Planning for the weather is a good way to make your trip to Cobourg relaxing and enjoyable, especially when you’re splurging. The hottest months are usually October and November, with an average temperature of 29°C, while the coldest months are July and August, with an average of 26°C. The rainiest months in Cobourg are January, February, December and March, with each month seeing an average of 327 mm of rainfall.