(CNN) — Miami tied its all-time high temperature of 100 degrees Fahrenheit on Tuesday, amid a sprawling heat wave that is affecting areas from Texas to the Southeast. The heat wave, caused by a stalled-out heat dome, continues on Wednesday.
Yes, it’s significant that Miami tied its all-time record. It’s another example of the extreme warming trend caused by climate pollution. But perhaps what’s more surprising is how relatively cool the record is in Miami — a city with a reputation for being hot.
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As Miami hit 100 degrees on Tuesday, parts of Oklahoma saw high temperatures soar well past that, with Kingfisher reaching 112 degrees, a record high there for the date. The all-time hottest temperature on record anywhere in Florida is 109 degrees. Oklahoma’s is 120 degrees. Minnesota’s is 115 degrees.
So what’s up with Florida?
The relatively low all-time record in Miami is tied to its proximity to the ocean and the city’s typically high levels of humidity. It is more difficult for the sun’s energy to heat very humid air to extreme levels than it is to raise the temperature of dry air. A lot of the solar energy goes into evaporating the moisture in the air, so in drier climates, more of the Sun’s energy can go directly into heating the air.
This is part of the reason the hottest locations in the US are in the desert Southwest, rather than in the humid Southeast.
Still, Miami — and the rest of the Southeast — has been experiencing a sharp increase in extreme heat in recent years, including dangerous combinations of heat and humidity that can cause people to succumb to heat illness.
Miami now has 44 more days with temperatures above normal during the summer months compared to the city’s summer climate during the 1970s, according to the nonprofit climate research and communications group Climate Central.
For the summer months of June, July and August, the city has warmed by 2.6 degrees on average, Climate Central found. The city has seen a huge jump in annual days of dangerously humid heat, going from 50 such days in the 1970s to 117 days in the 2016 to 2025 period, Climate Central researchers found.
They attributed a significant proportion of today’s dangerous heat days — 80 days — to human-caused climate change from burning fossil fuels. Tuesday was a good example of a day with dangerously high levels of heat and humidity, as the heat index, which measures how the air feels to the human body, soared as high as 107 degrees.
Miami is forecast to be unusually hot once again on Wednesday, with heat advisories covering all of the Florida Peninsula, with the exception of the Florida Keys, and a forecast high temperature in the mid-to-upper 90s in the city.
The-CNN-Wire
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