Weekly swim report · October 20, 2026
California swim report
On October 20, 2026 the warmest USGS water reading in California was 89°F at HOT C A FLUME NR MAMMOTH LAKES CA; 2 water-related NWS hazards are active.
Warmest water
The 5 warmest of 106 sensors reporting a water temperature in California today. Station names open the official monitoring page.
- #1HOT C A FLUME NR MAMMOTH LAKES CAUSGS gauge · 36 ft³/s89°F 32°C20 hrs ago
- #2COLORADO RIVER ABOVE IMPERIAL DAM, AZ-CAUSGS gauge71°F 22°C20 hrs ago
- #3MUD SLOUGH NR GUSTINE CAUSGS gauge · 69 ft³/s68°F 20°C19 hrs ago
- #468°F 20°C20 hrs ago
- #568°F 20°C19 hrs ago
Active hazards in California
Alerts cover counties or forecast zones — an alert for an area does not mean every river or beach inside it is affected. Times are local to the issuing office.
- CautionBeach Hazards Statement
A Beach Hazards Statement is in effect for San Diego County Coastal Areas; Orange County Coastal.
NWS San Diego CA · until Oct 20, 11:00 PM
- CautionBeach Hazards Statement
A Beach Hazards Statement is in effect for Ventura County Beaches; Malibu Coast; Los Angeles County Beaches.
NWS Los Angeles/Oxnard CA · until Oct 23, 3:00 AM
Where to swim in California
The most-reviewed, well-rated water destinations in California — check each one’s live conditions before you go.
4.6(131,806)PIER 39
Bustling bayside pier featuring scenic views, sea lion sightings, eateries, shops & entertainment.
4.6(126,928)Santa Monica Pier
Storied seaside destination showcasing a range of shops & cafes, plus an amusement park & aquarium.
4.6(26,119)Redondo Beach Pier
Landmark pier known for scenic oceanfront dining, shopping & nightlife, plus music & festivals.
4.7(17,531)Newport Beach Pier
Scenic pier popular for fishing & ocean views, convenient to beach & nearby shops & restaurants.
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Conditions are for general information only and can change quickly. Always judge the water in person and follow posted advisories and local guidance before swimming or paddling.

