Phoenix Weather Alert: Record-Smashing Heat Wave Hits the Valley—Latest Forecast & Safety Tips

Phoenix saw a surprise soaking to open June, snapping a 111-year streak of rain-free June 1sts. Sky Harbor measured 0.24″ Sunday and another 0.07″ early Monday, vaulting this month into the city’s top-10 wettest Junes ever recorded. Some West Valley gauges even topped two inches, turning normally parched washes into rushing streams and trimming local wildfire danger—at least temporarily. Heading back to triple digits After Tuesday’s upper-90s, a classic desert ridge rebuilds. Forecast highs climb to 102 °F Wednesday, 104 °F Thursday and 106-107 °F Friday through Sunday, running several degrees above the June average of 101 °F. Overnight lows will struggle to dip below 80 °F, keeping heat stress elevated around the clock. Why the early-season rain matters • Soil moisture spike: A half-inch of valley rain in early June is rare, delaying the onset of peak wildfire conditions. • Humidity bump: Added moisture will make the upcoming heat feel muggier than a typical dry-heat stretch. • Monsoon preview: Early storms hint at an active pattern once the official monsoon season begins on June 15. Heat safety checklist for the workweek • Hydrate before you dehydrate: Start each morning with at least 16 oz of water and carry a refillable bottle. • Plan outdoor work by 10 a.m. or after sunset; asphalt temperatures can exceed 150 °F in the afternoon. • Never leave kids or pets in parked vehicles—interior temps can soar above 135 °F in minutes. • Know the signs of heat illness: dizziness, rapid pulse, and cessation of sweating signal a medical emergency. Pool chemicals and lightning: hidden storm leftovers The burst of rain diluted residential pool chemistry; test and rebalance chlorine and pH to avoid algae bloom. Though the Valley is drying out, lingering instability could keep a slim (10 %) chance of high-country thunderstorms through Wednesday afternoon, so hikers near Payson and Flagstaff should monitor radar for pop-up cells. Travel impacts I-17 and SR 87 were slick with oil-lifting showers Monday, but pavement has since dried. Expect typical summer congestion returning to construction zones, especially near the Durango Curve and Loop 202 South Mountain merge during evening peak when 105 °F heat shimmers off the roadway. Looking ahead: when will the monsoon ramp up? Long-range outlooks favor a high-pressure dome parking over Four Corners by mid-June, steering Gulf of California moisture northward. That pattern typically sparks Phoenix’s first true monsoon storm between June 25 and July 4. Until then, the metro will bake under clear skies—so keep sunscreen, wide-brimmed hats, and frequent hydration at the top of your daily checklist. Bottom line Record-setting rain gave Phoenix a brief taste of spring, but blazing summer norms return by mid-week. Stay weather-aware, practice heat safety, and prepare for the next act—monsoon 2025.