Severe Weather History


Hazard archive · 1950 — present

Flash Flood in Maricopa County, Arizona

580

Recorded events

15

Direct deaths

6

Direct injuries

$57.4M

Property damage

Flash Flood in Maricopa County, Arizona: 580 recorded events between 1996 and 2025. The strongest on record measured 2. That places the county #3 nationally and #2 statewide for this hazard.

Decade by decade

Flash Flood in Maricopa County, Arizona: events per decade

Flash Flood in Maricopa County, Arizona: recorded events per decade
Flash Flood in Maricopa County, Arizona: recorded events per decade

Reporting practice changed over time — early decades are undercounted, not calmer.

The busiest decade for flash flood in Maricopa County is the 2020s, when 289 of the county's 580 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.

Within the Maricopa County archive, flash flood makes up 21.1% of all recorded severe weather across 9 hazard types. Nationally the county sits at #3 for this hazard and #2 within Arizona, putting it in the 99.9 percentile of all U.S. counties.

Seasonality

Events by month

4Jan
3Feb
13Mar
0Apr
3May
5Jun
115Jul
212Aug
105Sep
83Oct
35Nov
2Dec

Aug is the peak month for flash flood in Maricopa County with 212 recorded events, while Apr is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.

Significant events

Deadliest on record

DateLocationScaleDeathsInjuriesDamage
Mar 29, 1998SUNFLOWER030$0
Aug 23, 2020TORTILLA FLAT023$10K
Aug 18, 2021CAREFREE020$20K
Aug 14, 2021(GBN)GILA BEND MUNI020$25.0M
Aug 10, 2005NEW RIVER020$300K
Oct 12, 2025LIBERTY010$50K
Sep 26, 2025PARADISE VLY010$200K
Jul 15, 2012WICKENBURG010$0
Source: NOAA/NCEI Storm Events · dates UTC

Most recent

Latest recorded events

DateLocationMagnitudeDamage
Nov 20, 2025NEW RIVER0$0
Nov 20, 2025CAVE CREEK0$30K
Nov 20, 2025WEST CHANDLER0$0
Nov 20, 2025PHOENIX DEER VLY ARP0$20K
Nov 20, 2025FOWLER0$0
Nov 19, 2025GLADDEN0$20K
Nov 19, 2025GLADDEN0$0
Nov 18, 2025BEARDSLEY0$20K
Nov 18, 2025WITTMANN0$0
Nov 18, 2025MATTHIE0$20K
Source: NOAA/NCEI Storm Events · dates UTC · recent entries may be preliminary

Other hazards here

More from Maricopa County

County overview →

From the record

What the reports say

Written by National Weather Service staff at the time of the event · public domain

Quick answers

Frequently asked

How many flash flood events are on record in Maricopa County, Arizona?

580 flash flood events are recorded in Maricopa County between 1996 and 2025, causing 15 direct deaths.

What is the strongest flash flood recorded in Maricopa County?

The strongest flash flood on record in Maricopa County measured 2.

Where does the flash flood data for Maricopa County come from?

All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.

Cite this page

“Flash Flood in Maricopa County, Arizona.” Severe Weather History. severeweatherhistory.com/county/arizona/maricopa-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.


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