The hidden cost of a beach summer: humidity
Coastal summers look mild on paper. The humidity tells a different story.
The thermometer on the coast looks kind: the median August high within 5 km of the sea is 29.1°C, against 32.9°C more than 100 km inland. But the coast is far more humid. Its median August dew point is 19.0°C, which feels oppressive, against 10.5°C inland, which feels dry. And the nights stay warm: a median 64 nights a year on the coast stay at 20 °C (68 °F) or above, against 18 inland.
Average August dew point by distance to the sea (°C)
The muggiest Augusts
| Place | Region | Aug dew point | Aug high | Warm nights / year |
|---|---|---|---|---|
| Cartagena | Murcia | 21.5°C | 30.5°C | 104 |
| Águilas | Murcia | 21.5°C | 30.4°C | 103 |
| Mazarrón | Murcia | 21.5°C | 29.9°C | 88 |
| Palma | Balearic Islands | 21.3°C | 30.1°C | 87 |
| Calvià | Balearic Islands | 21.3°C | 29.5°C | 77 |
| Torrevieja | Valencian Community | 21.2°C | 31.0°C | 73 |
| Eivissa | Balearic Islands | 21.2°C | 30.4°C | 77 |
| Santa Eulària des Riu | Balearic Islands | 21.2°C | 30.4°C | 77 |
| Torre-Pacheco | Murcia | 21.2°C | 29.6°C | 67 |
| San Javier | Murcia | 21.2°C | 29.7°C | 71 |
| Sant Josep de sa Talaia | Balearic Islands | 21.2°C | 29.1°C | 49 |
| San Pedro del Pinatar | Murcia | 21.2°C | 29.7°C | 71 |
What it means
In the afternoon the dry inland heat is still the fiercer one. The coast's problem is the evening and the night: humid air cools slowly, so the warmth and the stickiness last until morning, and that is what makes sleeping hard. If heat bothers you, look at the dew point and the warm nights as well as the daytime temperature; both are on every place page and in the sliders under “More weather”. The north coast is the exception: its August dew points reach at most 17.4°C, below the oppressive range, because the air there is cooler.
How we did this
AEMET 1991-2020 station averages; dew point from vapour pressure or humidity measured at the station or a nearby station. Places with only a satellite humidity estimate are left out. Distance to the sea: Natural Earth coastline. Built 2026-10-18.