Shade is pretty cool.

And with the hottest stretch of South Florida's summer quickly approaching, it's going to be in high demand for those venturing from air conditioning.

Shade doesn't actually make temperatures cooler. Rather, being in direct sunlight and solar radiation makes the air feel 10 to 15 degrees warmer than it actually is, said Jim Lushine, a retired weather service meteorologist.

"So, conversely, it would feel that much cooler in the shade," he said.

Similarly, when the ocean breeze comes up, temperatures will feel 4 to 5 degrees cooler, particularly if you've been sweating.

And if you're looking for yet another means to buffer the outside heat, find some grass. It will feel a few degrees cooler than the heat rising off of pavement, Lushine said.

To capture the actual outside air temperature, the National Weather Service places its official thermometers in a shady grassy area. The main weather station gauges are placed at the region's three main airports, in Miami, Fort Lauderdale and West Palm Beach.

If the thermometer were placed in the sun, it would heat up from the solar radiation, "and you would be measuring the temperature of the thermometer itself instead of the air temperature," said Lushine.

From mid-July through mid-August, the average high temperature is about 91 degrees and the average low is about 79, the region's most sweltering period. And temperatures this summer are predicted to be slightly above normal, the weather service said.

Lushine noted that because of all the concrete in South Florida, low temperatures rarely drop below 70 degrees. For instance, he noted that 30 of the 31 daily low temperature records in West Palm Beach were in the 60s and occurred prior to 1944, when the region wasn't as built up.

"Low temperatures have been rising since the early 1900s," he said. "The reason is most likely the heat island effect, where increased urbanization has led to higher temperatures."

What really makes outside readings feel steamy hot is the humidity, as the heat index, or "feels-like" temperatures, frequently top 100 degrees throughout the summer.

"Humidity slows down the body's cooling mechanism," said weather meteorologist Steven Ippoliti. "You can't evaporate sweat off the body, and that's what makes you feel hotter."

Harriet Ziringer, of Boca Raton, said she loves the heat and rarely seeks shade.

"I love it when the sun's burning the back of my legs," she said. "It's one of he best things about living in South Florida."

On the other hand, she said, if humidity levels are high, "shade doesn't help you, you're just as hot. Then, you need to seek the car for air conditioning."

kkaye@tribune.com or 954-572-2085.