San Francisco, California

Regional Weather Alerts


     

Alert: Air Quality Alert
Area(s): San Bernardino and Riverside County Valleys-The Inland Empire
Effective: 2026-05-20 @ 7:44 pm -> 2026-05-21 @ 7:45 pm
Onset: 2026-05-20 @ 7:44 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS San Diego CA on 2026-05-20 @ 7:44 pm
Headline: Air Quality Alert issued May 20 at 5:44PM PDT by NWS San Diego CA
Description: * WHAT...The South Coast AQMD has issued an air quality alert due to
increased fine particle pollution from wildfire smoke. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

* WHERE...in portions of Riverside, San Bernardino, and Los Angeles
Counties. Levels of particle pollution can vary by time and
location depending on fire activity and local weather conditions.

* WHEN...until Thursday at 10:00 PM.

* IMPACTS...Particles in wildfire smoke can get deep into the lungs
and cause serious health problems such as heart attacks, strokes,
asthma attacks, and difficulty breathing. Everyone can be affected,
but people with lung or heart disease, older adults, people who are
pregnant, children, and those who spend a lot of time outdoors are
at greater risk.

Alert: Air Quality Alert
Area(s): Eastern San Fernando Valley; Eastern San Gabriel Mountains; Los Angeles County San Gabriel Valley; Santa Clarita Valley; Santa Susana Mountains; Western San Fernando Valley; Western San Gabriel Mountains and Highway 14 Corridor
Effective: 2026-05-20 @ 5:59 pm -> 2026-05-22 @ 12:00 am
Onset: 2026-05-20 @ 5:59 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS Los Angeles/Oxnard CA on 2026-05-20 @ 5:59 pm
Headline: Air Quality Alert issued May 20 at 3:59PM PDT by NWS Los Angeles/Oxnard CA
Description: * WHAT...The South Coast AQMD has issued an air quality alert due to
increased fine particle pollution from wildfire smoke. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

* WHERE...in portions of Los Angeles, Riverside, and San Bernardino
Counties. Levels of particle pollution can vary by time and
location depending on fire activity and local weather conditions.

* WHEN...until 10 PM on Thursday.

* IMPACTS...Particles in wildfire smoke can get deep into the lungs
and cause serious health problems such as heart attacks, strokes,
asthma attacks, and difficulty breathing. Everyone can be affected,
but people with lung or heart disease, older adults, people who
are pregnant, children, and those who spend a lot of time outdoors
are at greater risk.

Alert: Air Quality Alert
Area(s): Imperial Valley
Effective: 2026-05-20 @ 12:06 pm -> 2026-05-21 @ 10:00 pm
Onset: 2026-05-20 @ 12:06 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS Phoenix AZ on 2026-05-20 @ 12:06 pm
Headline: Air Quality Alert issued May 20 at 10:06AM MST by NWS Phoenix AZ
Description: * WHAT...The Imperial County APCD has issued an air quality alert
due to harmful levels of ozone pollution.
Visit https://www.aqmd.gov/alertinfo to check current and forecasted
air quality levels.

* WHERE...the Imperial Valley. Levels of ozone pollution can vary by
time and location depending on emissions and air pollution
transport.

* WHEN...from 11:00 a.m. through 8:00 p.m. Thursday, May 21, 2026.
The highest ozone levels typically occur in the afternoon and
early-evening hours.

* IMPACTS... Ozone air pollution can cause serious health problems,
including trouble breathing, asthma attacks, and lung damage.
Everyone can be affected, but sensitive groups such as people with
lung disease, older adults, people who are pregnant, children, and
those who spend a lot of time outdoors are at greater risk.

Alert: Air Quality Alert
Area(s): Santa Ana Mountains and Foothills; Orange County Coastal; Orange County Inland
Effective: 2026-05-19 @ 11:42 pm -> 2026-05-20 @ 11:45 pm
Onset: 2026-05-19 @ 11:42 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS San Diego CA on 2026-05-19 @ 11:42 pm
Headline: Air Quality Alert issued May 19 at 9:42PM PDT by NWS San Diego CA
Description: * WHAT...The South Coast AQMD has issued an air quality alert due to
increased fine particle pollution from wildfire smoke. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

* WHERE...most of LA County and all of Orange County. Levels of
particle pollution can vary by time and location depending on fire
activity and local weather conditions.

