Just when the thick of the summer hits, and you start to feel comfortable complaining about the heat, you're reminded just how much worse it could be. As numerous outlets have reported in recent days (including The Telegraph and USA Today), there's a mercury-raising natural phenomenon occurring in the Middle East right now, and it's putting a big strain on energy and water supplies. Basically, the Middle East "Heat Dome" has Iran facing record temperatures, and it's a very different kind of animal than what we usually have to deal with in the United States.
Just how bad is it? According to The Washington Post, temperatures in the Iranian city of Bandar Mahshahr, the heat index rose to 74 degrees Celsius, or a staggering 165 degrees Fahrenheit. The heat index isn't just a measure of raw temperature, to be clear — it also factors in humidity, to determine how hot the temperature actually feels to a person, and what the practical effect is on their body.
It's a figure that really leaps off the page — even just imagining it is damn near enough to make your forehead glisten. According to The Telegraph, it's believed to be the second-hottest urban environment on record, trailing an unthinkable heat index of 178 degrees Fahrenheit in Saudi Arabia in 2003. AccuWeather meteorologist Anthony Sagliani described it as "one of the most incredible temperature observations" he's ever seen, as well as "one of the most extreme readings ever in the world."
So, how does it measure up to the worst of the worst heat index ratings we've dealt with stateside? Simply put, it's hard to find instances that hold a candle to what they're dealing with in Iran, but there is one example from our shores that sticks out: the highest-ever recorded temperature on U.S. soil, according to LiveScience, came back on July 10, 1913, in California's bone-dry Death Valley. It's believed to have clocked in at 134 degrees Fahrenheit, which would be the highest recorded air temperature in the entire world.
Having traveled through Death Valley in the summer before, I can add some personal (albeit anecdotal) confirmation: it is indeed very hot, and very dry there. The idea that Death Valley's air temperature could compete even with the sweltering climates of the Middle East is no great shock.
But the heat index is the more relevant measure than air temperature, for these purposes. Sadly, it wasn't conceived of until the late 1970s, and as The Washington Post detailed in describing Iran's current woes, it actually only goes so high — the Bandar Mahshahr results are quite literally off-the-charts, and that's also true of the Death Valley record.
However, given the commonly intense dryness of the California desert, we can probably make some safe assumptions. Namely, that the relative humidity levels would be low enough that it wouldn't feel nearly as grueling as this humidity-racked Iranian city does now.
Basically, at the time of this writing, Death Valley is running an air temperature of 96 degrees Fahrenheit, with a dew point — the temperature at which water in the air condenses into liquid, rather than remaining vapor — of 49 degrees. Comparatively, the air temperature in Bandar Mahshahr is only 115 degrees, but the additional influence of the humidity is what makes it so horrifying; the city's "dew point" was 90 degrees on Friday, which is topped only by a 95-degree dew point in that aforementioned Saudi Arabian heat wave in 2003. It's that staggering humidity that makes the difference, making a 115-degree day feel like 165.
Obviously, it's not a contest — at least not beyond the world-record trackers who care about air temperature vs. heat index — but it's useful historical perspective on just how oppressive the climate in Iran is feeling right now.