August in Santa Barbara is the hottest month of the year. In August, the weather in Santa Barbara is typically hot. Average daily high temperature in August is about 32 degrees above zero. On average, Santa Barbara has 29 rainy, 1 cloudy, and 1 partly cloudy day in August. The rains are usually heavy. August as well as January, March, April, and May is considered the most uncomfortable time to visit Santa Barbara.