66°
Feels Like 70°
0
Humidity: 66%
UV Index: 3
Wind: 5 mph
11 AM
Cloudy Weather
72°
Feels Like 75°
0
Humidity: 57%
UV Index: 4
Wind: 6 mph
12 PM
Cloudy Weather
75°
Feels Like 81°
0
Humidity: 50%
UV Index: 5
Wind: 6 mph
1 PM
Cloudy Weather
79°
Feels Like 82°
0
Humidity: 45%
UV Index: 5
Wind: 7 mph
2 PM
Cloudy Weather
82°
Feels Like 84°
0
Humidity: 41%
UV Index: 5
Wind: 7 mph
3 PM
Sunny Weather
84°
Feels Like 88°
0
Humidity: 37%
UV Index: 4
Wind: 8 mph
4 PM
Sunny Weather
84°
Feels Like 84°
0
Humidity: 37%
UV Index: 3
Wind: 8 mph
5 PM
Cloudy Weather
82°
Feels Like 82°
0
Humidity: 39%
UV Index: 2
Wind: 9 mph
6 PM
Cloudy Weather
81°
Feels Like 79°
0
Humidity: 42%
UV Index: 1
Wind: 8 mph
7 PM
Cloudy Weather
77°
Feels Like 73°
0
Humidity: 47%
UV Index: 0
Wind: 8 mph
8 PM
Cloudy Night
73°
Feels Like 72°
0
Humidity: 53%
UV Index: 0
Wind: 7 mph
9 PM
Night
72°
Feels Like 68°
0
Humidity: 58%
UV Index: 0
Wind: 6 mph
10 PM
Night
70°
Feels Like 66°
0
Humidity: 63%
UV Index: 0
Wind: 5 mph
11 PM
Night
66°
Feels Like 64°
0
Humidity: 64%
UV Index: 0
Wind: 5 mph

Weather Alerts and Warnings for San Mateo

Moderate Expected Likely

Heat Advisory

Heat Advisory issued March 16 at 9:51PM PDT until March 20 at 8:00PM PDT by NWS San Francisco CA
Mar 16, 9:51 PM Mar 20, 8:00 PM
WHAT: High temperatures in the low to mid 90s across the interior
and 80s along the coastline.

WHERE: The Bay Area and Central Coast.

WHEN: Until 8 PM PDT Friday.

IMPACTS: This level of heat affects most individuals sensitive to
heat, especially those without effective cooling and/or adequate
hydration. Impacts possible in some health systems and in
heat-sensitive industries. Hot conditions can cause heat illnesses.

ADDITIONAL DETAILS: Much above normal temperatures in the upper
80s to mid 90s are expected this week across the Bay Area and
Central Coast. Portions of the interior Central Coast may reach the
upper 90s starting mid to late week. Overnight lows in the upper
50s to low 60s will offer some relief to the lower elevations but
will offer minimal relief within the higher elevations. Conditions
will be much above normal along the coast this week but coastal
residents may experience more relief overnight than those across
the interior. The risk of heat related illnesses will increase with
each additional day of heating from this event.
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Hydration is a critical piece to surviving the heat. Drink water, and if possible, take water to those who are vulnerable. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to the early morning or evening. Take action when you experience symptoms of heat exhaustion and/or heat stroke. Beat the heat and check the backseat! Do not leave young children or pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.
Updated: Mar 17, 2:24 AM Source: NWS Alert