It's 102 degrees in Arizona, but it's officially too cold to swim. Here's why
Karina Bland - Arizona Republic
https://i.imgur.com/oKKLkEu.jpg
“Bring your swimsuit,” my friend Marian said when she invited me for lunch at her house this week.
I tucked it in my purse, but we didn’t end up going swimming. Even though it was 102 degrees outside. Even though the water temperature was 80. We decided it was too cold.
Wait, what?
I know, I know. To many, that sounds like a lovely time to get in the pool. But if you’ve lived in the Phoenix area for any length of time – Marian and I both moved here in 1978 – well, you know 102 in September is downright chilly for swimming.
It might be an Arizona thing. Out-of-town visitors seem to have no problem jumping into pools at resorts this time of year.
Generally, pool season here starts in May and runs through early September. It’s stretching a little longer this year since it’s been hotter, and everyone is spending more time at home.
But as hot as it is outside, we know nighttime temperatures have dropped. Arizonans know the air is so dry that water evaporates quickly. (It really is a dry heat.) That's why older houses have swamp coolers — they work!
Evaporation is to blame, too, for why we get chilled when we get out of the pool, even if it’s 102. When wet skin is exposed to dry air, the water evaporates immediately. Brrrr.
That doesn’t happen in, say, Florida, where it’s humid.
Maybe we’re wimps. Maybe we’ve acclimated to the desert climate.
“They say your blood thins out, so we can’t handle the cold as well as a hearty Minnesotan,” said Brentt Narveson, who has owned B & B Pools in Tempe for 39 years.
His business slows down noticeably this time of year.
It’s likely a matter of perception, said Robert Wang, an associate professor in Arizona State University’s School for Engineering of Matter, Transport and Energy.
Thermal perception is the temperature “felt” by the body, regardless of what the thermometer reads, Wang said. It varies from person to person, which explains why couples argue about where to set the thermostat.
So if it's a matter of perception, maybe our blood really does thin out.
But not for Wang. Even though he's lived here since 2011, he said he's still swimming and likely will through the end of the month, while I’m deflating floats and washing pool towels one last time, and hanging up foam noodles.
Until next year, when, we can be certain, it will again be officially too hot.
