The USA resorts with the warmest sea water temperature in September are Key West, Islamorada and Key Largo.
Below you can see a list of all popular USA resorts and information about sea water temperature in September for the last two years.
| Resort Name | September 2025 | September 2024 | September 2023 |
|---|---|---|---|
| Key West | 91.0°F | 91.6°F | 91.4°F |
| Islamorada | 90.8°F | 91.4°F | 91.1°F |
| Key Largo | 90.6°F | 91.3°F | 90.8°F |
| Fort Lauderdale | 90.4°F | 90.5°F | 90.2°F |
| Everglades | 90.2°F | 91.1°F | 90.9°F |
| West Palm Beach | 90.2°F | 90.4°F | 90.2°F |
| Miami Beach | 90.2°F | 90.3°F | 90.3°F |
| Naples | 90.1°F | 91.4°F | 90.9°F |
| Mustang Island | 90.0°F | 88.4°F | 91.0°F |
| Marco Island | 90.0°F | 91.3°F | 90.8°F |
| South Padre Island | 90.0°F | 89.7°F | 90.3°F |
| Hialeah | 89.8°F | 90.0°F | 90.0°F |
| Corpus Christi | 89.8°F | 88.5°F | 91.2°F |
| Miami | 89.7°F | 90.0°F | 90.0°F |
| Port Aransas | 89.7°F | 88.5°F | 91.1°F |
| Sanibel Island | 89.6°F | 91.1°F | 90.4°F |
| Galveston Island | 89.5°F | 88.2°F | 90.6°F |
| Galveston | 89.4°F | 87.5°F | 90.6°F |
| Cape Coral | 89.1°F | 90.6°F | 90.0°F |
| Grand Isle | 89.1°F | 88.2°F | 90.5°F |
| Houston | 88.7°F | 87.1°F | 90.1°F |
| Siesta Key | 88.7°F | 90.9°F | 89.8°F |
| Sarasota | 88.7°F | 90.8°F | 89.7°F |
| Cocoa Beach | 88.5°F | 89.1°F | 88.3°F |
| Avery Island | 88.5°F | 87.9°F | 89.4°F |
| Tampa | 88.2°F | 90.0°F | 89.4°F |
| New Orleans | 88.1°F | 86.5°F | 89.0°F |
| Gulf Shores | 88.1°F | 88.1°F | 89.4°F |
| Port St. Lucie | 88.1°F | 88.8°F | 88.4°F |
| Dauphin Island | 88.0°F | 87.5°F | 88.7°F |
| St. Petersburg | 87.9°F | 90.2°F | 89.2°F |
| Pass Christian | 87.9°F | 86.8°F | 88.3°F |
| Gulfport | 87.8°F | 87.0°F | 88.1°F |
| Long Beach | 87.8°F | 86.9°F | 88.2°F |
| Orange Beach | 87.8°F | 87.9°F | 89.3°F |
| Mobile | 87.8°F | 87.2°F | 88.4°F |
| Clearwater Beach | 87.8°F | 90.2°F | 89.4°F |
| Bay Saint Louis | 87.8°F | 86.8°F | 88.2°F |
| Ocean Springs | 87.8°F | 86.9°F | 88.2°F |
| Biloxi | 87.7°F | 87.0°F | 88.1°F |
| Pensacola Beach | 87.7°F | 88.3°F | 88.9°F |
| Pensacola | 87.6°F | 88.0°F | 88.3°F |
| St. George Island | 87.3°F | 87.8°F | 88.5°F |
| Panama City Beach | 87.1°F | 88.7°F | 89.0°F |
| Santa Rosa Beach | 87.1°F | 88.6°F | 89.2°F |
| Fort Walton Beach | 86.9°F | 88.4°F | 88.9°F |
| Miramar Beach | 86.9°F | 88.5°F | 89.1°F |
