What the averages say
The mean annual temperature is 18.0 °C. The warmest month is August, averaging 26.2 °C with highs around 30.7 °C; the coldest is January, averaging 11.0 °C with lows of 6.4 °C. The 24 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, 56 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 40.6 °C, set in July, and the lowest -2.0 °C, in January.
Rain, sun and wind
435 mm fall each year over 77 days with measurable rain, an amount heavily concentrated in the cold half of the year: September is the wettest month with 60 mm and July the driest with 10 mm. The sky is clear on 81 days a year. Mean wind speed is around 9 km/h and mean annual relative humidity 63 %.
Month by month
AEMET climate normals 1991-2020. Castelló - Almassora observatory, 3.7 km from the centre at 43 m above sea level.| Monthly mean | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|
| Mean temperature | 11.0 | 11.7 | 13.8 | 16.0 | 19.3 | 23.1 | 25.8 | 26.2 | 23.2 | 19.4 | 14.7 | 11.8 |
|---|
| Mean high | 15.6 | 16.4 | 18.7 | 21.0 | 24.1 | 27.9 | 30.4 | 30.7 | 27.8 | 23.9 | 19.1 | 16.1 |
|---|
| Mean low | 6.4 | 6.9 | 8.9 | 11.1 | 14.4 | 18.3 | 21.2 | 21.6 | 18.6 | 15.0 | 10.2 | 7.5 |
|---|
| Rainfall (mm) | 38 | 26 | 45 | 34 | 36 | 19 | 10 | 20 | 60 | 54 | 53 | 40 |
|---|
| Rain days | 6.1 | 5.2 | 6.4 | 8.3 | 8.1 | 5.2 | 3.4 | 5.3 | 7.5 | 7.5 | 7.3 | 6.8 |
|---|
| Days ≥ 30 °C | 0.0 | 0.0 | 0.0 | 0.1 | 0.8 | 7.1 | 19.9 | 22.2 | 5.3 | 0.5 | 0.0 | 0.0 |
|---|
| Frost days | 0.2 | 0.1 | 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 Castelló - Almassora observatory — the nearest official station with a complete series to Castellon de la Plana today. 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.