Where is the sea warmest in North America?
The warmest water in North America month by month, across 103 coastal cities — and how many of them are comfortable enough to swim in.
| Month | Warmest city | Sea | Comfortable |
|---|---|---|---|
| January | Acapulco de Juárez | 28.4°C | 26 of 103 |
| February | Acapulco de Juárez | 28.2°C | 26 of 103 |
| March | Acapulco de Juárez | 27.8°C | 33 of 103 |
| April | Ciudad del Carmen | 28.6°C | 40 of 103 |
| May | Ciudad del Carmen | 30.0°C | 41 of 103 |
| June | Ciudad del Carmen | 30.2°C | 50 of 103 |
| July | San Felipe | 30.8°C | 65 of 103 |
| August | San Felipe | 31.9°C | 68 of 103 |
| September | San Felipe | 31.1°C | 67 of 103 |
| October | Puerto Vallarta | 30.3°C | 54 of 103 |
| November | Acapulco de Juárez | 29.5°C | 40 of 103 |
| December | Acapulco de Juárez | 29.2°C | 31 of 103 |
"Comfortable" means at least 19.0°C, which is a judgement and not a fact — a Norwegian and a Spaniard genuinely disagree. Every city page shows the season at four thresholds instead of insisting on one. Method and sources