Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 17, NWS Phoenix, AZ

July 3, 2021Gila County, Maricopa County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 3, 2021, 6:46 PM MST for Gila County, Maricopa County, Arizona. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 3, 2021, 6:46 PM MST (01:46 UTC)
Expired: Jul 3, 2021, 10:45 PM MST
In force: 4 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Gila County, AZ, Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 53 km from the middle of the area, began a volume at 01:48 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 1.8 hours before the alert went out and 70 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 281 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 3054 m above ground
0-6 km bulk shear: 4 kt
0-1 km storm-relative helicity: -30 m²/s²
0-3 km storm-relative helicity: 3 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

307 
WGUS55 KPSR 040146
FFWPSR
AZC007-013-040545-
/O.NEW.KPSR.FF.W.0017.210704T0146Z-210704T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
646 PM MST Sat Jul 3 2021

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  The Bush and Woodbury burn scar in...
  Gila County in east central Arizona...
  Maricopa County in south central Arizona...

* Until 1045 PM MST.

* At 646 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over the Bush and Woodbury Burn Scar. Between 1 and 1.5 
  inches of rain have fallen. Flash flooding is ongoing or expected 
  to begin shortly.

Excessive rainfall over the burn scar will result flow of creeks and 
washes from both the Bush and Woodbury Fire Burn Scars into the Salt 
River and associated lakes.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding in and around the Bush and
           Woodbury Burn Scars.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of areas in and around
           the Bush and Woodbury Burn Scar.

* Some locations that will experience flash flooding include...
  Apache Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3368 11126 3370 11119 3369 11118 3364 11120
      3361 11122 3358 11123 3357 11123 3348 11118
      3349 11133 3357 11138 3364 11134

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

MS

2 follow-up statements

785 
WGUS75 KPSR 040255
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
755 PM MST Sat Jul 3 2021

AZC007-013-040545-
/O.CON.KPSR.FF.W.0017.000000T0000Z-210704T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Maricopa AZ-
755 PM MST Sat Jul 3 2021

...FLASH FLOOD WARNING FOR THE BUSH AND WOODBURY BURN SCAR REMAINS 
IN EFFECT UNTIL 1045 PM MST THIS EVENING FOR GILA AND MARICOPA 
COUNTIES...

At 755 PM MST, Doppler radar indicated 1 to 2 inches of rain had 
fallen over portions of the Bush and Woodbury fire burn scars. 
Creeks which received heavy rainfall drain into the Salt River and 
associated lakes.  Rapid rises of creeks and inflow into lake inlets 
along Salt River lakes could pose a threat to those recreating.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding in and around the Bush and Woodbury Burn
         Scar.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of areas in and around
         the Bush and Woodbury Burn Scar.

Some locations that will experience flash flooding include...
  Apache Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3368 11126 3370 11119 3369 11118 3364 11120
      3361 11122 3358 11123 3357 11123 3348 11118
      3349 11133 3357 11138 3364 11134

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

MS

247 
WGUS75 KPSR 040543
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1043 PM MST Sat Jul 3 2021

AZC007-013-040553-
/O.EXP.KPSR.FF.W.0017.000000T0000Z-210704T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-Maricopa AZ-
1043 PM MST Sat Jul 3 2021

...FLASH FLOOD WARNING FOR THE BUSH AND WOODBURY BURN SCAR WILL 
EXPIRE AT 1045 PM MST THIS EVENING FOR GILA AND MARICOPA COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3368 11126 3370 11119 3369 11118 3364 11120
      3361 11122 3358 11123 3357 11123 3348 11118
      3349 11133 3357 11138 3364 11134

$$

CK

The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 3, 5:11 PM MST	Special Weather Statement	PSR		49 min
Jul 3, 5:20 PM MST	Special Weather Statement	PSR		25 min
Jul 3, 5:29 PM MST	Areal Flood Advisory	PSR	Pinal	3 hr
Jul 3, 5:32 PM MST	Special Weather Statement	PSR	Maricopa	43 min
Jul 3, 5:38 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Jul 3, 5:41 PM MST	Dust Storm Warning	PSR	Maricopa, Pinal	44 min
Jul 3, 5:43 PM MST	Dust Storm Warning	PSR	Maricopa	62 min
Jul 3, 5:56 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Jul 3, 6:05 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Jul 3, 6:10 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Jul 3, 6:20 PM MST	Special Weather Statement	PSR	Maricopa	40 min
Jul 3, 6:23 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila, Maricopa	4 hr
Jul 3, 6:31 PM MST	Special Weather Statement	PSR	Gila	44 min
Jul 3, 6:43 PM MST	Dust Storm Warning	PSR	La Paz, Maricopa, Pinal, Yuma	62 min
Jul 3, 7:13 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Jul 4, 3:09 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Jul 4, 3:43 PM MST	Special Weather Statement	PSR	Gila	32 min
Jul 4, 4:10 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Jul 4, 4:36 PM MST	Special Weather Statement	PSR	Gila	24 min
Jul 4, 4:51 PM MST	Special Weather Statement	PSR	Gila	39 min

Nearby

Flash Flood Warnings in Arizona, 2021 Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.