Why is Florida #1 in average temperature?
Ever heard that the desert is the hottest place around? In NOAA's numbers for 2024, the state with the warmest year was not a desert state at all. It was Florida. The background is not blazing afternoons. It is warm water next door, very humid air, and humid nights that cool off more slowly.
In NOAA's numbers for 2024, Florida had the highest yearly average temperature of all 50 states. That average mixes everything together: days and nights, summer and winter. Check the ranking in the quiz below. On this site Florida is also #1 for marinas, sightseeing boat businesses, farm-raised aquarium fish, squash and watermelons, each with its own source on its quiz page. Another note compares Florida's kind of hot with Arizona's.
Basis: NOAA NCEI Climate at a Glance, statewide average temperature, January–December 2024. The numbers, the full ranking and the source are on the quiz page.
Why so warm? NOAA's State Climate Summary for Florida explains that Florida sits at subtropical latitudes (the warm belt just outside the tropics) and right next to the warm waters of the Gulf of Mexico and the western Atlantic Ocean. That gives it hot, humid summers and mild winters. In summer, a big high-pressure system out over the Atlantic, called the Bermuda High, usually pulls moist ocean air over the state, bringing frequent thunderstorms in the afternoons and evenings. Here is the surprise: Florida has far fewer days above 100°F than most other southern states. But it is the most humid state in the nation.
Who says so: NOAA National Centers for Environmental Information (State Climate Summaries 2022, with CISESS) (opens in a new tab)
What does “humid” mean? The Florida Climate Center at Florida State University says weather scientists like to measure moisture with the dew point: the temperature the air would have to cool down to before it is full (saturated) and its extra water vapor starts turning into dew or cloud droplets. The higher the dew point, the more water vapor is in the air. Is Florida the most humid state? The Climate Center's answer is “yes!” Florida is surrounded by the warm Gulf of Mexico and Atlantic Ocean, and South Florida has a nearly tropical climate. In summer, dew points run high every day, no matter what part of the state you are in. The most humid city in Florida is Key West, surrounded by the warm Atlantic Ocean.
Who says so: Florida Climate Center (Office of the State Climatologist, Florida State University) (opens in a new tab)
So why don't Florida nights cool off much? A lesson for weather forecasters, written at Penn State and posted on a National Weather Service website, explains the science. After sunset, the ground starts to cool because it gives off more energy than it gets back from the air. But on a clear, calm night with plenty of water vapor, the vapor sends infrared energy (invisible heat rays) back down to the ground, which slows the ground's cooling. The warmer ground then sends more energy up for the vapor to soak up. This give-and-take keeps both the ground and the air warmer than they would otherwise be, so the night's lowest temperature stays higher. Forecasters even use a rule of thumb: on clear, calm nights, the dew point is a good guess for how low the temperature can go. The opposite happens in dry air: the lesson says the coldest nights usually come when the air is bone dry, the sky is clear and the wind is light.
Remember, an average hides things. The Florida Climate Center points out that Florida isn't always warm in winter. Sometimes a powerful blast of arctic air pushes all the way into the state. In February 1899, the “Great Arctic Outbreak” brought Florida its coldest temperature ever recorded. Hard freezes over the years helped push Florida's famous orange groves south, away from the Jacksonville and St. Augustine area. And yes, it does snow in Florida! The first documented account dates to 1774, and in January 2025 a historic winter storm covered parts of the Panhandle, including Pensacola, in snow.
Who says so: Florida Climate Center (Office of the State Climatologist, Florida State University) (opens in a new tab)
What may change? NOAA's State Climate Summary says Florida has already gotten warmer since the early 1900s, and the change has shown up mostly at night: there has been little daytime warming, but warm nights have increased a lot since the mid-1990s. Looking ahead, climate models project that Florida could keep warming through this century. How much depends partly on future greenhouse gas emissions: models show less warming in a future where emissions grow more slowly. The summary also projects that hurricane rain could get heavier as the climate warms.
Who says so: NOAA National Centers for Environmental Information (State Climate Summaries 2022, with CISESS) (opens in a new tab)
Note: a “theory”, “folklore” or “outlook” is not settled fact. Always check who is saying it.
📊 Sources for the rankings mentioned in this note (links to the original data and retrieval dates) are on each quiz page below.