| Destin | 86.8°F | 88.4°F | 88.9°F |
| Orlando | 86.5°F | 87.4°F | 87.1°F |
| Daytona Beach | 86.3°F | 86.9°F | 87.2°F |
| St. Augustine | 85.3°F | 86.4°F | 87.1°F |
| Kauai | 85.0°F | 82.6°F | 83.7°F |
| Princeville | 85.0°F | 82.7°F | 83.7°F |
| Jacksonville | 84.6°F | 85.6°F | 86.4°F |
| Kihei | 84.5°F | 84.1°F | 83.3°F |
| Lanai | 84.5°F | 84.3°F | 83.5°F |
| Amelia Island | 84.4°F | 85.3°F | 86.0°F |
| Kailua Kona | 84.3°F | 84.5°F | 83.9°F |
| Jekyll Island | 84.1°F | 85.5°F | 85.5°F |
| St. Simons Island | 84.1°F | 85.4°F | 85.4°F |
| Honolulu | 84.0°F | 84.4°F | 83.5°F |
| Hawaii | 83.9°F | 84.2°F | 83.4°F |
| Molokai | 83.8°F | 83.7°F | 83.8°F |
| Hilo | 83.8°F | 83.5°F | 83.2°F |
| Kahului | 83.6°F | 83.3°F | 82.9°F |
| Maui | 83.2°F | 83.0°F | 82.7°F |
| Oahu | 83.2°F | 83.3°F | 82.9°F |
| Hilton Head Island | 83.2°F | 83.6°F | 85.8°F |
| Tybee Island | 83.1°F | 83.7°F | 85.6°F |
| Wilmington Island | 83.1°F | 83.9°F | 85.0°F |
| Edisto Beach | 82.8°F | 83.0°F | 85.5°F |
| Kiawah Island | 82.5°F | 82.9°F | 85.4°F |
| Folly Beach | 82.2°F | 82.5°F | 85.3°F |
| Charleston | 82.0°F | 82.1°F | 85.8°F |
| Isle of Palms | 82.0°F | 82.5°F | 84.7°F |
| Mount Pleasant | 81.9°F | 82.3°F | 85.3°F |
| Myrtle Beach | 81.8°F | 82.8°F | 84.0°F |
| Arcadian Shores | 81.7°F | 82.9°F | 84.0°F |
| Pawleys Island | 81.7°F | 82.6°F | 83.9°F |
| North Myrtle Beach | 81.7°F | 82.8°F | 83.9°F |
| Murrells Inlet | 81.6°F | 82.7°F | 84.0°F |
| Oak Island | 81.6°F | 82.4°F | 84.3°F |
| Bald Head Island | 81.5°F | 82.0°F | 84.1°F |
| Carolina Beach | 81.2°F | 81.5°F | 83.3°F |
| Wilmington | 81.1°F | 81.5°F | 83.4°F |
| Wrightsville Beach | 81.0°F | 81.7°F | 83.5°F |
| North Topsail Beach | 80.8°F | 81.6°F | 83.6°F |
| Hatteras Island | 78.2°F | 78.6°F | 82.0°F |
| Outer Banks | 78.1°F | 77.8°F | 80.7°F |
| Nags Head | 77.6°F | 77.2°F | 79.8°F |
| Washington | 77.4°F | 78.0°F | 80.2°F |
| Chesapeake | 77.4°F | 80.1°F | 82.6°F |
| Kill Devil Hills | 77.4°F | 77.3°F | 79.7°F |
| Corolla | 77.4°F | 76.9°F | 79.7°F |
| Annapolis | 77.3°F | 77.6°F | 79.2°F |
| Baltimore | 77.0°F | 77.2°F | 78.9°F |
| Norfolk | 76.9°F | 79.6°F | 81.9°F |
| Tangier Island | 76.4°F | 77.7°F | 80.4°F |
| Virginia Beach | 76.4°F | 76.6°F | 79.3°F |
| Saint Michaels | 76.4°F | 77.3°F | 79.6°F |
| New Castle | 76.2°F | 76.3°F | 78.5°F |
| Wilmington | 76.0°F | 76.0°F | 78.2°F |
