April in Parnaiba is the cloudiest and the coldest month of the year. In April, the weather in Parnaiba is typically hot. Average daily high temperature in April is about 29 degrees above zero. On average, Parnaiba has 28 rainy and 2 sunny days in April. The rains are usually heavy. April as well as January, February, March, and May is considered the most uncomfortable time to visit Parnaiba.