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Weekly swim report · August 21, 2026

The swim report

On August 21, 2026 the warmest USGS water reading in the United States was 96°F at GULF OF AMERICA NEAR CRYSTAL RIVER FL (Florida); 2,133 sensors reported a temperature and 253 water-related NWS hazards were active.

Warmest water right now

The 10 warmest sensor readings in today’s snapshot. Each links to its state’s report; the station name opens the official monitoring page.

  1. #1 · FloridaGULF OF AMERICA NEAR CRYSTAL RIVER FLUSGS gauge · as of 8 hrs ago96°F36°C
  2. #2 · CaliforniaHOT C A FLUME NR MAMMOTH LAKES CAUSGS gauge · 40 ft³/s · as of 8 hrs ago94°F34°C
  3. #3 · FloridaBLACKWATER RIVER NEAR GOODLAND, FLUSGS gauge · as of 8 hrs ago93°F34°C
  4. #4 · South CarolinaWANDO RIVER AT CAINHOY BELOW WANDO, SCUSGS gauge · as of 8 hrs ago92°F33°C
  5. #5 · FloridaEAST SIDE CREEK NEAR LAKE INGRAHAM, FLUSGS gauge · as of 8 hrs ago92°F33°C
  6. #6 · TexasTrinity Rv at Liberty, TXUSGS gauge · 1,630 ft³/s · as of 8 hrs ago92°F33°C
  7. #7 · South CarolinaSTONO RIVER AT MAIN RD BELOW RANTOWLES, SCUSGS gauge · as of 8 hrs ago92°F33°C
  8. #8 · ArkansasRed River at Index, ARUSGS gauge · 1,960 ft³/s · as of 8 hrs ago92°F33°C
  9. #9 · FloridaSHAKETT CREEK AT CR 762 NR NOKOMIS, FLUSGS gauge · as of 8 hrs ago92°F33°C
  10. #10 · FloridaFAKA-UNION RIVER NEAR THE MOUTHUSGS gauge · as of 9 hrs ago92°F33°C

Active water hazards

253 water-related National Weather Service alerts are in effect, checked live. Alerts cover counties, forecast zones or coastal waters — an alert for an area does not mean every river or beach inside it is affected.

Stay-out warnings47Flood, surf, surge and storm warnings
Caution advisories174Watches, advisories and rip-current statements
Statements and outlooks32Hydrologic outlooks and weather statements

Most common alerts

  • Small Craft Advisory ×90
  • Heat Advisory ×45
  • Special Weather Statement ×29
  • Flood Warning ×25
  • Severe Thunderstorm Warning ×17
  • Extreme Heat Warning ×16
  • Severe Thunderstorm Watch ×6
  • Special Marine Warning ×5

States with active alerts

Every state

Warmest current sensor reading per state, warmest first. States with no sensor reporting a temperature today sit at the end.

Find swimmable water near you →Can I swim today?Water temperature by state

About this report

Water temperatures come from USGS real-time monitoring stations (and NOAA buoys where present), captured in a daily snapshot; only readings taken within the last 48 hours are used. Hazards come live from the National Weather Service alert feed at the moment the page is built, filtered to the events that matter in or on the water. A “warmest reading” is the warmest sensor reading in a state — a point measurement at one gauge, usually on a river or stream — not a claim about its warmest lake or beach. Sensor coverage varies widely by state and USGS data is provisional.

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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.