Is the weather hottest in July, August and September every year?

The temperature in July is the highest in the northern hemisphere, followed by August. In China, most of the northern part of September has been crisp in autumn; Summer in the south is still hot, although it is not as hot as in July and August, but the so-called "autumn tigers" appear frequently. In the southern hemisphere, July, August and September are the coldest months. And near the equator at low latitudes, it is summer all year round, so it doesn't matter which month, it is very hot.