You’ve felt the heat before, but this weekend, Phoenix is set to crank it up to extremes. Forecasts show temperatures climbing to a scorching 113°F by Sunday, with the heat index reaching Moderate Risk levels—a red flag warning for the elderly, outdoor workers, and anyone without air conditioning. This is more than discomfort—it’s the kind of heat that can knock out power, overheat your body, and make even a quick walk outside feel like stepping into an oven.
From Tuesday through Monday, the Valley of the Sun will see a relentless climb in temperature, with each day getting hotter and nighttime lows staying disturbingly warm, in the upper 80s. The body never gets a chance to cool down, and that makes these kinds of heatwaves especially dangerous.
What’s Actually Happening?
A powerful ridge of high pressure is settling over Arizona, effectively trapping hot, dry air in place. While Phoenix is no stranger to summer heat, the timing and intensity of this wave are raising concerns—especially for sensitive populations and essential workers.
By Sunday, temperatures are expected to top out at 113°F, and could reach 114°F by Monday. At those levels, even short exposure outdoors can result in heat exhaustion or heat stroke, particularly if you’re not staying hydrated or taking frequent breaks.
Adding to the concern is what forecasters call a HeatRisk Level 2—Moderate, a warning tier indicating the kind of weather that can lead to increased hospital visits, power grid strain, and elevated mortality for vulnerable people.
Why This Is a Big Deal
Most people underestimate what this kind of dry heat can do—especially when it doesn’t cool down overnight. When low temperatures stay above 85–88°F, your body can’t fully recover, even while sleeping. This can lead to persistent dehydration, sleep disruption, and high stress on your heart and respiratory system.
For the city’s large outdoor workforce—from landscapers to construction crews—the risks are even higher. With ground temperatures near 150°F, even light outdoor activity can become dangerous fast. Add in the possibility of power outages from overworked AC units, and you have a city on the edge of a true heat emergency.
What You Can Expect Each Day
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Tuesday – Wednesday: Highs between 103–104°F, with clear skies and relatively tolerable humidity—but still not safe for prolonged exposure.
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Thursday – Saturday: Temperatures jump to 107–108°F by day, and overnight lows remain in the 83–85°F range. This is where the real danger begins to build.
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Sunday: The big spike. 113°F projected high, with a heat index well into the Moderate Risk zone. Nighttime low: 88°F.
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Monday: No relief. Temperatures may touch 114°F, continuing the oppressive streak.
How to Protect Yourself and Others
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Avoid outdoor activity between noon and 6 PM. Early morning and late evening are safer.
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Hydrate frequently—even if you’re not thirsty. Add electrolytes when possible.
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Wear long, loose, light-colored clothing and wide-brimmed hats.
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Check in on neighbors, especially seniors and those without AC.
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Don’t rely on fans alone—they’re not effective once temps exceed 95°F.
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Know your cooling centers—Phoenix has opened public spots for anyone needing refuge from the heat.
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Never leave children or pets in parked cars, even for a minute. Internal temps can skyrocket past 130°F in minutes.
Final Word
Phoenix is no stranger to high heat—but what’s coming this weekend isn’t ordinary. With temperatures soaring above 110°F and barely dipping overnight, the risk of serious heat-related illness is real. Whether you’re working outdoors or just trying to stay cool at home, preparation is your best defense.