| Ocean City | 75.5°F | 74.0°F | 77.1°F |
| Chincoteague | 75.5°F | 74.9°F | 77.8°F |
| Fenwick Island | 75.3°F | 74.1°F | 76.4°F |
| Bethany Beach | 75.2°F | 74.0°F | 76.2°F |
| South Bethany | 75.2°F | 74.0°F | 76.2°F |
| Dewey Beach | 75.2°F | 74.0°F | 76.3°F |
| Rehoboth Beach | 75.0°F | 73.9°F | 76.6°F |
| Lewes | 75.0°F | 74.0°F | 76.8°F |
| Cape May | 74.7°F | 73.7°F | 76.6°F |
| Wildwood Crest | 74.6°F | 73.6°F | 76.5°F |
| Wildwood | 74.6°F | 73.6°F | 76.5°F |
| Sea Isle City | 74.3°F | 73.6°F | 75.9°F |
| Ocean City | 74.1°F | 73.6°F | 75.9°F |
| Atlantic City | 74.0°F | 73.7°F | 75.7°F |
| Beach Haven | 73.9°F | 73.6°F | 75.4°F |
| Long Beach Island | 73.8°F | 73.5°F | 75.4°F |
| Brigantine | 73.8°F | 73.6°F | 75.4°F |
| Yonkers | 73.6°F | 73.5°F | 74.4°F |
| Stamford | 73.6°F | 74.1°F | 74.9°F |
| Cleveland | 73.6°F | 74.6°F | 74.5°F |
| Newark | 73.6°F | 73.0°F | 74.7°F |
| Seaside Heights | 73.5°F | 73.4°F | 74.2°F |
| New York | 73.5°F | 72.9°F | 74.6°F |
| Jersey City | 73.5°F | 72.9°F | 74.7°F |
| Norwalk | 73.5°F | 73.9°F | 74.6°F |
| Sandusky | 73.3°F | 74.8°F | 74.5°F |
| Milford | 73.2°F | 73.6°F | 73.9°F |
| Port Clinton | 73.1°F | 74.3°F | 74.3°F |
| Put in Bay | 73.0°F | 74.8°F | 74.4°F |
| Santa Catalina Island | 72.9°F | 71.3°F | 71.8°F |
| Los Angeles | 72.9°F | 70.9°F | 71.0°F |
| New Haven | 72.8°F | 72.9°F | 73.4°F |
| Fire Island | 72.6°F | 72.1°F | 74.6°F |
| Beverly Hills | 72.6°F | 70.8°F | 70.4°F |
| Hollywood | 72.6°F | 70.8°F | 70.4°F |
| Santa Monica | 72.6°F | 70.7°F | 70.5°F |
| Toledo | 72.5°F | 74.5°F | 73.3°F |
| Hampton Bays | 72.3°F | 71.8°F | 73.4°F |
| Westbrook | 71.9°F | 70.9°F | 71.7°F |
| Fremont | 71.8°F | 70.6°F | 70.8°F |
| Bristol | 71.8°F | 70.8°F | 73.1°F |
| Falmouth | 71.8°F | 71.0°F | 72.9°F |
| Evanston | 71.7°F | 74.0°F | 71.7°F |
| San Jose | 71.7°F | 70.5°F | 70.7°F |
| Newport Beach | 71.7°F | 70.3°F | 70.0°F |
| Erie | 71.7°F | 72.9°F | 73.6°F |
| Malibu | 71.7°F | 68.7°F | 69.9°F |
| New Bedford | 71.6°F | 70.8°F | 73.5°F |
| Warwick | 71.5°F | 70.6°F | 72.7°F |
| Santa Ana | 71.5°F | 70.0°F | 69.8°F |
| Irvine | 71.5°F | 70.3°F | 69.9°F |
| Old Saybrook | 71.3°F | 70.0°F | 71.7°F |
| Providence | 71.2°F | 70.3°F | 72.3°F |
| New London | 70.9°F | 68.7°F | 70.8°F |
| Michigan City | 70.8°F | 73.1°F | 72.7°F |
| Newport | 70.8°F | 69.8°F | 72.2°F |
