August in Arrowtown is the rainiest month of the year. In August, the weather in Arrowtown is typically cold. Average daily high temperature in August is about 4 degrees above zero. On average, Arrowtown has 17 rainy, 9 cloudy, 4 sunny, and 1 partly cloudy day in August. The rains are usually heavy. August as well as January, April, May, and June is considered the most uncomfortable time to visit Arrowtown.