Every U.S. state has experienced temperatures of at least 100°F – even Alaska.
The hottest temperature ever recorded in the United States was 134°F (56.7°C), measured at Death Valley, California, on July 10, 1913. It remains the highest air temperature ever reliably recorded anywhere on Earth.
Many states have also reached temperatures well above 115°F (46.1°C). During the Dust Bowl of 1936, North Dakota soared to 121°F (49.4°C) despite lying just 150 miles (241 km) from the Canadian border. Oklahoma reached 120°F (48.9°C) multiple times that same summer.
More recently, the historic Pacific Northwest heat wave of 2021 rewrote the record books. Washington set a new all-time high of 120°F (48.9°C), while Oregon tied its statewide record of 119°F (48.3°C).
Not every record comes from the Southwest. Minnesota has reached 115°F (46.1°C), Missouri hit 118°F (47.8°C), and even Rhode Island has climbed to 104°F (40°C).
Alaska’s highest temperature stands at exactly 100°F (37.8°C), recorded in Fort Yukon on June 27, 1915. Hawaii has also reached 100°F (37.8°C), with that record set in Pahala on April 27, 1931.
Most all-time state heat records were set in July or August, but a handful occurred during unusual early-season heat waves, showing that extreme temperatures can strike outside the heart of summer.
With more than 260 million Americans currently experiencing dangerous heat, many meteorologists warn that some long-standing state records could eventually come under threat as extreme heat events become more frequent.