What the averages say
The mean annual temperature is 17.4 °C. The warmest month is August, averaging 25.2 °C with highs around 27.6 °C; the coldest is January, averaging 11.3 °C with lows of 8.1 °C. The 20 degrees between the mean high of August and the mean low of January are the real measure of how continental this climate is.
Heat, cold and extremes
On average, 5 days a year reach 30 °C or more and 0 bring frost. Neither heat nor cold dominates the year. The highest reading in the series is 35.9 °C, set in July, and the lowest -1.3 °C, in January.
Rain, sun and wind
460 mm fall each year over 76 days with measurable rain, an amount with a summer clearly drier than the rest of the year: October is the wettest month with 75 mm and June the driest with 18 mm. The sky is clear on — days a year. Mean wind speed is around 12 km/h and mean annual relative humidity 35 %.
Month by month
AEMET climate normals 1991-2020. Barcelona, Port Olímpic observatory, 26.2 km from the centre at 26 m above sea level.| Monthly mean | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|
| Mean temperature | 11.3 | 11.3 | 13.1 | 15.1 | 18.1 | 21.9 | 24.7 | 25.2 | 22.4 | 19.1 | 14.4 | 11.9 |
|---|
| Mean high | 14.5 | 14.4 | 16.0 | 17.7 | 20.6 | 24.3 | 27.0 | 27.6 | 25.1 | 21.9 | 17.5 | 14.9 |
|---|
| Mean low | 8.1 | 8.2 | 10.1 | 12.4 | 15.4 | 19.4 | 22.4 | 22.8 | 19.7 | 16.2 | 11.3 | 8.8 |
|---|
| Rainfall (mm) | 33 | 30 | 38 | 46 | 31 | 18 | 25 | 28 | 65 | 75 | 38 | 33 |
|---|
| Rain days | 6.4 | 5.9 | 6.9 | 8.1 | 7.3 | 4.3 | 3.6 | 5.5 | 7.6 | 7.7 | 6.2 | 6.2 |
|---|
| Days ≥ 30 °C | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.5 | 1.5 | 3.0 | 0.1 | 0.0 | 0.0 | 0.0 |
|---|
| Frost days | 0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
|---|
Where this data comes from
These are the 1991-2020 climate normals published by AEMET, the Spanish state meteorological agency, for the Barcelona, Port Olímpic observatory — the nearest official station with a complete series to Mataro today. One caveat: no station with a complete normal series sits inside Mataro today, and the nearest one that does is 26.2 km away at 26 m, so these figures describe its surroundings rather than the city itself. A normal is not a forecast: it describes a thirty-year average, and any given day can depart from it widely. For tomorrow, use the forecast at the top of this page.