When is the Hottest Day of the Year?

August 17, 2021
Lightning and Cactus

When is the hottest time of the year? You might expect summer temperatures to peak in July, however, this is not typical for all regions of the United States. Take a look at your neck of the woods!

For most of the country, July is the hottest month of the year.  Many regions in the United States—from the Rockies to the East Coast—follow this pattern.

However, this isn’t true for all regions. See the map below.

  • While Northern regions usually reach their peak temperatures in July, oceans continue to warm until September. Warm wet Gulf air continues to warm Texas, Louisiana and Florida through August.
  • If you live in most of the West or the Southern Plains, it will hit you in the next few weeks.
  • And, if you are on the West Coast, you will have to wait a couple of months.

 

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Summer heat peaks in different times of the year. Source NOAA. See enlarged map here.

 

Then, there’s the Desert Southwest which usually peaks in June. The welcome monsoon rains arrive in July and sheltering clouds cool the landscape.

Monsoon rains cool Southwestern summers through July and August. Source: Wikipedia

Finally, there’s California. The currents along the West Coast flow from Alaska. When the chill Pacific air hits the warm land, it creates cooling fog. Summertime can be quite chill. As a famous quote falsely attributed to Mark Twain goes, “The coldest winter I ever spent was a summer in San Francisco.”

It isn’t until September, when northern oceans reach their peak, that most of the West Coast finally warms up.

The cool Pacific current off the West Coast creates a chilling fog for most of the summer. Source: NOAA

Of course, every year is different! How’s the summer temperature in your area this year? Please comment below.

About This Blog

Mike Steinberg is Senior Vice President for Special Initiatives at AccuWeather Inc in State College, Pennsylvania. He is also a member of the National Weather Association and the Canadian Meteorological and Oceanographic Society.

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