We are in the final days of spring, and we're looking ahead to summer in Oklahoma. When you start the summer season, you usually begin to look for signs of a summer heat wave begin to take over. This summer, however, looks a bit different. Tolerable start to summer? Summer officially begins on June 21, and we're looking at normal temperatures if not below-average temperatures from Oklahoma up to the north. The heat wave will stay out on the West Coast. And this looks like it will continue into July.