Alameda County Warnings, Watches and Advisories

Do not drive vehicles through flooded areas. The water depth or fast flowing water/mud/debris from a flash flood will make road conditions unsafe. Do not rely soley on data presented here or other third-party websites - always check your official national and local weather service agency website, socials, radio and/or TV stations for making critical decisions related to weather events.

Please carefully read each posted Warning and Alert as it relates to the area(s) being affected. We may provide a wider range of issued severe weather warnings for surrounding cities and counties, so some alerts may not directly impact this location. This is done to help with preparing for severe weather that may overlap or be heading towards Alameda County.

Use the Radar Maps link provided to understand the trajectory of a storm.

Dense Fog Advisory issued November 26 at 9:12PM PST until November 27 at 10:00AM PST by NWS Hanford CA

* WHAT...Visibility one quarter mile or less in dense fog. * WHERE...Grapevine and Tehachapi, especially on Highway 58 through Tehachapi Pass and I-5 through the Grapevine * WHEN...Until 10 AM PST Wednesday. * IMPACTS...Low visibility could make driving conditions hazardous.

Frost Advisory issued November 26 at 8:45PM PST until November 27 at 10:00AM PST by NWS Eureka CA

* WHAT...Temperatures as low as 34 will result in frost formation. * WHERE...Humboldt Coast, and Mendocino Coast. * WHEN...From midnight tonight to 10 AM PST Wednesday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered.

Frost Advisory issued November 26 at 8:45PM PST until November 27 at 10:00AM PST by NWS Eureka CA

* WHAT...Temperatures as low as 36 will result in frost formation. * WHERE...Del Norte Coast. * WHEN...From midnight tonight to 10 AM PST Wednesday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered.

Frost Advisory issued November 26 at 8:45PM PST until November 27 at 10:00AM PST by NWS Eureka CA

* WHAT...Temperatures as low as 32 will result in frost formation. * WHERE...Del Norte Interior and Northern Humboldt Interior. * WHEN...From midnight tonight to 10 AM PST Wednesday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered.

Frost Advisory issued November 26 at 1:15PM PST until November 28 at 9:00AM PST by NWS San Francisco CA

* WHAT...Temperatures as low as 32 will result in frost formation. * WHERE...The East Bay Hills and Valleys, The Salinas and Carmel Valleys and Hollister Area, Most of San Benito County and the Cholame Hills in Southeast Monterey County, North Bay Interior Mountains, North Bay Interior Valleys, and Eastern Santa Clara Hills. * WHEN...From 10 PM Wednesday to 9 AM PST Thursday. * IMPACTS...Cold conditions will be hazardous to sensitive populations such as unhoused individuals. Cold Conditions can lead to hypothermia with prolonged exposure.

Air Quality Alert issued November 26 at 10:34AM MST by NWS Phoenix AZ

The Imperial County Air Pollution Control District has declared a mandatory wood burning curtailment for residents within the Calexico area for 9 AM to midnight on Tuesday, November 26. The declaration of a Mandatory curtailment, when forecast indicate elevated levels of fine particulate air pollution in the region, is issued to protect the public health. Smoke from wood burning can cause health problems. Breathing high levels of pollution from wood smoke can cause breathing problems (including asthma attacks), worsened lung and heart disease symptoms, and may even increase emergency room visits and hospitalizations. The Mandatory Curtailment rule prohibits the operation of any wood burning appliances during the curtailment period. This prohibition does not apply to cookstoves and those devices exclusively gaseous- fueled. To view current and forecast air quality within Imperial County visit the Imperial County Air Quality website at http://www.imperialvalleyair.org/ or follow ICAPCD on Twitter, facebook or Instagram (@county_air)

Beach Hazards Statement issued November 26 at 8:30AM PST until November 28 at 10:00PM PST by NWS San Francisco CA

* WHAT...A long period south swell will result in an energetic surf zone and increasing risk of sneaker waves and rip currents. * WHERE...San Francisco, Coastal North Bay Including Point Reyes National Seashore, San Francisco Peninsula Coast, Northern Monterey Bay and Southern Monterey Bay and Big Sur Coast Counties. * WHEN...From this evening through Thursday evening. * IMPACTS...Dangerous swimming and surfing conditions. Large waves can sweep across the beach without warning, pulling people into the sea from rocks, jetties, and beaches. Sudden immersion in cold water can result in cold water shock even for the most experienced swimmers. Cold water shock can result in dramatic changes in breathing, heart rate and blood pressure, greatly increasing the risk of drowning in rough open waters.