The best time to go to Saint Thomas, Ontario, is during the summer months, from June to August, or in the early autumn, specifically September.Summer offers the warmest weather, with average daily temperatures often reaching 25°C (77°F) or higher, making it great for outdoor activities. This is when the city truly comes alive with local events and festivals. You'll find attractions like the Elgin County Railway Museum operating on a fuller schedule, and the local parks are at their most inviting.For those who prefer slightly cooler temperatures and fewer crowds, September is an excellent choice. The weather remains pleasant, typically around 18-22°C (64-72°F), and the autumn foliage begins to show its beautiful colours, especially in areas like Pinafore Park. Many of the summer attractions are still open, but with a more relaxed pace. This period is particularly enjoyable for couples looking for a tranquil escape with scenic drives.While spring (April-May) and late autumn (October-November) can also be pleasant, the weather is more unpredictable.