He was running errands when he felt weak and faint.
"Then all of a sudden, heat, it just fixed me just beautifully," he said.
Lewis was able to make it to a nearby restaurant to get water and rest.
The L.A. County Department of Public Health said the combination of triple-digit temperatures and humidity is causing a dangerous mix.
The elderly and the young are always the most vulnerable to heat-related illness, but even young adults can run into trouble in high temperatures.
"Even for very healthy people, it's a time to drink lots of fluids even before you're thirsty, make sure your electrolyte levels are high by drinking sports drinks and really stay inside," said Dr. Alonzo Plough of the L.A. County Department of Public Health.
When dehydration sets in, heat cramps are usually the first sign that you are in trouble. Symptoms include muscle pains and spasms, usually in the stomach, arms or legs.
This can escalate to exhaustion, where you'll see heavy sweating, clammy skin, extreme muscle weakness and headache. If you're suffering from heat stroke, there's no sweating, you have hot, dry skin and a temperature above 103. You will also have a rapid strong pulse.
"Essentially, your body's temperature modulation system has broken down when you're in a heat stroke. That is a life threatening condition and requires immediate medical treatment," Plough said.
Lewis said he learned his lesson, and he's spending the hottest part of his day at a cooling center. It's advice L.A. County health officials hope other people will follow.
"It's a good time to spend the afternoon at the mall or at a movie theater or a library, but really important to stay out of this heat this weekend," Plough said.