Rare Halloween Rain and Flood Watches Impact Arizona Storm Weekend

Phoenix Rain Disrupts Halloween Weekend as Flood Watches Blanket Arizona

A fall storm drenched Arizona over the Halloween weekend, marking the first measurable holiday rainfall in the region since 1987. abc15.com reported that Flood Watches remained active through Sunday across much of Arizona, including the Phoenix metro area.

The storm impacted trick-or-treating plans across the Valley as rain chances ramped up on Saturday night. Sunday brought more widespread and soaking precipitation, prompting local forecasters to declare Sunday an ABC15 Weather Action Day.

Storm Brings Rain Totals and Cooler Temperatures to Region

Weather tracking across the region showed moisture accumulation. The Valley could see 1 to 2 inches of rain through Sunday, with 2 to 3 inches in parts of the high country.

Global Incident Tracker recorded the ongoing weather event as a minor flood incident on Saturday, October 31, 2026, at 23:52 UTC via GNEWS monitoring. Safety guidelines accompanying such events emphasize that flash floods in urban areas can rise within minutes because sealed surfaces stop absorption.

The storm also delivered a dose of cool air. Sunday temperatures dropped into the low 70s, which is about 10 degrees below normal for this time of year. Meteorological projections indicate that the storms are expected to diminish by Monday, clearing the way for drier weather for the first week of November.

Historical Context of Arizona Rainfall

The last time it rained on Halloween was in 1987 with 0.13 inches.

Official climate baselines for Phoenix point toward a drying trend. Official rainfall metrics for Sky Harbor indicate a total of 3.24 inches for the year to date (-2.67 inches from average). Meanwhile, the 2026 monsoon season closed with 2.46 inches of official rainfall (+0.03 inches from average).

Residents seeking detailed, localized precipitation data can consult official updates via the National Weather Service rainfall reports to monitor watershed levels and localized storm runoff.

More on this story: Phoenix Faces Flash Flood Risk With Heavy Weekend Rain · Southern California Storm May Bring First Rainy Halloween Since 2014

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