Humidity Makes it Tough to Break a Sweat

By SOLOMON MOORE

Sept. 5, 1997 12 AM PT

TIMES STAFF WRITER

The burning question: Why is it so hot? The simple answer: Because it’s summer in Southern California.

But actually it’s not as hot as you think.

Sure, your makeup is dripping off your face and your car is a crucible. Meteorologists say high temperatures coupled with relative humidity make up the heat index, also known as the misery meter.

Humidity is basically water vapor, said WeatherData meteorologist Wes Etheredge, and that is what causes the air to feel heavy and, above all, hot.

Temperatures Thursday ranged from 100 degrees in Burbank to 106 degrees in Van Nuys--but it felt like it was 104 and 112 degrees respectively.

Dr. Sam Fink, a specialist in adult medicine at Encino-Tarzana Regional Medical Center, said it felt hotter Thursday because the body is less able to regulate itself in humid heat.

Usually the body cools itself off by sweating, but “the humidity makes it harder to sweat and get rid of fluids,” Fink said.

That makes this weather particularly dangerous for the elderly and infirm, Fink said. He advised older people to stay indoors and drink lots of fluids.

“They can easily become dehydrated, and they wouldn’t even know it because the first symptom of dehydration is confusion,” he said. “If people have elderly relatives, make sure to check on them.”

Los Angeles’ desert origins combine with the cool Pacific Ocean, which sheds little water vapor, to make the region an extraordinarily dry place. But earlier this week moist air blew in from the Gulf of California and the South Pacific and steamed the San Fernando Valley.

“That’s why you saw thunderstorms over the Southland mountains and rain over the deserts of California and Nevada,” said Etheredge. Humidity in some areas in the Valley reached 70%, and Thursday evening the National Weather Service announced that thunderstorms could form over the Antelope Valley, where it rained Wednesday.

However, most San Fernando Valley residents did not enjoy the grace of rain and had to fight back however they could or flee into air-conditioned malls, cars and movie theaters. And when there were no air conditioners, there were fans.

“I’ve been carrying this fan for about a week,” said Keith Fraser, 46, a Pierce College student. Fraser said he had taken it from class to class since the weather heated up. “I’ve also got an extension cord in my bag.”

Fraser and everyone else in Los Angeles who cranked up fans and air conditioners helped break an electricity consumption record, according to Department of Water and Power officials. DWP customers used 5,520 megawatts Thursday, surpassing the 5,436 megawatts used by customers on Aug. 6, officials said.

Moses Pruch, 33, a hot dog vendor outside Van Nuys Courthouse, said business was down.

“People would rather eat inside with air conditioning,” he said. “It’s too hot to cook--actually I don’t need to cook, I can just lay [the hot dogs] on the ground.”

Joe Wortman, 60, and his friend Edie Metysek walked away from the courthouse, hiding under a large umbrella. Metysek said the weather reminded her of her relatively muggy home state of Indiana, but her experience with humidity didn’t make Thursday’s weather any easier to bear.

“You don’t get used to it,” she said. “You just have to accept it.”

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The Agony Index

High air temperature coupled with high humidity can make it feel hotter than it really is. The heat index on Thursday was 112 in Vany Nuys and 104 in Burbank

*25, *30, *35 *40 *45 *50 *55 *60 *65 *70

**125: ***0 ***0 ***0 ***0 ***0 ***0 ***0 ***0 ***0 ***0

**120: ***139 ***148 ***0 ***0 ***0 ***0 ***0 ***0 ***0 ***0

**115: ***127 ***135 ***143 ***151 ***0 ***0 ***0 ***0/0/0

**110: ***117 ***123 ***130 ***137 ***143 ***150 ***0 ***0 ***0 ***0

**105: ***109 ***113 ***118 ***123 ***129 ***135 ***142 ***149 ***0 ***0

**100: ***101 ***104 ***107 ***110 ***115 ***120 ***125 ***132 ***138 ***144

**95: ***94 ***96 ***98 ***101 ***104 ***107 ***110 ***114 ***119 ***124

**90: ***88 ***90 ***91 ***93 ***95 ***98 ***98 ***100 ***102 ***105

**85: ***83 ***84 ***85 ***86 ***87 ***88 ***89 ***90 ***91 ***93

**80: ***77 ***78 ***79 ***79 ***80 ***81 ***81 ***82 ***83 ***85

**75: ***72 ***73 ***73 ***74 ***74 ***75 ***75 ***76 ***76 ***77