The Costa Blanca by season, autumn 2026

Before the months: this coast is not one climate. Dénia is classed Köppen Csa, properly Mediterranean¹. Benidorm and Alicante, an hour south, are classed hot semi-arid — BSh²³. That is a real line on a map and it lands between towns this site covers.

Winter

January is the coldest month everywhere on this stretch and the numbers barely move across it: about 12 °C mean in Alicante, 12.4 °C in Benidorm, about 12 °C in Dénia³²¹. Benidorm and Alicante both record more than 3,000 hours of sun a year; Dénia about 2,750²¹.

The sea is at its coldest in February, around 14 °C⁴. Nobody is swimming. That is not what winter here is for.

Note what these figures do not tell you: whether the town you picked is open. Mean temperature and shutter position are different questions, and only one of them is in a climate table.

Spring

The sea climbs from roughly 15 °C in March to 19 °C in May⁴, which is to say it lags the air by about two months. Spring on this coast is warm before it is swimmable.

It is also the dry half of the year. The wet season here is autumn, not spring — in Dénia more than 300 mm of the annual 750 falls after summer¹, and in Xàbia September, October and November are the wettest months⁵.

Summer

August is the hottest month: 27 °C mean in Benidorm, 26.5 °C in Alicante, about 26 °C in Dénia²³¹. The sea reaches about 26 °C in the same month⁴.

The figure that decides whether you can work is not the daytime one. In Benidorm the average minimum stays above 20 °C right through the summer months — tropical nights, in the technical sense². A room that does not cool down overnight is a room you sleep badly in, and the next day is the one you were supposed to be working.

July is close to rainless in Dénia¹. That is usually printed as an advantage. In a month with no cloud and no night-time relief, it is not obviously one.

Autumn

Autumn is when this coast gets its weather, and it does not arrive politely. The mechanism is the gota fría, or DANA — an isolated depression at high altitude that drags cold air over a Mediterranean still holding its summer heat, and drops the result inland⁶. It is a September-to-November phenomenon, worst when the sea is warmest.

The numbers show it plainly. Dénia takes over 300 mm of its 750 mm in autumn, across roughly fifteen stormy days¹. Alicante’s entire annual total is 284.5 mm³ and Benidorm’s is 291 mm². Dénia can take a whole Alicante year in one season.

How bad this gets is not hypothetical. On 29 October 2024 a DANA killed between 240 and 248 people in Spain; Turís recorded 184.6 mm in a single hour, a national record, and Chiva close to 500 mm in a day⁷. The worst of it fell on Valencia province — Horta Sud and Ribera Alta — rather than on this stretch of Alicante province⁷. That distinction matters for planning and it is not a guarantee about the next one.

If you are choosing between an autumn in the north of this coast and an autumn in the south, the rain figures are the argument, and they are not close.

TK: which towns actually close, and when. That is a question about shutters and bus timetables rather than about weather, and it is answered by staying rather than by reading.

References

1. en.wikipedia.org/wiki/Dénia ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷

2. en.wikipedia.org/wiki/Benidorm ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

3. en.wikipedia.org/wiki/Alicante ↩ ↩² ↩³ ↩⁴

4. weather-and-climate.com/average-monthly-water-Temperature,alicante,Spain ↩ ↩² ↩³

5. es.wikipedia.org/wiki/Jávea ↩

6. en.wikipedia.org/wiki/Cold_drop ↩

7. en.wikipedia.org/wiki/2024_Spanish_floods ↩ ↩²