It’s the middle of summer. Are you hot yet? NOAA has released a map showing when you can normally expect the hottest day of the year.
For some people, it arrived in June or early July and cooler days lie ahead. 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.
Summer heat peaks in different times of the year. Source NOAA. See enlarged map here.
The longest day of the year is usually around June 20 to 21. Typically, the long sunny days bake the land and, for most of the Northern Hemisphere, land temperatures peak sometime in July. Most of the US, from the Rockies to the East Coast follows that pattern. But notice that some areas are really different.
The Desert Southwest usually peaks in June. Then the welcome monsoon rains arrive in July and sheltering clouds cool the landscape.
Monsoon rains cool Southwestern summers through July and August. Source: Wikipedia
While northern lands 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.
Then there is 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, this is a very crazy year. Have you had a heat wave yet or is spring's cool weather lingering into your July? Share it with us here!
Evelyn Browning Garriss, historical climatologist, is a longtime writer for The Old Farmer's Almanac. She is also editor of The Browning World Climate Bulletin and has advised farmers, businesses, and investors worldwide on upcoming climate events and their economic and social impact for the past 21 years.