January in Napier is the sunniest and the warmest month of the year. In January, the weather in Napier is typically warm. Average daily high temperature in January is about 21 degrees above zero. On average, Napier has 16 sunny, 12 partly cloudy, and 3 rainy days in January. The rains are usually light. January as well as February and March is considered the most comfortable time to visit Napier.