The Hottest Temperatures Ever Recorded in Every US State

134°F: The Most Controversial Weather Record on Earth

Greenland Ranch was a small outpost near Furnace Creek in Death Valley. On July 10, 1913, observer Oscar Denton recorded 134°F. The World Meteorological Organization certified it as the global record in 2012, after disqualifying a 136.4°F reading from El Azizia, Libya.

But the 134°F reading has serious problems. Weather historian Christopher C. Burt and geographer William T. Reid spent years investigating and concluded the temperature was "essentially not possible from a meteorological perspective." Surrounding stations that day showed a typical heat wave (2.5–4.5°F above average), while Greenland Ranch was 9.3°F above average — a statistical outlier of 4.5 standard deviations. Nearby Independence was 30.4°F cooler. Denton lacked formal Weather Bureau training, entered temperatures for days he was absent, and logged unnaturally repetitive values.

What makes Death Valley so extreme? Furnace Creek sits 190 feet below sea level in a narrow, north-south valley. Surrounding mountains trap hot air and block cooler marine influences. The dark basalt walls radiate heat back into the basin after sunset, keeping overnight lows above 100°F during peak summer. On July 12, 2012, Death Valley recorded an overnight low of 107°F — hotter than most cities' afternoon highs.

All-Time Record High for Every US State

Ranked from hottest to coolest. Every temperature below is the official all-time maximum recorded by NOAA-verified stations. Click any state to see its full weather history and records.

Source: NOAA State Climate Extremes Committee (SCEC), National Weather Service official records. Some state records have disputed or alternative readings — the table uses the most widely accepted official values.

Six Things That Surprised Me in This Data

The Most Extreme Heat Events in American History

Six events that pushed the thermometer to its limits. The oldest still holds the record. The most recent happened last month.

March 2026: The Most Anomalous Month in 132 Years

The numbers from March 2026 are hard to believe. The CONUS average temperature was 50.85°F — a full 9.35°F above the 20th-century baseline. That's the largest departure from average for any month in the entire 132-year US record. Over 7,000 daily temperature records fell. On March 19 alone, 418 daily records broke.

Ten states set their warmest March ever: Arizona, California, Colorado, Idaho, Nevada, New Mexico, Oklahoma, Texas, Utah, and Wyoming. Arizona and California both hit 112°F — beating the national March record by 4°F. Denver reached 85°F when normal highs are 55°F. San Francisco hit 90°F, breaking a 152-year-old record.

A World Weather Attribution study found the event was "virtually impossible without human-induced climate change," estimating that warming added 4.7–7.2°F to observed temperatures. Even in today's climate, this was roughly a once-in-500-year event. Combined with January–March 2026 being the driest start to any year on record, it pushed 59.9% of CONUS into drought.

And the bigger picture: April 2025 through March 2026 is now the warmest 12-month span ever recorded for the contiguous US. For more, read our full March 2026 heat wave analysis.

Record Highs by Region

The Desert Southwest dominates, but the Great Plains run surprisingly close. The Southeast is deceptively mild at the extremes.

Record Highs vs. Record Lows: The Balance Has Broken

Here's the trend that matters most. In a stable climate, new daily record highs and record lows should occur at roughly equal rates. Gerald Meehl's research team at NCAR analyzed millions of daily readings across 1,800 US weather stations. The ratio has been shifting steadily since the late 1970s.

Ratio of new daily record highs to record lows at US weather stations. Bar length represents the proportion of record highs. Source: Meehl et al. (Geophysical Research Letters), NOAA GHCN-Daily, Climate Central.

Frequently Asked Questions

Data Sources & Methodology

State all-time records are from the NOAA State Climate Extremes Committee and National Weather Service official records, cross-referenced with the Wikipedia U.S. state temperature extremes table. Decade trend ratios from Meehl et al. (2009) in Geophysical Research Letters, updated with Climate Central annual analyses. Death Valley controversy sourced from Christopher C. Burt and William T. Reid's investigation published on Weather Underground. March 2026 data from NOAA NCEI, Yale Climate Connections, and the World Weather Attribution rapid attribution study.

Explore Temperature Records by State

Look up all-time record highs, record lows, and 55+ years of temperature history for any state.