Tennesseans are already feeling the heat, but the official start to the summer season is still a few days away, and with it comes the longest day of the year.
The first official day of summer astronomically for 2025 isJune 20. This will mark when the Northern Hemisphere has the longest day of the year, according to the Farmer’s Almanac. It also means the dog days of summer are upon us.
It is expected to be hot, muggy and rainy across much of the Volunteer State heading into the official first day of summer. Over the next week, communities in Tennessee will get the first true dose of summer heat as temperatures hit 90 degrees or even exceed it.
Here’s everything you need to know ahead of the official start to summer and the longest day of the year.
When is the first day of summer 2025?
Well, there are technically two answers.
The first official day of summer astronomically for 2025 is June 20, which is when the Northern Hemisphere has the longest day of the year, according to the Old Farmer’s Almanac.
But when we talk meteorologically, summer starts on June 1. The reason for this is because meteorologists divide the year into four seasons based on the months and temperature cycle. Doing it this way also allows them to compare and organize climate data more easily. In this system, summer begins on June 1 and ends on August 31.
What is the summer solstice?
The summer solstice marks the astronomical first day of the summer season in June in the Northern Hemisphere.
This is also when the Earth arrives at the point in its orbit where the North Pole is at its maximum tilt toward the sun, according to the Almanac. This makes it the longest day with the longest period of sunlight hours and shortest night of the calendar year.
It will begin at 2:42 UTC on June 21, which is 9:42 p.m. CT on June 20, according to EarthSky.org.
When is the longest day of the year?
The summer solstice is the longest day of the year. On June 20, it will be the day with the longest period of sunlight, with some areas in the Northern Hemisphere getting upwards of 15 hours of sunlight on that day, according to EarthSky.org.
In Tennessee, communities will see around 14 hours and 40 minutes of daylight on the longest day of the year, according to sunrise-sunset.org, which tracks when sunrise and sunset occurs in communities across the United States.
What was the hottest day in Tennessee?
According to data from the National Oceanic and Atmospheric Administration, the two hottest days on record for Tennessee occurred less than two weeks apart in 1930. Perryville, Tennessee, hit a high of 113 degrees on July 29, 1930, and August 9, 1930.
Summer solstice 2025: When were the hottest starts to summer?
Each year the summer solstice heralds the start of the summer season, but some years have distinctly more spring-like weather.
Here’s what the average temperature was in Tennessee for past summer solstices, according to World Weather, a site that archives weather data from around the world.
This article originally appeared on Nashville Tennessean: Summer solstice 2025: When’s the longest day of the year in Tennessee?