September remains very summery in Barcelona, but the month changes noticeably: the highs drop from 28°C at the beginning to 25.5°C by the end. The sea stays warm at 25.1°C, while the rains return with 68 mm spread over six days.
We are in September - right now in Barcelona
Overcast, feels like 26°C. High 26°C today, sea at 27°C.
Temperatures, rain and sunshine: AEMET station 0076 (Barcelona Aeropuerto), 2016-2025 averages against the 1991-2020 normal. Sea: NOAA OISST, same period. Daylight runs from 13 hr 10 min to 11 hr 51 min across the month.
Early, Mid or Late September?
The weather changes throughout the month. If you're deciding between several dates, here's what sets each period apart. Averages per decade over ten years, AEMET station 0076.
September 1st → 10th
28°C / 20.6°C, 39 mm of rain.
Summer is still in full swing with 28°C during the day. It's also the wettest period of the warm season, with thirty-nine millimeters of rain, which is more than throughout the entire month of August.
September 11 → 20
27°C / 19.3°C, 18 mm of rain.
Temperatures are starting to drop, and the rain is becoming less frequent. Evenings are also more pleasant after the very hot nights of July and August.
September 21 to 30
25.5°C / 17.7°C, 11 mm of rain.
With 25.5°C during the day, the air becomes milder, but the sea still retains much of its warmth. This is often the best time of the month to combine city sightseeing and beach visits.
What to Pack in Your Suitcase
Essential
- Light clothing for the day: temperatures still reach an average of 26.8°C
- A swimsuit and towel: the sea remains very pleasant at 25.1°C
- A compact umbrella for the six rainy days and occasional thunderstorms
- Sunscreen: September still has 217 hours of sunshine and the UV index remains high at noon
Still worth considering
- A light jacket for the end of the month, as evenings drop about three degrees between the 1st and the 30th
- Something to cover your shoulders for the Sagrada Família and the cathedral
- Closed shoes, practical when early month storms leave the streets wet
- Evening attire if you're there at the end of September, when La Mercè brings the city to life
Swimming in Barcelona in September
The sea remains at 25.1°C, just a degree below its August peak, while the air is already starting to cool. This is what makes September particularly enjoyable: you can still fully enjoy the beach while experiencing more comfortable temperatures for sightseeing. The water will remain warm until October.
Summer Without the Crowds
Enjoy the Beach Without Skipping the Sights
September maintains a sea temperature of 25.1°C but receives 68 mm of rain, with the beginning of the month being noticeably wetter. It's ideal to enjoy the beach when the sky is clear and to keep some indoor visits in mind for stormy episodes.
In the morning
La Barceloneta
Under Cover
Cathedral of Barcelona
One hour
Barcelona Design Museum - DHub Barcelona
On the agenda
What to do in Barcelona in September?
September still offers a mix of beach days and major cultural events. Around September 24th, La Mercè, Barcelona's patron saint festival, brings the city to life for several days and is one of the highlights of the year.
September or October?
October loses -3.5°C on the maximum temperatures and receives eight millimeters more rain, but the sea remains at 22.2°C, a temperature comparable to June. For swimming, September clearly holds the advantage.
| August | September | October | |
|---|---|---|---|
| Maximum | 30°C | 26.8°C | 23.3°C |
| Minimum | 22.8°C | 19.2°C | 15.6°C |
| Sea | 26.5°C | 25.1°C | 22.2°C |
| Rain | 45 mm | 68 mm | 76 mm |
| Sunshine | 274 h | 217 h | 175 h |
| Rainy days | 3 | 6 | 6 |
September in the Year
September shows the same average high as June, 26.8°C, but with a much warmer sea and more rain. Two months that are similar in temperature, yet very different in atmosphere.
Frequently Asked Questions About September in Barcelona
Yes, it's actually one of the best months for it. The sea is still at 25.1°C, just slightly cooler than in August, while the air temperatures become more pleasant.
Rainfall increases significantly compared to the summer: 68 mm over six days, with thirty-nine of those occurring in just the first ten days. These episodes are often stormy and sometimes intense, but they don't necessarily last all day.
Yes, especially at the beginning of the month with 28°C during the first ten days. By the end, the highs drop to 25.5°C: it's still mild, but the days become more comfortable for visiting.
September is preferable for swimming and warmth, while October offers a calmer atmosphere. The sea is still at 22.2°C in October, but this month receives 76 mm of rain.
Yes, it's one of the best times to combine city and beach. The intense heat of August begins to subside, while the sea still retains almost all of its summer warmth.