Climatological averages, historical records, packing tips and best time to visit Barcelona during September. AEMET / ECMWF reanalysis 1991-2020.
Reference values based on 1991-2020 AEMET / ECMWF climatology. Year-to-year variation can be significant.
| Metric | Value | Date |
|---|---|---|
| All-time high | 39.8 °C | August 2010 |
| 24h rainfall | 156 mm | September 1962 |
| All-time low | -7.1 °C | January 1985 |
| Urban snowfall | 20 cm | March 2010 |
Official records (AEMET). Secondary stations may have more extreme readings.
In September, Barcelona typically shows intense storms and frequent DANA events. The average high temperature is around 26°C and the average low around 17°C, with monthly rainfall of 87 mm spread over roughly 7 rain days and about 217 hours of sunshine. Average relative humidity stands at 73% and wind speed averages 11 km/h.
The local calendar in September is shaped by La Merce (24 September), so checking the forecast a few days in advance is worth it before any outdoor activity. Averages give a general picture but extreme events can vary widely: in September, Barcelona has recorded both unusually warm spells and cold incursions across recent decades.
For a typical stay we recommend umbrella and rain jacket. UV protection is sensible on sunny days, even in a mild winter month, and a closed-toe waterproof shoe helps on damp days. For multi-day trips bring thin layers that you can combine through the day.
The first two weeks of September usually offer the best balance in Barcelona: moderate crowds, friendlier prices and weather that remains representative of the month. Late September starts showing features of the transition to the next month. Use our custom historical lookup to check the actual values for the exact year you plan to travel.
Of the twelve months, September is the 3rd warmest in Barcelona and the 2nd wettest. It collects 65 mm, 14 % of the whole year’s rain, spread over 7.6 days with appreciable precipitation, of which 2.1 exceed 10 mm. The warmest month is August and the wettest is October.
Among the 50 Spanish cities with AEMET climatological normals on this site, in September Barcelona is the 35th warmest, with a mean maximum of 25.1 °C, and the 10th wettest. The wettest of them that month is San Sebastián, with 117 mm against Barcelona’s 65 mm.
Averages hide what can actually happen. At the Barcelona, Port Olímpic observatory, a September has reached 30.7 °C as an absolute maximum and 12.7 °C as a minimum: that is the real range to reckon with, not the 22.4 °C mean. Relative humidity runs around — % and mean wind 13.2 km/h.
AEMET climatological normals 1991-2020, Barcelona, Port Olímpic observatory (26 m above sea level). Sources and methodology → · Forecast for Barcelona →
