Summer in Oklahoma means humidity. And lush green vegetation.
And certain smells - hot asphalt after rain, a certain musty smell after the rain, the flowering trees.
Smells are the strongest memory triggers.
I remember fishing on the banks of the creek with my Grandparents. Catching fireflies in the dim light and putting them in canning jars to have "flashlights." Laying in bed at night so hot you couldn't sleep, listening to the crickets chirp outside and praying for a breeze!