| Radio Beach | California | Coastal Waters | 14.5°C(58.1°F) | July, August, September, October | Live SST → |
| Ragged Point Beach | Virginia | Coastal Waters | 24.3°C(75.7°F) | July, August, September | Live SST → |
| Rainbow Beach | Illinois | James Bay | 20.2°C(68.4°F) | July, August, September, October | Live SST → |
| Rainbow Beach | United States | Caribbean Sea | 29.2°C(84.6°F) | January, February, March, April, May, June, July, August, September, October, November, December | Live SST → |
| Rat Beach | California | Gulf of California | 20.3°C(68.5°F) | July, August, September, October | Live SST → |
| Red Rock Beach | California | Coastal Waters | 14.5°C(58.1°F) | July, August, September, October | Live SST → |
| Red Sand Beach | Hawaii | Coastal Waters | 26.6°C(79.9°F) | January, February, March, April, May, June, July, August, September, October, November, December | Live SST → |
| Redman Beach | United States | James Bay | 14.6°C(58.3°F) | July, August, September, October | Live SST → |
| Redondo Beach | California | Gulf of California | 14.9°C(58.8°F) | July, August, September, October | Live SST → |
| Rest House Shore | Massachusetts | Coastal Waters | 19.1°C(66.4°F) | July, August, September, October | Live SST → |
| Rialto Beach | Washington | Coastal Waters | 13.5°C(56.3°F) | June, July, August, September | Live SST → |
| Rice's Beach | Massachusetts | James Bay | 17.5°C(63.5°F) | June, July, August, September | Live SST → |
| Rincon beach | California | Gulf of California | 18.8°C(65.8°F) | July, August, September, October | Live SST → |
| Rincon Beach | California | Gulf of California | 18.8°C(65.8°F) | July, August, September, October | Live SST → |
| Rio Del Mar Beach | California | Gulf of California | 14.9°C(58.8°F) | August, September, October, November | Live SST → |
| Riverhead Beach | Massachusetts | James Bay | 17.6°C(63.7°F) | June, July, August, September | Live SST → |
| Robert W. Crown Memorial State Beach | California | Coastal Waters | 14.5°C(58.1°F) | July, August, September, October | Live SST → |
| Robinsons Beach | New Jersey | James Bay | 21.8°C(71.2°F) | June, July, August, September | Live SST → |
| Rockaway Beach | California | Coastal Waters | 14.7°C(58.5°F) | July, August, September, October | Live SST → |
| Rockaway Beach | United States | James Bay | 21.8°C(71.2°F) | June, July, August, September | Live SST → |
| Rocky Beach | Connecticut | James Bay | 22.1°C(71.8°F) | July, August, September | Live SST → |
| Rodeo Beach | California | Coastal Waters | 14.5°C(58.1°F) | July, August, September, October | Live SST → |
| Rogers Park Beach | Florida | Gulf of Mexico | 29.1°C(84.4°F) | May, June, July, August, September, October | Live SST → |
| Roque Island Ledge | Maine | James Bay | 12.3°C(54.1°F) | July, August, September, October | Live SST → |
| Rosario Beach | Washington | Coastal Waters | 11.4°C(52.5°F) | June, July, August, September | Live SST → |
| Rosemont Avenue Beach | Illinois | James Bay | 20.2°C(68.4°F) | July, August, September, October | Live SST → |
| Round Hill Beach | Massachusetts | James Bay | 20.2°C(68.4°F) | June, July, August, September | Live SST → |
| Rowayton Community Beach | Connecticut | James Bay | 22.3°C(72.1°F) | July, August, September | Live SST → |
| Roy Carpenter's Beach | Rhode Island | James Bay | 19.7°C(67.5°F) | July, August, September, October | Live SST → |
| Ruby Beach | Washington | Coastal Waters | 14°C(57.2°F) | June, July, August, September | Live SST → |
| Russian Gulch | California | Coastal Waters | 13.1°C(55.6°F) | August, September, October, November | Live SST → |
| Rye North Beach | New Hampshire | James Bay | 16.9°C(62.4°F) | June, July, August, September | Live SST → |
| S-Turns Beach | Hawaii | Coastal Waters | 26.9°C(80.4°F) | January, February, March, April, May, June, July, August, September, October, November, December | Live SST → |
| Saint Malo Beach | California | Gulf of California | 21.3°C(70.3°F) | July, August, September, October | Live SST → |
| Salem Willows Beach | Massachusetts | James Bay | 17.5°C(63.5°F) | June, July, August, September | Live SST → |
| Salomon Beach | United States | Caribbean Sea | 29.2°C(84.6°F) | January, February, March, April, May, June, July, August, September, October, November, December | Live SST → |
| Salty Brine State Beach | Rhode Island | James Bay | 19.7°C(67.5°F) | July, August, September, October | Live SST → |
| Sam Ferretti Blue Shutters Town Beach | Rhode Island | James Bay | 19.7°C(67.5°F) | July, August, September, October | Live SST → |
| Samish Beach | Washington | Coastal Waters | 11.4°C(52.5°F) | June, July, August, September | Live SST → |
| Sammys Beach | New York | James Bay | 20.4°C(68.7°F) | July, August, September, October | Live SST → |
| San Carlos Beach | California | Gulf of California | 14.9°C(58.8°F) | August, September, October, November | Live SST → |
| San Diego (La Jolla Cove) | California | Pacific Ocean | 21°C(69.8°F) | Jul, Aug, Sep | Live SST → |
| San Gregorio Beach | California | Gulf of California | 14.9°C(58.8°F) | July, August, September, October | Live SST → |
| San Gregorio Private Beach | California | Gulf of California | 14.9°C(58.8°F) | July, August, September, October | Live SST → |
| San Luis Beach | Texas | Gulf of Mexico | 29.2°C(84.6°F) | May, June, July, August, September, October | Live SST → |
| San Pedro Beach | California | Coastal Waters | 14.7°C(58.5°F) | July, August, September, October | Live SST → |
| Sand Beach | California | Gulf of California | 14.9°C(58.8°F) | July, August, September, October | Live SST → |
| Sand Beach | Maine | James Bay | 12.8°C(55°F) | July, August, September, October | Live SST → |
| Sand Beach | Maine | James Bay | 13.5°C(56.3°F) | July, August, September, October | Live SST → |
| Sand Dollar Beach | California | Gulf of California | 15.3°C(59.5°F) | August, September, October, November | Live SST → |