2025 Monsoon Season is Notable
A powerful storm slammed Phoenix and much of Arizona on Friday, September 26, 2025, unleashing record-breaking rainfall that led to dangerous flash floods, widespread power outages, and major disruptions across the region. The deluge was a dramatic climax to an already active 2025 monsoon season.
What Caused the Record-Breaking Phoenix Storm? ⛈️
The historic downpour was fueled by a deep plume of tropical moisture that surged into Arizona. This atmospheric river was pulled into the state by a strong low-pressure system off the California coast. This combination created highly unstable conditions perfect for slow-moving thunderstorms that produced an incredible amount of rain, leading directly to the Phoenix flood event.
2025 Monsoon: A Season of Extremes from Haboobs to Floods
This year’s monsoon has been particularly memorable, especially when compared to weaker, drier seasons in recent memory. The 2025 monsoon will be remembered for its extremes: just weeks before this record rainfall, Phoenix was engulfed by two massive haboobs (dust storms) that highlighted the season’s power. Friday’s storm, however, brought the season’s impact to a new level with widespread, significant flooding, a phenomenon that has been less common in recent years.
Phoenix Shatters Daily Rainfall Record
Official numbers confirm the historic nature of the storm.
- Phoenix Sky Harbor Airport recorded a final total of 1.64 inches of rain.
- This shattered the old record for September 26th of 0.42 inches, set back in 1984.
- The rainfall from this single day was more than the city typically sees in an entire summer monsoon season.
Hardest-Hit Areas: Where Did the Most Rain Fall?
While the official record was set at the airport, rainfall totals varied across the state, with some areas seeing even more extreme amounts.
- Fountain Hills (Adero Canyon): 3.46 inches
- Miami/Globe Area: This region was severely impacted by flash flooding after receiving 2 to 4 inches of rain over two days, causing destructive damage.
- Other Valley Totals: Areas like the Phoenix Mountains Preserve (1.65 inches) and Arcadia (1.22 inches) also saw significant rainfall.
Widespread Damage and Emergency Response Across Arizona
The impact of the storm was severe, prompting a large-scale emergency response.
- Water Rescues: Dozens of drivers were rescued from vehicles trapped in fast-moving floodwaters.
- Transportation Chaos: Phoenix Sky Harbor Airport experienced a ground stop and hundreds of flight delays. Major freeways and city streets were closed, causing traffic gridlock.
- Power Outages: At its peak, tens of thousands of Arizona residents were left without electricity.
- Closures: The intense weather forced the Arizona State Fair to close for the evening.
How This Storm Ranks & The Future of Phoenix Monsoons
While historic for the date, the 1.64 inches of rain from this event places it among the top-tier monsoon storms but not at the very top of Phoenix’s all-time list. For perspective, it falls well short of the city’s single-day record of 3.29 inches set on September 8, 2014. However, its widespread impact and the sheer volume of water that fell in a short period make it one of the most significant and disruptive monsoon events of the last decade.
Looking ahead, climate experts warn that storms like this may become more common. While overall monsoon rainfall could potentially decrease or become more erratic from year to year, climate change is expected to make the storms that do occur more intense. A warmer atmosphere can hold more moisture, leading to the potential for heavier downpours and more extreme flash flooding events in the future. Experts suggest that the future of the Phoenix monsoon may be a pattern of “drought interrupted by deluge,” making water management and flood preparedness increasingly critical for the region.
