This post examines the intense thunderstorms that swept through the Phoenix metro area on Friday, producing unusually heavy rainfall. The storms prompted flood watches across parts of central and southeastern Arizona and briefly erased the city’s monsoon deficit.
As a meteorologist with three decades of experience, I break down what happened and where the greatest impacts were felt. I also discuss what to watch for this weekend and how this event fits into longer-term monsoon trends.
What the storm delivered to the Valley
The line of severe thunderstorms moved quickly but packed a strong punch. Heavy downpours and localized flooding occurred across the Phoenix metro area.
Many locations reported more than an inch of rain in a short period. Urban drainage and wash systems that are usually dry were overwhelmed.
These storms are characteristic of monsoon dynamics — high instability, abundant moisture, and slow-moving convection. The magnitude of the rainfall in some spots was notable.
Measured rainfall and immediate impacts
Phoenix Sky Harbor Airport recorded 1.64 inches of rain in the event, occurring in roughly 30 minutes. That single storm produced more rainfall at the airport than the rest of the monsoon season had combined to that point.
The rapid accumulation wiped out the city’s monsoon rainfall deficit in a very short window.
County and state meteorologists issued Flood Watches for areas east and southeast of the Valley, including Casa Grande, Apache Junction, Globe, Florence, and Fountain Hills. Southeastern Arizona communities such as Tucson and Safford were also placed under Flood Watches through Saturday evening.
Officials urged caution: flooding could affect rivers, desert washes, city streets, and low-water crossings. Travel was especially hazardous during and immediately after storms.
Short-term outlook and public-safety guidance
While the storms have a rapid, intense nature, they are also highly localized. Some neighborhoods received substantial rainfall while nearby areas saw little.
The remainder of the weekend looks warmer and largely dry. Scattered storms may linger into Sunday.
Forecasts suggest a return to drier conditions next week as high pressure rebuilds over the region. Temperatures are expected to rise again.
Practical safety steps for residents
When Flood Watches are in effect, take simple precautions to reduce risk and travel dangers:
Context: How this storm fits into longer-term monsoon trends
Monsoon rainfall across Phoenix has shown a subtle decline when examined over successive 30-year climate normals. Specifically, average monsoon rainfall decreased from 2.71 inches (1981–2010) to 2.43 inches (1991–2020).
This reflects a shift toward drier conditions over recent decades. That trend influences water management, ecosystem responses, and the frequency of very dry spells between storm clusters.
What to take away
Short, intense storms are part of the monsoon’s variability. They are capable of producing dramatic local flooding and temporarily erasing deficits.
The longer-term signal points toward modest drying in average monsoon totals for Phoenix. Residents should remain vigilant during active weather and respect flood watches and warnings.
Here is the source article for this story: MOST ACCURATE FORECAST: ABC 15 Weather Action Day as severe storms pack punch today