Hourly Weather | Today › Friday, November 13, 2026
Active Weather Warnings
San Mateo, California
8 AM
Cloudy Weather
61°
Feels Like 55°
34
Humidity: 82%
UV Index: 0
Wind: 17 mph
9 AM
Cloudy Weather
63°
Feels Like 55°
39
Humidity: 91%
UV Index: 0
Wind: 20 mph
10 AM
Cloudy Weather
63°
Feels Like 57°
49
Humidity: 87%
UV Index: 1
Wind: 22 mph
11 AM
Rainy Weather
64°
Feels Like 55°
58
Humidity: 82%
UV Index: 1
Wind: 20 mph
12 PM
Rainy Weather
64°
Feels Like 55°
58
Humidity: 79%
UV Index: 1
Wind: 21 mph
1 PM
Rainy Weather
63°
Feels Like 54°
78
Humidity: 81%
UV Index: 1
Wind: 24 mph
2 PM
Rainy Weather
63°
Feels Like 54°
78
Humidity: 78%
UV Index: 1
Wind: 22 mph
3 PM
Rainy Weather
63°
Feels Like 54°
78
Humidity: 75%
UV Index: 0
Wind: 21 mph
4 PM
Rainy Weather
63°
Feels Like 54°
86
Humidity: 75%
UV Index: 0
Wind: 21 mph
5 PM
Rainy Weather
61°
Feels Like 52°
86
Humidity: 76%
UV Index: 0
Wind: 17 mph
6 PM
Rainy Weather
59°
Feels Like 50°
86
Humidity: 78%
UV Index: 0
Wind: 15 mph
7 PM
Cloudy Weather
59°
Feels Like 54°
40
Humidity: 76%
UV Index: 0
Wind: 13 mph
8 PM
Cloudy Night
57°
Feels Like 54°
34
Humidity: 77%
UV Index: 0
Wind: 9 mph
9 PM
Cloudy Night
57°
Feels Like 55°
37
Humidity: 80%
UV Index: 0
Wind: 7 mph
10 PM
Cloudy Night
55°
Feels Like 54°
47
Humidity: 82%
UV Index: 0
Wind: 6 mph
11 PM
Rainy Night
55°
Feels Like 52°
51
Humidity: 84%
UV Index: 0
Wind: 6 mph

Hourly Air Quality Forecast - AQI (US EPA)

8 AM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.27 µg/m³
  • PM10: 4.55 µg/m³
  • O3: 0.046 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

9 AM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.24 µg/m³
  • PM10: 4.03 µg/m³
  • O3: 0.046 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

10 AM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.29 µg/m³
  • PM10: 3.86 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 AM
45 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.36 µg/m³
  • PM10: 3.59 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

12 PM
46 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.52 µg/m³
  • PM10: 3.47 µg/m³
  • O3: 0.050 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.10 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

1 PM
45 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.73 µg/m³
  • PM10: 3.36 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.3 ppb
  • SO2: 0.1 ppb
  • CO: 0.10 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

2 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.27 µg/m³
  • PM10: 4.27 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

3 PM
45 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.6 µg/m³
  • PM10: 5.71 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

4 PM
46 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.43 µg/m³
  • PM10: 6.25 µg/m³
  • O3: 0.050 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

5 PM
45 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 2.02 µg/m³
  • PM10: 5.82 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

6 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.65 µg/m³
  • PM10: 5.08 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

7 PM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.42 µg/m³
  • PM10: 4.55 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

8 PM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.32 µg/m³
  • PM10: 4.26 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

9 PM
43 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.3 µg/m³
  • PM10: 4.15 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

10 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.28 µg/m³
  • PM10: 3.94 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 PM
44 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.23 µg/m³
  • PM10: 3.67 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.11 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Weather Alerts and Warnings for San Mateo

Minor Expected Likely

Coastal Flood Advisory

Coastal Flood Advisory issued November 13 at 3:44AM PST until November 13 at 4:00PM PST by NWS San Francisco CA
Nov 13, 3:44 AM → Nov 13, 4:00 PM
WHAT: Up to 1.5 ft of inundation above ground level is
possible in low-lying areas near shorelines and tidal
waterways.

WHERE: North Bay Interior Valleys and San Francisco Bay
Shoreline.

WHEN: Until 4 PM PST today.

IMPACTS: High tides will result in flooding of low-lying
infrastructure, isolated road closures, and coastal erosion.
Rising tides will bring water and waves farther up the beach
than normal, restricting escape from beaches and coastal areas.

ADDITIONAL DETAILS: At the San Francisco tide gauge, high tide
is expected to be: 1.5 ft above normal (7.3 ft MLLW) at 12:49 PM
today 11/13. These predictions include up to 1.8 ft of surge
that will enhance the astronomical tide and flooding threat.
High tide varies up to 90 minutes earlier or later along the
Pacific Coast and through the San Francisco Bay, respectively.
+ Read More
If travel is required, allow extra time as some roads may be closed. Do not drive around barricades or through water of unknown depth. Take the necessary actions to protect flood-prone property.
Updated: Nov 13, 6:54 AM Source: NWS Alert