| Groton | 70.8°F | 68.7°F | 70.8°F |
| Montauk | 70.8°F | 69.3°F | 70.8°F |
| Jamestown | 70.7°F | 70.2°F | 72.1°F |
| Anaheim | 70.7°F | 69.1°F | 69.1°F |
| Santa Barbara | 70.6°F | 67.1°F | 68.4°F |
| Laguna Beach | 70.5°F | 70.6°F | 70.1°F |
| Dennis Port | 70.5°F | 69.7°F | 71.1°F |
| South Haven | 70.5°F | 71.2°F | 70.3°F |
| Stonington | 70.2°F | 68.3°F | 69.7°F |
| Mystic | 70.2°F | 68.3°F | 69.7°F |
| Westerly | 70.2°F | 68.6°F | 70.1°F |
| Edgartown | 70.2°F | 68.4°F | 71.7°F |
| Charlestown | 70.1°F | 68.9°F | 70.7°F |
| Block Island | 70.0°F | 68.4°F | 70.0°F |
| New Shoreham | 70.0°F | 68.4°F | 70.2°F |
| Rochester | 70.0°F | 71.3°F | 71.9°F |
| Buffalo | 69.9°F | 72.0°F | 71.9°F |
| Martha's Vineyard | 69.9°F | 67.8°F | 71.7°F |
| Oshkosh | 69.7°F | 72.7°F | 70.8°F |
| Nantucket | 69.7°F | 68.1°F | 70.3°F |
| Oak Park | 69.7°F | 74.0°F | 71.7°F |
| Saugatuck | 69.5°F | 71.2°F | 69.5°F |
| Holland | 69.5°F | 70.9°F | 69.0°F |
| Oxnard | 69.5°F | 66.4°F | 67.8°F |
| Appleton | 69.4°F | 72.6°F | 71.0°F |
| Long Beach | 69.4°F | 67.7°F | 68.1°F |
| San Diego | 69.3°F | 71.3°F | 69.4°F |
| Oakland | 69.1°F | 67.0°F | 68.6°F |
| Green Bay | 69.0°F | 72.0°F | 69.7°F |
| Milwaukee | 68.8°F | 73.3°F | 69.4°F |
| Chula Vista | 68.5°F | 70.8°F | 68.9°F |
| Traverse City | 68.3°F | 70.0°F | 68.7°F |
| Niagara Falls | 68.2°F | 70.3°F | 70.6°F |
| Incline Village | 68.0°F | 66.2°F | 67.1°F |
| Siasconset | 68.0°F | 67.1°F | 66.5°F |
| South Lake Tahoe | 67.7°F | 65.9°F | 66.5°F |
| Stateline | 67.7°F | 66.0°F | 66.5°F |
| Lake Tahoe | 67.6°F | 65.8°F | 66.6°F |
| Yosemite | 67.3°F | 67.3°F | 67.3°F |
| Chatham | 67.2°F | 66.5°F | 67.0°F |
| Harbor Springs | 66.9°F | 69.3°F | 67.2°F |
| Petoskey | 66.8°F | 69.4°F | 67.4°F |
| Provincetown | 66.8°F | 66.3°F | 67.4°F |
| Chicago | 66.7°F | 74.0°F | 71.8°F |
| Charlevoix | 66.5°F | 69.0°F | 66.6°F |
| San Francisco | 66.4°F | 64.4°F | 66.3°F |
| Sausalito | 66.3°F | 63.9°F | 65.8°F |
| Plymouth | 66.1°F | 66.3°F | 67.4°F |
| Sturgeon Bay | 65.7°F | 69.4°F | 66.5°F |
| Cambridge | 65.4°F | 66.2°F | 67.4°F |
| Boston | 65.3°F | 66.0°F | 67.4°F |
| Salem | 64.5°F | 65.2°F | 67.1°F |
| Astoria | 64.4°F | 64.4°F | 67.2°F |
| Bayfield | 64.1°F | 66.2°F | 65.1°F |
| Freeport | 64.0°F | 62.8°F | 65.0°F |
| Brunswick | 63.5°F | 62.7°F | 64.0°F |
| Kennebunkport | 63.5°F | 62.4°F | 65.5°F |
