September weather forecast
Castellón de la Plana, Spain

September in Castellón de la Plana ushers in slowly lowering temperatures while still retaining characteristics of summer warmth. A significant decline in sea temperature to 24.4°C (75.9°F) indicates the gradual onset of autumn. Though the sunlight hours decrease, the number of rainfall days escalates resulting in a total of 71mm (2.8") rainfall, the highest in the year. Weather triggers a transition from summer to autumn but still remains favourable for outdoor activities.

Temperature

The arrival of September records an average high-temperature of a warm 27.6°C (81.7°F), closely related to the 30.3°C (86.5°F) observed in August. In Castellón de la Plana, an average temperature of 18.1°C (64.6°F) is noted during September nights.

Heat index

Throughout September, the heat index is calculated to be a tropical 30°C (86°F). Prolonged exposure combined with continuous activity could lead to exhaustion, and possibly heat cramps.
It is essential to grasp that the heat index's numbers are for shade and light wind settings. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'feels like' or 'felt air temperature', ties air temperature with relative humidity to produce the perceived temperature sensation. The perception of temperature can be subjective, varying based on activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Remember, direct sunlight exposure can heighten the heat impact and might increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Youngsters often neglect the necessity for rest and hydration. Thirst is a sign of advancing dehydration - thus the importance of maintaining hydration, specifically during long-lasting physical activities.

Humidity

The average relative humidity in September is 68%.

Rainfall

September is the month with the most rainfall in Castellón de la Plana. Rain falls for 5 days and accumulates 71mm (2.8") of precipitation.

Sea temperature

In Castellón de la Plana, in September, the average water temperature is 24.4°C (75.9°F).
Note: Imagine a swim in 24.4°C (75.9°F) waters. How you'd feel depends on your cold sensitivity, the sun's rays, the caress of the wind, and the warmth enveloping you. Comparatively, Olympic swimmers train in waters between 25°C (77°F) and 28°C (82.4°F).

Daylight

In September, the average length of the day in Castellón de la Plana is 12h and 27min.
On the first day of the month, sunrise is at 07:28 and sunset at 20:31. On the last day of September, sunrise is at 07:56 and sunset at 19:44 CEST.

Sunshine

In September, the average sunshine in Castellón de la Plana is 7.6h.

UV index

In Castellón de la Plana, Spain, the average daily maximum UV index in September is 6. A UV Index estimate of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for average individuals.
Note: In September, the UV index of 6 transforms into the following advice:
Guard oneself from overexposure. Defence against sun injury is vital. The Sun's UV radiation is most potent between 10 a.m. and 4 p.m. Try to limit direct exposure to the Sun during this period. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Be careful! The Sun's UV radiation is accentuated by reflecting off sand and water.