Temperatures in the United States vary widely. In fact, the country is home to some of the hottest places on earth, as well as its coldest. On one end, frigid Fairbanks, Alaska has an average monthly temperature of -16.9°F (-27°C) during its coldest month, with a lowest-ever-recorded temperature of -66°F (-54.6°C). Meanwhile, temperatures in Death Valley, California average 116.5°F (46.9°C) in July, its hottest month. Death Valley is also home to the highest recorded air temperature in the world, reaching a blistering 134.1°F (56.7°C) on July 10, 1913. With its vast size and varied topography, the United States sees temperatures everywhere between these two extremes.
The hottest states in the country are primarily in the south. The subtropical states along the southern Atlantic border are characterized by hot and humid summers and mild winters. Meanwhile, southwestern states tend to be more arid with low annual precipitation and high temperatures.
The ten hottest states experience average annual temperatures above 60°F (15.5°C) and tend to have fewer seasons than their northern neighbors. According to the National Oceanic and Atmospheric Administration, 2021 was the fourth hottest year on record, with temperatures in the nation's hottest states pushing the mercury even further than in previous years.
The Ten Hottest U.S. States
Florida is the hottest state in the U.S., with an average annual temperature of 71.5°F (21.9°C) between 1991 and 2020. It is the southernmost contiguous U.S. state with a subtropical climate in its northern and central regions and a tropical climate in its southern regions. Winters are mild, and summers are hot and humid. July is the hottest month in Florida, averaging 90°F to 92°F and frequently hitting or going above 100°F.
In 2021, temperatures in the state rose even higher, with a state-wide average of 72.3°F (22.38°C). According to the Florida Climate Center, 2021 was the eleventh straight year with above-average temperatures across the state. The highest temperature recorded in 2021 was 108°F (42.2°C) in Jacksonville.
Hawaii is the second-hottest state in the U.S., with an average annual temperature of 70.2°F. The weather in Hawaii is very consistent, with little variation in average daily temperatures. The state has never reached temperatures below freezing (32ºF / 0°C) or above 100°F (37.7°C).
In the summer months, average temperatures in Hawaii peak around 77.1°F. (25°C) In the past two decades, the hottest month was September 2019, when the average temperature rose to 80.7°F. February tends to be the coldest month, with an average temperature of 72°F (22°C). The coldest month since 2000 was March 2009, when the average temperature fell to 68.8°F (20.4°C).
Louisiana has an average annual temperature of 67.2°F (19.5°C). Louisiana's hottest month is August, where highs range from 89°F to 94°F. The state averages 90 days a year above 90°F (32.2°C). However, Louisiana's position on the Gulf of Mexico means high humidity levels, which can push the heat index up to 120°F (48.9°C).
In 2021, Lousiana saw several extreme weather events, including a hurricane, a freeze, and a tropical storm. The weather was cooler and wetter than in previous years.
Texas is America's fourth-hottest state, with an average annual temperature of 65.8°F (18.8°C). Texas's climate is divided. The state's east side experiences sub-tropical conditions, including high precipitation and humidity. In contrast, the western part of the state is arid and drought-prone. August sees the highest temperatures, ranging from 93°F to 101°F.
In 2021, Texas saw some of its most extreme weather on record. In February, the state experienced an arctic freeze, which caused the entire state to fall under a winter storm warning on Valentine's Day. Temperatures across the state fell below freezing due to the arctic blast that saw records broken across the country. The eastern part of the state saw temperatures in the negative teens. The freeze proved a strain on the state's infrastructure and was one of the costliest weather events ever to hit the state.
Georgia is the fifth-hottest U.S. state. Like its neighbor Florida, the state has a subtropical climate. The average annual temperature is 64.3°F (17.9°C). The southern region of the state has summers ranging from 90°F to 100°F, while the northern part has milder summers ranging from 72°F to 82°F.
Mississippi's average annual temperature of 64.3ºF (17.9°C) makes the state the sixth-hottest in the United States. Like its neighbors in the southeast, Mississippi has a humid subtropical climate characterized by temperate winters and long, hot summers. Mississippi experiences freezing temperatures almost every winter.
Unsurprisingly, another southeastern state is the seventh-hottest in the U.S.: Alabama. Alabama's average annual temperature is 63.7ºF (17.6°C). Alabama's climate is temperate, with the Gulf of Mexico alleviating some of its summer heat. Temperatures are slightly cooler in the northern parts of the state and warmer in the south. Alabama average about 56 inches of rain per year and about 1 inch of snow.
South Carolina is the eighth-hottest state in the United States, with an annual temperature of 63.4ºF (17.4°). The state's subtropical climate gives its long hot summers and mild winters in its eastern and southern regions. The northwestern areas of South Carolina tend to have cold winters, especially at high elevations.
Arkansas ties with Arizona for the ninth hottest state, with an annual average temperature of 61.1ºF (16ºC). Arkansas's climate is a mix of humid subtropical and humid continental. The state experiences hot, humid summers and generally mild, drier winters. Some areas of Arkansas receive a few inches of snow every winter, such as Little Rock, which averages around four inches.
Arizona rounds out the top ten with an average annual temperature of 61.1ºF (16ºC), tying with Arkansas. Pheonix, the state's capital, sees average temperatures of 100ºF throughout June, July, and August every year. However, other parts of the state see much more mild temperatures and even snow in the winter. For example, the Grand Canyon averages a comfortable 80ºF during summer.
States with the Lowest Temperatures
You can read more about the coldest states here.