July is the peak summer month and the apex of the average temperature graph here in the Northern Plains. On average, our hottest time of the year is at the end of July and the beginning of August.
Of course, in any given summer, our hottest weather can happen at any time during the summer owing to the natural random variability of weather. Interestingly, July is not the hottest month throughout all of the Northern Hemisphere, however.
Across the deserts of the American Southwest, the hottest temperatures are more often in June, before the hot temperatures begin to draw humidity in from the Gulf of Baja. In Texas, the hottest days are usually in August, when the ground has become parched after a summer’s worth of evaporation. Along coastal areas of California and Oregon, the so-called Santa Ana winds bring the hottest weather of the year from the deserts up and over the Coast Ranges during September and October.