One of the cooler places in the Northern Hemisphere right now is the coast of California, Oregon, Washington

 i recently listed the temperatures from Seattle to San Diego which are some of the lowest temperatures this far south in the northern Hemisphere right now. As the heat builds inland this sucks the moisture and fog and clouds in off they ocean, then this covers the sun and reduces the temperatures and gives moisture to the trees and plants along the coast from WAshington to Southern California. So, if you want to be cooler these are some of the places to go to stay cooler. So, today for example, you can be  122 degrees in Death Valley or you can be:

Eureka 63

San Francisco 66

Santa Monica 75

San Diego 74

And in San Diego it is presently raining too from Monsoon weather from Mexico off of the Pacific Ocean.