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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.

  1. #1
    HOT C A FLUME NR MAMMOTH LAKES CAUSGS gauge · 36 ft³/s
    89°F 32°C20 hrs ago
  2. #271°F 22°C20 hrs ago
  3. #3
    MUD SLOUGH NR GUSTINE CAUSGS gauge · 69 ft³/s
    68°F 20°C19 hrs ago
  4. #468°F 20°C20 hrs ago
  5. #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.

  • 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

  • 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.

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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.