August in Port Coquitlam is the warmest month of the year. In August, the weather in Port Coquitlam is typically warm. Average daily high temperature in August is about 21 degrees above zero. On average, Port Coquitlam has 17 sunny, 9 partly cloudy, 4 rainy, and 1 cloudy day in August. The rains are usually light. August as well as July is considered the most comfortable time to visit Port Coquitlam.