Contra Costa County, California weather alerts
No watches, warnings or advisories are in force for Contra Costa County.
Checked Sun, Sep 20, 2026, 3:05 PM PDT. Times are Pacific Daylight Time.
Warnings on the map
Every watch, warning and advisory the National Weather Service has in force over Contra Costa County, California. Open it for the live map, where it pans and zooms.
Open the live map with warnings and watches
Map layer from NOAA National Weather Service. Boundaries from the Iowa Environmental Mesonet.
Alerts in force
Nothing is in force for Contra Costa County right now. Its warnings come from the National Weather Service and appear here within a minute of being issued; every one of the past year is below.
The past year in Contra Costa County
In the past year the National Weather Service issued 71 alerts for Contra Costa County, including 1 coastal flood warning, 1 extreme cold warning, 1 flash flood warning and 1 high wind warning.
| Product | Issued | Most recent |
|---|---|---|
| Coastal Flood Warning | 1 | Jan 2, 2026 |
| Extreme Cold Warning | 1 | Feb 20, 2026 |
| Flash Flood Warning | 1 | Dec 25, 2025 |
| High Wind Warning | 1 | Dec 23, 2025 |
| Red Flag Warning | 1 | Jun 10, 2026 |
| Extreme Cold Watch | 1 | Jan 9, 2026 |
| Flood Watch | 1 | Dec 23, 2025 |
| High Wind Watch | 1 | Dec 23, 2025 |
| Flood Advisory | 14 | Feb 17, 2026 |
| Dense Fog Advisory | 13 | Feb 26, 2026 |
| Coastal Flood Advisory | 10 | Sep 8, 2026 |
| Cold Weather Advisory | 10 | Feb 21, 2026 |
| Heat Advisory | 9 | Sep 8, 2026 |
| Wind Advisory | 7 | May 17, 2026 |
Warnings issued
Every alert, most recent first
- Coastal Flood Advisory
- Heat Advisory
- Heat Advisory
- Coastal Flood Advisory
- Heat Advisory
- Heat Advisory
- Heat Advisory
- Heat Advisory
- Coastal Flood Advisory
- Coastal Flood Advisory
- Heat Advisory
- Red Flag Warning
- Wind Advisory
- Heat Advisory
- Dense Fog Advisory
- Cold Weather Advisory
- Cold Weather Advisory
- Extreme Cold Warning
- Flood Advisory
- Flood Advisory
- Coastal Flood Advisory
- Dense Fog Advisory
- Coastal Flood Advisory
- Cold Weather Advisory
- Cold Weather Advisory
- Cold Weather Advisory
- Cold Weather Advisory
- Extreme Cold Watch
- Cold Weather Advisory
- Flood Advisory
- Flood Advisory
- Flood Advisory
- Coastal Flood Advisory
- Wind Advisory
- Coastal Flood Warning
- Coastal Flood Advisory
- Cold Weather Advisory
- Dense Fog Advisory
- Cold Weather Advisory
- Flash Flood Warning
The 40 most recent of 71.
From the Iowa Environmental Mesonet’s archive of NWS watches, warnings and advisories (VTEC), by the county’s own code and the forecast zones inside it. Each date links to the event at the IEM.
Nearby
The counties around Contra Costa County, with what is in force in each.
What this means
- Warning
- The hazard is happening or about to. Act now: a tornado warning means take shelter, a flash flood warning means move to higher ground.
- Watch
- Conditions favor the hazard. Nothing is happening yet; have a plan and be ready to act if a warning follows.
- Advisory
- A hazard that is less serious than a warning but can still cause trouble, such as dense fog, heat or light ice.
- Statement
- Information about weather that does not yet meet a warning: a strong storm, a hydrologic update, or a special weather statement.
Severity (extreme, severe, moderate, minor) is the rating the issuing office gives each product. More on the difference: tornado watch vs. tornado warning. Alerts come from the National Weather Service; follow its instructions and your local officials.
Sources
Alerts from the National Weather Service's public feed, read afresh every minute, and matched to counties and zones by their UGC codes. Warnings from outside the United States come from each country's own meteorological service. Follow the issuing office's instructions and your local officials.