As summer arrives, most of us pull out the shorts, test out the air conditioning and get the pool ready. But if you wait for summer at the end of June, it’s too late for most of us to beat the heat. The first 90-degree day of the year generally arrives in spring.
FOX Weather crunched 30 years of weather data to figure out when cities across the U.S. hit 90 for the first time, generally. Only one city on our list usually hits 90 for the first time in Summer. That is why you will hear FOX Weather talk about meteorological spring and summer along with solstices and equinoxes.
WHY SUMMER SHOULD ACTUALLY BEGIN ON JUNE 1
Meteorological summer is the warmest 3 months of the year across the U.S.; June, July, and August. Even though the sun is at its northernmost point in late July, it takes the earth and oceans a little time to warm up and cool down, so there is a lag.
The first city to hit 90, on average, is Phoenix, March 30. This is not surprising because the city is so dry that afternoon heating doesn’t net thunderstorms to cool the area down. It is also far away from the ocean which is slow to warm up.
HERE’S WHEN THE SUNSHINE STATE’S RAINY SEASON GETS UNDERWAY
Los Angeles holds the record for earliest 90-degree day on January 8, 1923. Offshore winds, called Santa Ana Winds, blow from the east and warm as they descend the mountains outside the city. Compressional heating warms air 30 degrees with every mile down, according to a UCLA professor. That warms up the land despite the chilly sea temperatures.
Dallas is not far behind L.A. with the record early 90 degrees on January 31, 1911. On average, Dallas hits 90 on April 26.
Miami’s first 90-degree day is usually April 7 while the earliest the city hit 90 was March 2, 2003. The warm Gulf Stream Current keeps Miami warm.
THE REASON CALIFORNIA BEACH SURF IS SO MUCH CHILLIER THAN ATLANTIC, GULF COAST WATERS
THESE ARE THE ALL-TIME HOTTEST TEMPERATURES EVER RECORDED IN EACH STATE
Seattle generally hits 90 around July 2, for the latest date on our list. Cool sea temperatures and onshore winds keep the city very moderate. Seattle’s record earliest date is May 17, 2008.
Detroit comes in with the latest record for first 90 degree day. Motor City residents usually have to wait until June 10 to feel the heat. In 1895, the city hit 90 on May 5.
Not on our list is Anchorage because the only time in recorded history the city hit 90 was July 4, 2019, according to NOAA. That was also the all-time record high for the city.
The NWS records show that Eureka, California has never hit 90 degrees.