Phoenix residents face a notable shift in weather conditions as moisture streams into Arizona from the remnants of Hurricane Odalys, bringing scattered showers, potential thunderstorms, and a significant cooling trend to the Valley. Clouds are arriving Saturday night ahead of the incoming moisture system.
Rain Chances and Storm Timelines for Phoenix
Scattered showers and isolated thunderstorms could develop across central Arizona and the Valley by Sunday afternoon and evening. Rain chances increase further on Monday and Tuesday as another storm system approaches from the west, combining with moisture from Hurricane Polo to elevate the risk of heavy downpours. Early estimates from forecasters indicate that parts of the Valley could accumulate between a half inch and an inch of rain, with higher totals expected in the high terrain north and east of Phoenix.
Flood Watches and Temperature Drops
Flood Watches are active across northern Arizona from Sunday night through Tuesday night, and across southeast Arizona from Monday morning through Tuesday night. Officials urge motorists to avoid driving through flooded roadways and washes, emphasizing the safety rule to turn around rather than attempt crossing high water. As the storm system moves through, Valley high temperatures will drop into the 80s to low 90s on Monday and Tuesday.
Monsoon Season Conclusion and Historical Averages
Drier air is scheduled to return by Wednesday, marking the final official day of the monsoon season. Temperatures are expected to climb back into the upper 90s by the end of the week. Recent climate data highlights a drying trend in the region: the average monsoon rainfall in Phoenix dropped from 2.71 inches for the 1981–2010 period down to 2.43 inches for the 1991–2020 period. Similarly, average yearly rainfall decreased from 8.03 inches to 7.22 inches between the same historical windows. For the current year, Sky Harbor has recorded 2.16 inches of total rainfall to date, which sits 3.13 inches below average, while monsoon rainfall to-date stands at 1.84 inches, or 0.51 inches below average.
Keep reading