Triple-digit temperatures for the Inland area return this week, along with the chance of thunderstorms in the mountains and deserts. And while many of us escape the worst of it in air-conditioned homes and offices, others have to brave the heat to get their jobs done.

High temperatures that can reach above 100 are forecast to linger through Monday, July 22 for the Inland valleys of Riverside and San Bernardino counties.

Here’s some tips from those who know: Precautions for outdoor workers; advice on swimming pool water treatment, and what not to do when a car overheats.

Cesar Rodriguez of Liberty Towing in Riverside hooks up a pickup truck for towing in Fontana on Monday, July 15, 2019. Rodriguez says calls for tow trucks for flat tires and overheating always increase on hot days. (Photo by Eric Vilchis, The Press-Enterprise/SCNG)

A Caltrans maintainance crew, one wearing a protective neck covering to ward off the sun, repairs a fence along the 215 Freeway in Riverside. (Courtesy of Caltrans)

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Cesar Rodriguez of Liberty Towing in Riverside gets ready to tow a pickup truck in Fontana on Monday, July 15, 2019. Rodriguez says calls for tow trucks for flat tires and overheating always increase on hot days. (Photo by Eric Vilchis, The Press-Enterprise/SCNG)

A utility worker tries to stay out of the sun as he moves telephone lines to a new pole Friday July 12, 2019 as temperatures in the Inland Empire rise into the triple digits. The worker was moving the lines further from away from Haven Avenue, near Arrow Route, because Haven is planned to be widened in the future. (Photo by Will Lester, Inland Valley Daily Bulletin/SCNG)

Cesar Rodriguez of Liberty Towing in Riverside hooks up a pickup truck for towing in Fontana on Monday, July 15, 2019. Rodriguez says calls for tow trucks for flat tires and overheating always increase on hot days. (Photo by Eric Vilchis, The Press-Enterprise/SCNG)



Utility workers stay out of the sun as they move telephone lines to a new pole Friday July 12, 2019 as temperatures in the Inland Empire rise into the triple digits. The workers were moving the lines further from away from Haven Avenue, near Arrow Route, because Haven is planned to be widened in the future. (Photo by Will Lester, Inland Valley Daily Bulletin/SCNG)

Cesar Rodriguez of Liberty Towing in Riverside takes down some information as he hooks up a pickup truck for towing in Fontana on Monday, July 15, 2019. Rodriguez says calls for tow trucks for flat tires and overheating always increase on hot days. (Photo by Eric Vilchis, The Press-Enterprise/SCNG)

A Caltrans worker, wearing a protective neck covering to ward off the sun, repairs a fence along the 215 Freeway in Riverside. (Courtesy of Caltrans)

Workers work a cell phone tower near Haven and Edison Avenues in Ontario on Monday, July 22, 2019. (Photo by Watchara Phomicinda, The Press-Enterprise/SCNG)

A construction worker cleans the roof with a leaf blower at a new home community in Eastvale on Monday, July 22, 2019. (Photo by Watchara Phomicinda, The Press-Enterprise/SCNG)



White Line Fever

Tow-truck driver Cesar Rodriguez of Liberty Towing in Riverside warns through experience that problems can cascade from hot-weather radiator breakdowns.

“When a car overheats, a lot of people put room-temperature water in it and it cracks the (engine) heads,” Rodriguez said. “And they open the radiator caps” unleashing a rush of steam or water. “I’ve seen a lot of people get burned,” he said.

The AAA has long advised motorists not to remove the radiator cap from a hot engine.

Worn tires that might have made it through a cooler day will blow out from traveling on hot pavement, Rodriguez said. Sometimes drivers with a flat will stop in freeway lanes, and Rodriguez says that’s a dangerous choice.

“I have seen people get killed by that. They need to keep driving and move over” to a safe area, even if that means driving on the tire rim. “Your life is worth more,” he said.

In addition to checking on tire and radiator conditions, the automobile association also recommends checking on battery strength, which can get drained in hot weather.

Everything into the pool

Backyard swimming pools can have bad chemistry during a heat wave, said Ryan Martineau, owner of Aqua Care Pools in Riverside.

“More people are swimming, the water is warmer, and it just eats through chemicals faster,” he said. The balance of chemicals, including chlorine, that are used to control bacteria and algae need more replenishment than in cooler weather, he said.

Martineau said he interviews clients about the size of their pool, whether they have kids and pool parties, and looks to see if there are plants and trees that can shed into the pool — all factors that will go into the treatment along with measuring the pool’s chemical balance.

“Evaporation really affects the pool as well,” he said. “Riverside has really hard water, and when it evaporates it leaves the calcium behind,” he said over the phone recently, as he was working on a pool.

He recommends service once a week. “In the summertime, the focus is algae; in the winter (pool treatment) is more cosmetic,” Martineau said.

When your job puts you in the sun

Caltrans workers do some of their heaviest lifting at night and early morning, when freeway and highway traffic is lighter.

But that’s not always the choice, and that means going out under the sun in protective clothing — hard hat, long-sleeved shirt, full-length pants, safety boots and orange vest or shirt.

Caltrans follows a set of rules designed to keep workers safe from heat exhaustion, spokesman Shane Massoud said recently.

Supervisors make sure workers drink at least one quart of water per hour if temperatures are above 80 degrees; if temperatures are more than 95 degrees, Caltrans workers take a 15-minute break every hour in the shade, which has to be provided by canopies or tarps if not available at the site.

There’s always a safety meeting before work begins, Massoud said, but on hot days supervisors review hot-weather procedures with the crew tell them to be mindful for signs of heat illness, and check for details such as urging use of neck-cover attachments to hard hats, he said.

The emphasis, he said, “is to watch out for each other.”

The forecast

Highs for the Inland valleys in Riverside and San Bernardino counties will range from the high 90s to the low 100s through Monday, July 29 with afternoon and evening thundershowers possible at least through Wednesday, the National Weather Service said.

A familiar summer weather system puts a high pressure zone over the Four Corners, bring moisture from the southeast, and conditions that can generate thunderstorms, especially in the mountains and deserts.

The NWS on Monday afternoon issued a flash flood warning and a flood advisory for the desert area of San Bernardino County in the area of Joshua Tree National Park. The warning and advisory were due to end Monday evening.

Nighttime temperatures for the valleys will be in the high 60s and low 70s.

Mountains in Riverside County will have hotter daytime temperatures for the higher elevations, in the high 80s and mid-90s, compared with the mid-70s to mid-80s for the San Bernardino County mountains.

And both ranges will face possible thunderstorms or showers in the afternoon and evening.