January in Arecibo is the sunniest month of the year. In January, the weather in Arecibo is typically warm. Average daily high temperature in January is about 26 degrees above zero. On average, Arecibo has 25 sunny, 4 partly cloudy, and 2 rainy days in January. The rains are usually light. January as well as February is considered the most comfortable time to visit Arecibo.