The numbers are now official — and they are terrifying.
In its July 2025 climate summary, the National Oceanic and Atmospheric Administration (NOAA) confirmed that five locations across the American Southwest shattered their all-time maximum temperature records during an unrelenting June heat wave. Some of these records had stood for decades. One of them is now the hottest reliably measured temperature on Earth in nearly a century.
If you thought 2024 was extreme, June 2025 just rewrote the history books.
The Five Cities That Recorded the Hottest Temperatures Ever Measured
1. Death Valley, California – On June 18, 2025, the mercury at Furnace Creek soared to 54.1°C (129.4°F). This beat the previous modern-era record of 54.0°C (129.2°F) set in July 2024 and now stands as the highest verified temperature anywhere on the planet since 1931.
2. Needles, California – This small Colorado River town hit 51.7°C (125°F) on June 19, 2025 — a full 2°C (3.6°F) above its previous all-time high and the hottest temperature ever recorded in California outside of Death Valley.
3. Phoenix, Arizona – Sky Harbor International Airport reached 50.0°C (122°F) on June 25, 2025, finally breaking a record of 49.4°C (121°F) that had stood since June 26, 1990 — 35 years ago.
4. Las Vegas, Nevada – Harry Reid International Airport tied its all-time record at 48.9°C (120°F) on June 24, but the real shock was the duration: 17 straight days above 46.1°C (115°F), smashing the previous record streak of just 10 days.
5. Tucson, Arizona – Tucson International Airport climbed to 47.2°C (117°F) on June 25, 2025, eclipsing the old record of 46.7°C (116°F) from 1990 and capping a month with an astonishing 22 days at or above 43.3°C (110°F).
Why June 2025 Was Historically Extreme
A blocking high-pressure ridge — often called a “heat dome” — parked itself over the Desert Southwest for nearly three weeks, preventing any cooling Pacific air from reaching the region. At the same time:
- Record-low snowpack in the Sierra Nevada and Rocky Mountains caused the ground to heat up faster than normal.
- Background global warming has added roughly 1.4°C (2.5°F) to what these extremes would have been in the 1980s.
- Soil moisture in Arizona and Nevada dropped to the lowest June levels ever measured by NOAA satellites.
The result? Temperatures that climatologists describe as “virtually impossible” in a pre-industrial climate.
The Human Cost You Didn’t See on the Thermometer
Behind every record-breaking degree were real lives lost:
- Maricopa County (Phoenix metro) confirmed 312 heat-related deaths in June 2025 alone — more than some entire previous summers.
- Clark County (Las Vegas) reported 187 fatalities, with many victims being elderly residents without air conditioning.
- Nationwide, the CDC logged more than 42,000 heat-related emergency-room visits during the month.
Infrastructure Pushed to the Breaking Point
- Phoenix Sky Harbor cancelled or diverted 187 flights when pavement temperatures exceeded 65°C (149°F).
- Sections of Interstate 10 buckled and cracked under the intense heat.
- Rolling blackouts hit parts of Arizona and Nevada as electricity demand surged 18% above 2024 peaks.
What the Rest of Summer 2025 Holds
NOAA’s latest outlook, issued July 18, 2025, predicts above-average temperatures across 88% of the Lower 48 through September, with the Southwest facing a 90–100% chance of continued extreme heat.
Translation: July and August could be even more dangerous.
Where to Escape the Heat Right Now
While most of the country baked, a few lucky spots stayed remarkably comfortable in June 2025:
- Seattle, Washington – never topped 27.8°C (82°F)
- Portland, Oregon – peaked at 31.1°C (88°F)
- San Francisco, California – highest temperature just 26.1°C (79°F)
For real-time conditions and cooler destinations across the entire United States, check the live weather map at
→ WhatWeather.today – USA Live Weather Map
How to Stay Safe When Temperatures Climb Above 45°C (113°F)
- Never leave children or pets in vehicles — interior temperatures can reach 60°C (140°F) in minutes.
- Drink water before you feel thirsty; dehydration starts long before thirst kicks in.
- Avoid outdoor activity between 10 a.m. and 6 p.m.
- Check on elderly neighbors and relatives — they account for nearly 70% of heat deaths.
The Bigger Picture: A Preview of the New Normal
Dr. Sarah Kapnick, NOAA Chief Scientist, warned during the July 2025 briefing:
“We are now in an era where all-time heat records fall almost every single year. June 2025 wasn’t an anomaly — it was a preview.”
With global temperatures still rising, events like this are becoming the rule, not the exception.
Stay informed, stay cool, and keep checking reliable sources.
For the latest radar, hourly forecasts, heat alerts, and side-by-side comparisons of top weather services across America, visit:
→ WhatWeather.today – Real-Time U.S. Weather Forecasts
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