In April, the weather in Castellón de la Plana is typically warm. Average daily high temperature in April is about 19 degrees above zero. On average, Castellón de la Plana has 14 sunny, 9 rainy, and 7 partly cloudy days in April. The rains are usually moderate. April as well as January, February, August, and September is considered the most uncomfortable time to visit Castellón de la Plana.