January in Mackay is the cloudiest month of the year. In January, the weather in Mackay is typically warm. Average daily high temperature in January is about 28 degrees above zero. On average, Mackay has 20 rainy, 6 sunny, 3 partly cloudy, and 2 cloudy days in January. The rains are usually heavy. January as well as February and March is considered the most uncomfortable time to visit Mackay.