The western U.S. remains under dangerous and prolonged heat

Dangerous heat returns to the Southwest

Dangerous heat has returned to the Desert Southwest, with Extreme Heat Warnings covering parts of southeastern California, southern Nevada and northwestern Arizona through Friday. Arizona’s lower deserts are also facing another stretch of potentially dangerous temperatures.

Other western areas are seeing different conditions. Parts of inland Southern California are under heat advisories, while portions of Oregon are dealing with wildfire-smoke air-quality alerts.

High pressure traps the heat

A strong upper-level ridge over the Desert Southwest is driving the current heat. High pressure promotes sinking air that warms as it descends, while generally clearer conditions can allow strong daytime heating.

The National Weather Service expects lower-desert highs in Arizona to reach roughly 109 to 113 degrees through the workweek, several degrees above normal for this time of year. Extreme Heat Warnings remain in effect through Friday.

Southern California faces renewed heat

Parts of inland Southern California are facing another stretch of hot weather. Around Palmdale, afternoon temperatures are forecast near 99 degrees Tuesday, 103 Wednesday and 101 Thursday, while heat advisories cover some inland areas of Southern California.

Conditions farther north are different from the earlier August heat episode. The National Weather Service office in Medford is currently highlighting wildfire-smoke air-quality concerns rather than a widespread extreme-heat warning across the region.

Southern Nevada faces renewed extreme heat

Southern Nevada is facing another round of dangerous heat, with an Extreme Heat Warning in effect through Friday evening. The National Weather Service expects highs of 107 to 110 degrees across many warned areas, with 115 to 118 possible in Death Valley and the lower Colorado River Valley.

Las Vegas is forecast to reach about 109 degrees Tuesday and Wednesday and 110 Thursday. Overnight lows in the mid-to-upper 80s will provide limited relief from the daytime heat.

The Southwest stays hottest longest

The Desert Southwest is again facing significant heat risk this week. Arizona’s lower deserts are expected to reach roughly 109 to 113 degrees, with Major HeatRisk lasting through the workweek and Extreme Heat Warnings continuing through Friday.

Dangerous heat is also affecting parts of the southern Plains and Southeast. Conditions vary sharply by region, making current local forecasts and warnings important for anyone spending extended time outdoors.

Warm nights increase the danger

Daytime highs draw attention, but hot nights can make prolonged heat more dangerous. Homes without air conditioning may remain warm long after sunset.

The body needs cooler periods to recover from daytime exposure. When overnight temperatures stay elevated for several days, older adults and people with health conditions face greater strain and less restful sleep.

Some groups face greater risk

Extreme heat can affect anyone, but certain people need extra protection. Older adults, young children, outdoor workers, athletes, and residents without cooling face higher risks.

People taking some medicines or living with ongoing health conditions may also struggle. Neighbors should check on anyone who lives alone or lacks reliable transportation during prolonged periods of extreme heat.

Little-known fact: Phoenix hit 116 degrees, tying its hottest Aug. 1 on record, first set in 1972.

Outdoor work becomes harder

Construction crews, farmworkers, delivery drivers, and others working outdoors may face repeated exposure during the hottest hours. Shade and water alone may not provide enough protection.

Federal safety guidance recommends frequent rest breaks in cooled or shaded spaces. Employers can also adjust schedules so demanding tasks happen during cooler mornings or evenings whenever possible and practical.

Smoke may block nighttime cooling

Active wildfires are adding smoke to parts of the West during the heat wave. Poor air quality can make opening windows at night an unsafe cooling option.

Smoke also creates added breathing concerns for sensitive residents and outdoor workers. Local air-quality alerts can change quickly throughout the day as winds shift and fires continue burning.

Energy demand rises with temperatures

Air conditioners run longer during extended heat, increasing electricity demand when the grid is already stressed. Utilities may prepare extra generation for late-afternoon peaks.

Residents can lower indoor heat by closing blinds and avoiding major appliance use during hot hours. Any official conservation request should come from local utilities during the most demanding periods locally.

Cars heat up within minutes

Vehicles can become dangerously hot very quickly, even when outside temperatures seem manageable. A cracked window does not provide enough protection during extreme heat.

Children and pets should never remain inside parked cars. Drivers should also check back seats before locking vehicles, keep keys away from children, and look carefully before finally walking away safely.

Simple steps reduce exposure

Drink water regularly, wear lightweight clothing, and limit strenuous activity during the hottest hours. Air-conditioned libraries, malls, and cooling centers can provide safer spaces.

Watch for dizziness, heavy sweating, weakness, confusion, or worsening symptoms. Anyone showing signs of a serious heat emergency needs immediate medical attention, rapid cooling, and help without any unnecessary delay today.

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Relief will arrive unevenly

Relief from the latest western heat will arrive unevenly. Las Vegas is forecast near 109 to 110 degrees through Thursday before temperatures ease to around 103 Friday.

Phoenix is expected to remain hotter for longer, with highs ranging from roughly 107 to 113 degrees through Saturday. Residents should follow local forecasts because warning periods and heat intensity vary widely across the region.

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What do you think about the western U.S. remaining under dangerous and prolonged heat? Share your thoughts in the comments.

This slideshow was made with AI assistance and human editing.

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