Arizona’s monsoon season began Sunday, June 15, and Phoenix opened it with passing showers, a small storm chance and more triple-digit heat than relief. Rain moved through parts of the Southwest Valley and Southeast Valley early Monday, and the city still faced about a 20% chance of storms by Monday evening.
The season runs through September 30, and the first day already put the Valley on notice. Scattered thunderstorms were expected to build over the higher elevations of northern and eastern Arizona before drifting toward the Valley later Monday and into the evening, bringing the kind of fast-moving weather that can dump rain in one neighborhood and leave the next one dry.
Captain Ashley Losch said most Valley residents know how quickly storms can move in and out, carrying strong winds, dust, rain and flash flooding. She also warned that the storms can interrupt water, power and gas service. Parts of Arizona were already under flash flood warnings as monsoon weather spread, while an extreme heat warning remained in place for parts of the Grand Canyon.
For Phoenix, the more immediate question is not whether monsoon season has started. It has. The question is how much of the moisture reaches the city before the heat pushes back. Monday’s forecast high was near 108, overnight lows around the Valley were expected to stay in the mid 80s to near 90, and the heat was set to keep building with 110 on Tuesday and 109 on Wednesday.
That leaves the Valley with a mixed start to the season: enough rain to make the kickoff feel real, but not enough to knock down the heat. Phoenix had only a 10% chance of showers on Thursday, with highs around 107, then temperatures were expected to stay around 107 on Friday and near 105 over the weekend. For now, Phoenix Weather means a brief shot at storms, a real flash flood risk in the right places and very little break from the heat.
