Planning for the weather is a good way to make your trip to Goderich relaxing and enjoyable, especially when you’re splurging. The hottest months are usually August and July with an average temp of 64°F, while the coldest months are February and January with an average of 28°F. The snowiest months in Goderich are January, November, February, and March, with each month seeing an average of 5 inches of snowfall.