Originally Published: 15 JUL 23 09:06 ET

Updated: 15 JUL 23 16:07 ET

By Elizabeth Wolfe and Caitlin Kaiser, CNN

(CNN) — More than 85 million people remained under heat alerts Saturday as the weekslong heat wave continues and intensifies in the Southwest.

Dangerously high temperatures will continue to plague the Western United States throughout the weekend, with temperatures growing hotter in the South early next week.

“Daytime highs will routinely range between 10-20F above normal, equating to daytime temperatures approaching the century mark in the interior Northwest, between 100-110F in central and southern California, and 115-120F+ in the high desert of southern California, southern Nevada, and Arizona,” according to the Weather Prediction Center.

More than 100 temperature records are possible through Monday across the West and South.

Death Valley, California, could top 130 degrees on Sunday. That’s happened just five times in more than 110 years of record

Phoenix temperatures have reached 110 degrees on consecutive days, and the streak should continue through at least Wednesday.

In Southern California, the Riverside County Fire Department is battling three wildfires that started Friday, including the Rabbit Fire. It grew from 20 acres to 4,500 acres and was 5% contained Saturday, Cal Fire said.

Meanwhile, sultry conditions will persist in the south-central US and in South Florida. Daytime highs in the 90s to low 100s with oppressive humidity levels will allow heat indices to range frequently between 105-110F each afternoon.

A heat advisory is in place from Texas to Alabama but does not include Georgia or most of Florida. The high in Houston is forecast for 100 degrees on Saturday. It could reach 96 in New Orleans and Jackson, Mississippi. Atlanta is expected to reach only a relatively mild 92.

And wildfire smoke from Canada will move into the Northern Plains and Midwest over the weekend and into early next week.

Concern about power outages from increased demand arose in the Southwest. And some venues planned to close early or cancel events, including the Sacramanto (California) Zoo and the Desert Botanical Garden in Phoenix.

Arizona and Texas endure weekslong heat streaks

Alerts for dangerous heat levels have been posted in areas of Arizona and Texas for more than 30 days in a row as a long-lasting heat wave has settled over parts of the West and South since mid-June.

Temperatures have failed to drop below 90 in the Phoenix area since Monday, a trend that could be deadly for those without air conditioning if they are unable to cool and recover their bodies overnight.

In Texas, El Paso broke its own high temperature streak record on Thursday after experiencing 28 consecutive days above 100 degrees, the weather service tweeted.

That streak will likely extend well beyond 30 days as El Paso is expected to see temperatures of at least 103 degrees through the middle of next week.

Elsewhere, much of Texas’ eastern half saw heat indices – what the combined humidity and temperature feels like – between 110 and 115 degrees on Thursday.

Widespread temperatures of 100 to 108 were seen across much of the state Thursday, including temperatures of 107 in Austin and Del Rio. The North Texas city of Wichita Falls broke a daily record of 110 degrees with a heat index as high as 118 degrees.

The dangers of brutally high heat

As the climate crisis ratchets temperatures higher and higher, scientists have warned there’s a growing likelihood that 2023 could be the Earth’s hottest year on record.

Heat kills more Americans than any other form of severe weather, including flooding, hurricanes or extreme cold, according to National Weather Service data.

Communities across the globe are already feeling the devastation of these extreme temperatures, including one Texas county that reported at least 11 heat-related deaths during last month’s heat wave. In Mexico, at least 112 people have died from extreme heat exposure since March.

While our bodies try to regulate their own temperature, extreme heat can make it hard for the body to cool down, and added humidity can make that struggle even worse.

When the body becomes unable to cool itself, illnesses such as heat exhaustion or heat stroke – which can be fatal – can set in.

The risks of heat exposure are particularly high for people experiencing homelessness, outdoor workers, low-income families, communities of color and the elderly.

To stay safe in sweltering temperatures, experts recommend hydrating regularly, finding a cool or air-conditioned place and avoiding outside activities, particularly during the hottest times of the day.

People should watch for signs of heat exhaustion or other illnesses, which include light-headedness, nausea, headache or confusion.