Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 109, NWS Phoenix, AZ

July 29, 2021Gila County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 29, 2021, 3:56 PM MST for Gila County, Arizona. It was in force for 4 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 29, 2021, 3:56 PM MST (22:56 UTC)
Expired: Jul 29, 2021, 7:32 PM MST
In force: 4 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Gila County, AZ

The radar

The Phoenix radar (KIWA), 82 km from the middle of the area, began a volume at 22:59 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.

What was reported inside it

Time	Report	Where	Remark
Jul 29, 6:15 PM MST	FLASH FLOOD	12 Nnw Claypool, AZ	* DELAYED REPORT * USGS STREAMGAUGE #09498400 PINAL CREEK AT INSPIRATION DAM NEAR GLOBE MEASURED AN APPROXIMATELY 4.25 FT. INCREASE IN A 15 MINUTE PERIOD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 10.9 hours before the alert went out and 103 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: 371 J/kg
Mixed-layer CIN: -231 J/kg
Mixed-layer LCL: 2650 m above ground
0-6 km bulk shear: 4 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 5 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

261 
WGUS55 KPSR 292256
FFWPSR
AZC007-300400-
/O.NEW.KPSR.FF.W.0109.210729T2256Z-210730T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
356 PM MST Thu Jul 29 2021

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  Gila County in east central Arizona...

* Until 900 PM MST.

* At 356 PM MST, Doppler radar and automated rain gauges indicated 
  heavy rain across the warned area as well as upstream near Globe 
  and Miami and over the Telegraph Fire Burn Scar. Between 1 and 2 
  inches of rain have fallen. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar and automated gauges.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  mainly rural areas of Gila County including Pinal Creek

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3354 11090 3358 11093 3362 11098 3365 11097
      3366 11093 3364 11092 3365 11090 3368 11085
      3369 11083 3365 11078 3363 11076

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

$$

MS

1 follow-up statement

823 
WGUS75 KPSR 300232
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
732 PM MST Thu Jul 29 2021

AZC007-300242-
/O.CAN.KPSR.FF.W.0109.000000T0000Z-210730T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
732 PM MST Thu Jul 29 2021

...FLASH FLOOD WARNING IS CANCELLED FOR GILA COUNTY...

Flood waters have receded and the heavy rain has ended. Flooding is 
no longer expected to pose a threat. Please continue to heed 
remaining road closures.

LAT...LON 3354 11090 3358 11093 3362 11098 3365 11097
      3366 11093 3364 11092 3365 11090 3368 11085
      3369 11083 3365 11078 3363 11076

$$

Hirsch

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 12:56 PM MST	Special Weather Statement	PSR	Maricopa	49 min
Jul 29, 1:14 PM MST	Special Weather Statement	PSR		46 min
Jul 29, 1:22 PM MST	Special Weather Statement	PSR	Yuma	38 min
Jul 29, 1:24 PM MST	Special Weather Statement	PSR	Gila	51 min
Jul 29, 1:26 PM MST	Flash Flood Watch	PSR	La Paz, Maricopa, Yuma	40 hr
Jul 29, 1:33 PM MST	Special Weather Statement	PSR	Gila	42 min
Jul 29, 1:35 PM MST	Areal Flood Advisory	PSR	Maricopa	22 min
Jul 29, 1:36 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	6 hr
Jul 29, 1:42 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	48 min
Jul 29, 1:57 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Jul 29, 1:58 PM MST	Severe Thunderstorm Warning	PSR	Gila, Pinal	47 min
Jul 29, 2:07 PM MST	Special Weather Statement	PSR		53 min
Jul 29, 2:11 PM MST	Special Weather Statement	PSR	Yuma	49 min
Jul 29, 2:25 PM MST	Areal Flood Advisory	PSR	La Paz, Maricopa	3 hr
Jul 29, 2:32 PM MST	Special Weather Statement	PSR	Yuma	43 min
Jul 29, 2:35 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Jul 29, 2:44 PM MST	Special Weather Statement	PSR	Gila	46 min
Jul 29, 3:00 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	4 hr
Jul 29, 3:04 PM MST	Special Weather Statement	PSR	La Paz	41 min
Jul 29, 3:17 PM MST	Flash Flood Warning EmergencyCatastrophic damage threat	PSR	Gila	3 hr
Jul 29, 3:19 PM MST	Special Weather Statement	PSR	Yuma	41 min
Jul 29, 3:23 PM MST	Special Weather Statement	PSR	Gila	52 min
Jul 29, 3:53 PM MST	Areal Flood Advisory	PSR	La Paz, Maricopa, Yuma	3 hr
Jul 29, 3:59 PM MST	Special Weather Statement	PSR		61 min
Jul 29, 4:00 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Jul 29, 4:17 PM MST	Special Weather Statement	PSR	La Paz	58 min
Jul 29, 4:18 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Jul 29, 4:40 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Jul 29, 4:42 PM MST	Areal Flood Advisory	PSR	Yuma	3 hr
Jul 29, 4:48 PM MST	Special Weather Statement	PSR		57 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.