Hourly Weather Forecast for Hayward, California

Hourly Weather | Today › Tuesday, September 8, 2026

Active Weather Warnings

Heat Advisory
Coastal Flood Advisory

Hayward, California

3 PM

91°

Feels Like 93°

Humidity: 27%

UV Index: 5

Wind: 8 mph

4 PM

91°

Feels Like 91°

Humidity: 25%

UV Index: 4

Wind: 9 mph

5 PM

90°

Feels Like 88°

Humidity: 27%

UV Index: 2

Wind: 9 mph

6 PM

88°

Feels Like 86°

Humidity: 29%

UV Index: 1

Wind: 9 mph

7 PM

84°

Feels Like 81°

Humidity: 34%

UV Index: 0

Wind: 8 mph

8 PM

81°

Feels Like 79°

Humidity: 40%

UV Index: 0

Wind: 6 mph

9 PM

77°

Feels Like 75°

Humidity: 46%

UV Index: 0

Wind: 6 mph

10 PM

73°

Feels Like 72°

Humidity: 51%

UV Index: 0

Wind: 4 mph

11 PM

72°

Feels Like 70°

Humidity: 56%

UV Index: 0

Wind: 2 mph

Hourly Air Quality Forecast - AQI (US EPA)

3 PM

46 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 9.51 µg/m³
PM₁₀: 19.31 µg/m³
O₃: 0.049 ppm
NO₂: 0.4 ppb
SO₂: 0.5 ppb
CO: 0.16 ppm

Health Recommendations:

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

4 PM

47 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 9.57 µg/m³
PM₁₀: 19.47 µg/m³
O₃: 0.050 ppm
NO₂: 0.4 ppb
SO₂: 0.4 ppb
CO: 0.16 ppm

Health Recommendations:

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

5 PM

47 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 9.41 µg/m³
PM₁₀: 19.05 µg/m³
O₃: 0.051 ppm
NO₂: 0.5 ppb
SO₂: 0.4 ppb
CO: 0.15 ppm

Health Recommendations:

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

6 PM

46 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 9.19 µg/m³
PM₁₀: 18.43 µg/m³
O₃: 0.050 ppm
NO₂: 0.6 ppb
SO₂: 0.4 ppb
CO: 0.15 ppm

Health Recommendations:

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

7 PM

45 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 8.97 µg/m³
PM₁₀: 17.72 µg/m³
O₃: 0.049 ppm
NO₂: 0.8 ppb
SO₂: 0.4 ppb
CO: 0.15 ppm

Health Recommendations:

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

8 PM

44 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 8.84 µg/m³
PM₁₀: 17.14 µg/m³
O₃: 0.047 ppm
NO₂: 0.9 ppb
SO₂: 0.4 ppb
CO: 0.15 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:

PM_2.5: 8.94 µg/m³
PM₁₀: 16.79 µg/m³
O₃: 0.047 ppm
NO₂: 1 ppb
SO₂: 0.4 ppb
CO: 0.15 ppm

Health Recommendations:

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

10 PM

42 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 9.21 µg/m³
PM₁₀: 16.72 µg/m³
O₃: 0.046 ppm
NO₂: 1.1 ppb
SO₂: 0.3 ppb
CO: 0.15 ppm

Health Recommendations:

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

11 PM

42 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 9.53 µg/m³
PM₁₀: 16.8 µg/m³
O₃: 0.045 ppm
NO₂: 1.2 ppb
SO₂: 0.4 ppb
CO: 0.16 ppm

Health Recommendations:

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

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Hayward

Moderate Expected Likely

Heat Advisory

Heat Advisory issued September 8 at 1:15PM PDT until September 10 at 10:00PM PDT by NWS San Francisco CA

Sep 8, 1:15 PM → Sep 10, 10:00 PM

WHAT: Hot conditions with temperatures 10 to 20 degrees above
normal during the day, with overnight lows also running 10 to 20
degrees above normal.

WHERE: Bay Area and Central Coast.

WHEN: Until 10 PM PDT Thursday.

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.

+ Read More

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: Sep 8, 1:46 PM Source: NWS Alert

Minor Expected Likely

Coastal Flood Advisory

Coastal Flood Advisory issued September 8 at 9:03AM PDT until September 10 at 1:00AM PDT by NWS San Francisco CA

Sep 8, 8:00 PM → Sep 10, 1:00 AM

WHAT: Up to 1.2 ft of inundation above ground level is
possible in low-lying areas near shorelines and tidal waterways.

WHERE: Bayshore locations along the San Francisco Bay, San
Pablo Bay, and Monterey Bay.

WHEN: From 8 PM this evening to 1 AM PDT Thursday.

IMPACTS: Flooding of lots, parks, and roads with only
isolated road closures expected.

ADDITIONAL DETAILS: At the San Francisco tidal gauge, high tide
is expected to be 1.2 ft above normal (6.99 ft MLLW) at 9:59 PM
Tuesday 9/8 and 1.0 ft above normal (6.79 ft MLLW) at 10:54 PM
Wednesday 9/9. These predictions include up to 0.6 ft of storm
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: Sep 8, 1:46 PM Source: NWS Alert

Hourly Air Quality Forecast - AQI (US EPA)

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Weather Alerts and Warnings for Hayward

Heat Advisory

Coastal Flood Advisory

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