KSL Investigates: How hot do the various parade-watching surfaces get?
Jul 22, 2023, 10:05 PM | Updated: Jul 24, 2023, 1:32 pm
COTTONWOOD HEIGHTS, Utah — At Hokulia in Cottonwood Heights, folks are trying to beat the heat with a little sugary-syrup-covered coolness.
Kaylynn Mitchell was running the ice-shaving machine as, she says, a steady line of customers have been showing up.
The snow cones help, but customer Ellen Chapman still described the weather on Saturday as “miserable.”
The mercury measuring the air temperature inched above the 100-degree mark by lunchtime. But ask any barefooted pooch pounding the pavement: they can tell you the air is not the whole story.
For as hot as the air may feel, it pales in comparison to the sun-soaked ground.
We all know from grade school that dark stuff gets hotter than light stuff. And we all know from common sense that shade is less hot than being in direct sunlight. But just how much of a difference does that atmospheric science play on a day like today?
The KSL Investigators put it to the test.
According to the National Institute for Standards and Technology, human skin can sustain a first-degree burn at 118 degrees, and second-degree burns can occur when touching a 131 degree-surface.

The National Institute for Standards and Technology infographic. (National Institute for Standards and Technology)
Using a thermometer, black asphalt at 3 p.m. beat that benchmark. We found it to be 143 degrees.
A few steps away, white concrete was almost 15 degrees cooler, though, at 130 degrees, it was still hot enough to do damage.
The grass next to the same intersection was significantly cooler. It registered at a mere 103 – slightly cooler than the air temperature, which was 106 degrees.
We also tested a tiny patch of shade being cast by the streetlight above. The black asphalt in the shade was 127 degrees. That’s 16 degrees cooler than the asphalt inches away in the sun.
It’s much cooler but not cold by any stretch of the imagination.
What is cold: shaved ice! But whatever you do, don’t eat slowly on a day like today, warns Hokulia customer Braiden Meikel.
“These will probably just melt in like the next 5 seconds,” he said.
According to the National Weather Service, Salt Lake City hit 106 degrees on Saturday, breaking the previous high temperature for July 22.