Big weather shift for Arizona this weekend
PHOENIX – A dramatic cooldown and weekend rain are on the horizon for central Arizona, marking a significant shift in weather as tropical moisture surges north. First Alert Weather Days have been officially declared for Sunday and Monday, as the Valley of the Sun prepares for temperatures well below average and the potential for meaningful rainfall.
Thursday and Friday: Warmth before the wave
Today’s high in Phoenix is expected to reach around 100°F (38°C), already pushing the limits of seasonal norms. By Friday, thermometers may climb to 104°F (40°C), notably warmer than the average 98°F (37°C) typical for late May in Maricopa County. Cloud cover and a low-pressure system off the Pacific coast are contributing to the temporary heat and hazy skies.
Alongside the heat, the Arizona Department of Environmental Quality has issued an Ozone High Pollution Advisory for both days, warning of air quality levels that may exceed federal health standards. Outdoor activity is not recommended for sensitive groups.
Saturday to Monday: Tropical moisture fuels rain chance
By Saturday, the slow-moving low-pressure system receives an injection of tropical moisture, courtesy of Tropical Depression One-E. The system is strengthening and could soon be named Tropical Storm Alvin, traveling northward along the Baja Peninsula.
Though expected to dissipate near Cabo San Lucas by Sunday, its remnants will be drawn inland, dragging moisture into southern Arizona. This setup paves the way for storm activity in Phoenix and surrounding regions, with the best chances for rain arriving Sunday afternoon into Monday morning.
Sunday highs will drop to the upper 80s°F (around 31°C), providing a welcome relief after days of triple-digit heat. Rainfall totals are uncertain, but early forecasts suggest up to half an inch could fall across the Valley, an excellent start to June and rare for this time of year.
Early next week: Continued relief
Following the Monday showers, drying trends will resume across the region. However, temperatures will remain below seasonal averages through Wednesday, offering several days of reprieve from the early summer heat.