* WHEN...until Tuesday evening.

* IMPACTS...Particles in wildfire smoke can get deep into the lungs
and cause serious health problems such as heart attacks, strokes,
asthma attacks, and difficulty breathing. Everyone can be affected,
but people with lung or heart disease, older adults, people who are
pregnant, children, and those who spend a lot of time outdoors are
at greater risk.

Alert: Air Quality Alert
Area(s): San Bernardino and Riverside County Valleys-The Inland Empire
Effective: 2026-05-19 @ 11:42 pm -> 2026-05-20 @ 11:45 pm
Onset: 2026-05-19 @ 11:42 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS San Diego CA on 2026-05-19 @ 11:42 pm
Headline: Air Quality Alert issued May 19 at 9:42PM PDT by NWS San Diego CA
Description: * WHAT...The South Coast AQMD has issued an air quality alert due to
increased fine particle pollution from wildfire smoke. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

* WHERE...in portions of Riverside, San Bernardino, and Los Angeles
Counties. Levels of particle pollution can vary by time and
location depending on fire activity and local weather conditions.

* WHEN...until Wednesday at 4:30 PM.

* IMPACTS...Particles in wildfire smoke can get deep into the lungs
and cause serious health problems such as heart attacks, strokes,
asthma attacks, and difficulty breathing. Everyone can be affected,
but people with lung or heart disease, older adults, people who are
pregnant, children, and those who spend a lot of time outdoors are
at greater risk.

Alert: Air Quality Alert
Area(s): Santa Ana Mountains and Foothills; Orange County Coastal; Orange County Inland
Effective: 2026-05-19 @ 11:37 pm -> 2026-05-20 @ 11:45 pm
Onset: 2026-05-19 @ 11:37 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS San Diego CA on 2026-05-19 @ 11:37 pm
Headline: Air Quality Alert issued May 19 at 9:37PM PDT by NWS San Diego CA
Description: * WHAT...The South Coast AQMD has issued an air quality alert due to
increased fine particle pollution from wildfire smoke. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

* WHERE...most of LA County and all of Orange County. Levels of
particle pollution can vary by time and location depending on fire
activity and local weather conditions.

* WHEN...until Tuesday evening.

* IMPACTS...Particles in wildfire smoke can get deep into the lungs
and cause serious health problems such as heart attacks, strokes,
asthma attacks, and difficulty breathing. Everyone can be affected,
but people with lung or heart disease, older adults, people who are
pregnant, children, and those who spend a lot of time outdoors are
at greater risk.

Alert: Air Quality Alert
Area(s): San Bernardino and Riverside County Valleys-The Inland Empire
Effective: 2026-05-19 @ 11:37 pm -> 2026-05-20 @ 11:45 pm
Onset: 2026-05-19 @ 11:37 pm
Severity: Unknown
Certainty: Unknown
Urgency: Unknown
Issued By: NWS San Diego CA on 2026-05-19 @ 11:37 pm
Headline: Air Quality Alert issued May 19 at 9:37PM PDT by NWS San Diego CA
Description: * WHAT...The South Coast AQMD has issued an air quality alert due to
increased fine particle pollution from wildfire smoke. Visit
https://www.aqmd.gov/alertinfo to check current and forecasted air
quality levels.

* WHERE...in portions of Riverside, San Bernardino, and Los Angeles
Counties. Levels of particle pollution can vary by time and
location depending on fire activity and local weather conditions.

* WHEN...until Tuesday evening.

* IMPACTS...Particles in wildfire smoke can get deep into the lungs
and cause serious health problems such as heart attacks, strokes,
asthma attacks, and difficulty breathing. Everyone can be affected,
but people with lung or heart disease, older adults, people who are
pregnant, children, and those who spend a lot of time outdoors are
at greater risk.