Today | Weather | Tuesday, September 8, 2026

Active Weather Warnings

Weather in Hayward, California

02:41 PM

Now

91° F

Feels Like 93°

Precipitation 0 %

Wind 8 mph

UV Index (0 - 11+) 5

Humidity 27 %

Today

Day 91°

Night 66°

Precipitation 0 %

Wind 6 mph

UV Index (0 - 11+) 7

Hayward Weather Forecast Updated

55 minutes ago

Last updated on September 08, 2026 at 1:46 PM

Weather Forecast History

Last Year's Weather on This Day (September 8, 2025)

Day

81°

Night

63°

Wind

8 mph

Precipitation

65 %

Air Quality in Hayward

NOW

46 AQI

Good air quality Dominant pollutant: O₃

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

NH₃ 0 µg/m³

NO 0.14 µg/m³

PM_2.5 – Fine particles <2.5μm

PM₁₀ – Inhalable particles <10μm

O₃ – Ozone

NO₂ – Nitrogen dioxide

SO₂ – Sulfur dioxide

CO – Carbon monoxide

NH₃ – Ammonia

NO – Nitric oxide

Health Recommendations:

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

Show raw pollutant concentrations (µg/m³)

PM_2.5 – 9.51 µg/m³

PM₁₀ – 19.31 µg/m³

O₃ – 96.94 µg/m³

NO₂ – 0.79 µg/m³

SO₂ – 1.23 µg/m³

CO – 180.01 µg/m³

NH₃ – 0 µg/m³

NO – 0.14 µg/m³

View Hourly Air Quality Forecast

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.

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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: 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.