Today | Weather | Monday, May 18, 2026

Active Weather Warnings

Weather in Roseville, California

04:51 AM

Now

57° F

Feels Like 54°

Precipitation 0 %

Wind 9 mph

Humidity 35 %

Today

Day 84°

Night 54°

Precipitation 1 %

Wind 12 mph

UV Index (0 - 11+) 10

Warning: High UV Index Today: 10

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

Roseville Weather Forecast Updated

44 minutes ago

Last updated on May 18, 2026 at 4:07 AM

Weather Forecast History

Last Year's Weather on This Day (May 18, 2025)

Day

82°

Night

55°

Wind

9 mph

UV Index

Precipitation

0 %

Air Quality in Roseville

NOW

44 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 0.5 µg/m³

PM₁₀ 0.71 µg/m³

O₃ 0.047 ppm

NO₂ 1.1 ppb

SO₂ 0.3 ppb

CO 0.11 ppm

NH₃ 1.22 µg/m³

NO 0 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 – 0.5 µg/m³

PM₁₀ – 0.71 µg/m³

O₃ – 92.69 µg/m³

NO₂ – 2.05 µg/m³

SO₂ – 0.72 µg/m³

CO – 127.08 µg/m³

NH₃ – 1.22 µg/m³

NO – 0 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Roseville

Severe Future Possible

Fire Weather Watch

Fire Weather Watch issued May 14 at 10:24AM PDT until May 18 at 8:00PM PDT by NWS Sacramento CA

May 16, 5:00 AM → May 18, 8:00 PM

The National Weather Service in Sacramento has issued a Fire
Weather Watch for gusty winds and low humidity, which is in
effect from late Friday night through Monday evening.

* Winds...North winds 15 to 25 mph. Gusts 35 to 45 mph, locally up
to 50 mph around the Delta.

* Humidity...Daytime minimum humidities of 9 to 15%.

* Highest Threat...Along the Interstate 5 corridor in the
Sacramento Valley. Strongest winds are expected Sunday into
Monday.

* Impacts...The combination of gusty winds and low humidity can
cause fire to rapidly grow in size and intensity. Outdoor
burning is not recommended

+ Read More

A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings.

Updated: May 15, 8:56 AM Source: NWS Alert

Severe Expected Likely

Red Flag Warning

Red Flag Warning issued May 17 at 12:07PM PDT until May 18 at 8:00PM PDT by NWS Sacramento CA

May 17, 12:07 PM → May 18, 8:00 PM

* Winds...North winds 20 to 30 mph. Gusts 35 to 45 mph, locally
up to 50 mph around the Delta and the western Sacramento
Valley.

* Humidity...Daytime minimum humidities of 7 to 15%. Overnight
maximum relative humidities of 20 to 45%.

* Highest Threat...Along and west of the Interstate 5 corridor
in the Sacramento Valley. Strongest winds are expected today.

* Impacts...The combination of gusty winds and low humidity can
cause fire to rapidly grow in size and intensity. Outdoor
burning is not recommended.