Thunder Bay's humid continental climate produces hot summers and cold winters. However, Lake Superior influences conditions and gives the city cooler summers and warmer winters than other places in the region.The best time to visit is from June to September, when temperatures are warmer. The average high temperature in summer is around 73.4°F (23°C). The hottest month is July, while January is the coldest, when temperatures can dip to -2.2°F (-19°C). Winters can be bitterly cold for visitors not used to extreme temperatures.