| Wells | 63.5°F | 62.2°F | 65.6°F |
| Ogunquit | 63.5°F | 62.3°F | 65.6°F |
| York Beach | 63.3°F | 62.8°F | 65.6°F |
| Mackinac Island | 63.3°F | 66.1°F | 63.2°F |
| Old Orchard Beach | 63.2°F | 62.2°F | 65.1°F |
| Marquette | 63.0°F | 65.3°F | 62.4°F |
| Hampton | 62.9°F | 63.6°F | 66.0°F |
| Hampton Beach | 62.9°F | 63.6°F | 66.2°F |
| Camden | 62.6°F | 61.6°F | 62.7°F |
| Santa Cruz | 62.5°F | 59.9°F | 62.3°F |
| Portsmouth | 62.4°F | 62.4°F | 65.1°F |
| Monterey | 61.9°F | 58.1°F | 61.8°F |
| Duluth | 61.9°F | 67.0°F | 66.4°F |
| Rockland | 61.4°F | 60.3°F | 62.2°F |
| Bellingham | 60.9°F | 58.7°F | 59.0°F |
| Mount Desert Island | 59.6°F | 58.8°F | 60.2°F |
| Grand Marais | 59.5°F | 65.2°F | 62.1°F |
| Ocean Shores | 59.5°F | 60.3°F | 61.4°F |
| Tacoma | 59.5°F | 58.6°F | 58.6°F |
| Bar Harbor | 59.4°F | 58.6°F | 60.0°F |
| Whidbey Island | 59.4°F | 59.2°F | 58.2°F |
| Bellevue | 58.1°F | 57.8°F | 57.6°F |
| Ketchikan | 57.8°F | 55.4°F | 56.1°F |
| Seaside | 56.2°F | 57.4°F | 58.3°F |
| Depoe Bay | 55.5°F | 55.8°F | 55.3°F |
| Cannon Beach | 55.4°F | 57.3°F | 58.2°F |
| Newport | 55.4°F | 56.0°F | 55.6°F |
| Sitka | 55.3°F | 53.7°F | 55.2°F |
| Lincoln City | 55.1°F | 55.6°F | 54.9°F |
| Pacific City | 55.0°F | 55.9°F | 55.6°F |
| Kenai | 54.6°F | 53.1°F | 52.7°F |
| Florence | 54.5°F | 54.9°F | 53.9°F |
| Seward | 54.5°F | 52.7°F | 53.5°F |
| Anchorage | 54.3°F | 52.9°F | 52.5°F |
| Juneau | 53.8°F | 50.9°F | 52.5°F |
| Rockaway Beach | 53.8°F | 56.0°F | 55.3°F |
| Valdez | 52.2°F | 52.5°F | 52.7°F |
| Haines | 52.2°F | 50.4°F | 52.2°F |
| Port Angeles | 52.2°F | 51.0°F | 52.1°F |
| Homer | 52.0°F | 51.3°F | 51.4°F |
| Girdwood | 51.6°F | 50.2°F | 51.9°F |
| Wasilla | 51.4°F | 50.9°F | 50.8°F |
| Kissimmee | 30.0°F | 30.0°F | 87.0°F |
| Lake Geneva | 30.0°F | 30.0°F | 70.3°F |
Please see following sea water temperature averages charts for the warmest USA resorts in September.
You can also get the same information for the every other month of the year when the average sea water temperature is greater then 70°F.
USA Resorts:
NAME
F°
| Chicago |  |
0 |
| Hawaii |  |
+78 |
| Honolulu | |
+78 |
| Houston | |
+46 |
| Las Vegas |  |
+40 |
| Los Angeles | |
+52 |
| Maui | |
+72 |
| Miami | |
+72 |
| Miami Beach | |
+80 |
| New York | |
+18 |
| San Diego | |
+54 |
| San Francisco | |
+46 |
| Sarasota | |
+62 |
| Tampa | |
+62 |
| Washington | |
+28 |
