It was brought to my attention this weekend in pittsburg, that some may be weary of convention in Canada, as it is too cold here

from the weather channel webpage

In the Summer (Late June to September) the temperatures in Niagara can equal or be hotter than those of California, USA. Temperatures can range from 59F to over 88F and there is a tendency for high humidity in the summer months. Normal clothing would be light fabrics, short sleeves and short pants presuming your culture permits.