April in Willemstad is the cloudiest month of the year. In April, the weather in Willemstad is typically warm. Average daily high temperature in April is about 27 degrees above zero. On average, Willemstad has 12 partly cloudy, 10 cloudy, 7 sunny, and 1 rainy day in April. The rains are usually light. April as well as February, March, and May is considered the most comfortable time to visit Willemstad.