Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 111, NWS Phoenix, AZ

July 29, 2021Gila County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 29, 2021, 8:02 PM MST for Gila County, Arizona. It was in force for 6 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, 8:02 PM MST (03:02 UTC)
Expired: Jul 30, 2021, 2:00 AM MST
In force: 6 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), 70 km from the middle of the area, began a volume at 03:02 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, 8:20 PM MST	FLASH FLOOD	2 Ne Punkin Center, AZ	* DELAYED REPORT * USGS STREAMGAUGE #09499000 TONTO CREEK ABOVE GUN CREEK REACHED AND EXCEEDED ACTION STAGE WITH FLOOD WATERS IMPACTING CROSSINGS OF TONTO CREEK DOWNSTREAM OF GAUGE. PUBLIC CONFIRMED ROAD CLOSURE DUE TO FLOODING. TIME ESTIMATED FROM GAUGE R

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 00:00Z, 3.0 hours before the alert went out and 77 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: 237 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 3197 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

787 
WGUS55 KPSR 300302
FFWPSR
AZC007-300900-
/O.NEW.KPSR.FF.W.0111.210730T0302Z-210730T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
802 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 200 AM MST.

* At 802 PM MST, gauge reports indicated thunderstorms producing 
  heavy rain across the warned area. Flash flooding is ongoing or 
  expected to begin shortly.

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

  SOURCE...Gauges reported.

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

* Some locations that will experience flash flooding include...
  Tonto Basin and Punkin Center.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3392 11130 3389 11130 3382 11128 3379 11125
      3376 11123 3374 11126 3376 11128 3380 11131
      3384 11133 3389 11133 3393 11133

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

$$

JS

3 follow-up statements

652 
WGUS75 KPSR 300320
FFSPSR

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

AZC007-300900-
/O.CON.KPSR.FF.W.0111.000000T0000Z-210730T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
820 PM MST Thu Jul 29 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 AM MST FRIDAY FOR 
GILA COUNTY...

At 820 PM MST, Gauge reports along Tonto Creek indicate high flow 
levels making unbridged crossings impassable. Flooding is expected 
to continue for at least the next few hours.

HAZARD...Life threatening flash flooding. Heavy rainfall
         upstream.

SOURCE...Gauges reported.

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

Some locations that will experience flash flooding include...
  Tonto Basin and Punkin Center.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3392 11130 3389 11130 3382 11128 3379 11125
      3376 11123 3374 11126 3376 11128 3380 11131
      3384 11133 3389 11133 3393 11133

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

$$

Hirsch

172 
WGUS75 KPSR 300738
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1238 AM MST Fri Jul 30 2021

AZC007-300900-
/O.CON.KPSR.FF.W.0111.000000T0000Z-210730T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
1238 AM MST Fri Jul 30 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 AM MST EARLY THIS 
MORNING FOR GILA COUNTY...

At 1238 AM MST, gauge reports indicated thunderstorms producing 
heavy rain across the warned area. Flash flooding is ongoing or 
expected to begin shortly.

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

SOURCE...Gauges reported.

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

Some locations that will experience flash flooding include...
  Tonto Basin and Punkin Center.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3392 11130 3389 11130 3382 11128 3379 11125
      3376 11123 3374 11126 3376 11128 3380 11131
      3384 11133 3389 11133 3393 11133

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

$$

Rogers

862 
WGUS75 KPSR 300902
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
202 AM MST Fri Jul 30 2021

AZC007-300912-
/O.EXP.KPSR.FF.W.0111.000000T0000Z-210730T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
202 AM MST Fri Jul 30 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR GILA COUNTY...

Flood waters continue to recede in Tonto Creek according to gauge 
data. Flooding is no longer expected to pose a threat. Please 
continue to heed remaining road closures.

LAT...LON 3392 11130 3389 11130 3382 11128 3379 11125
      3376 11123 3374 11126 3376 11128 3380 11131
      3384 11133 3389 11133 3393 11133

$$

Rogers

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 6:17 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	3 hr
Jul 30, 7:28 AM MST	Areal Flood Warning	PSR	Gila	13 hr
Jul 30, 12:36 PM MST	Special Weather Statement	PSR	La Paz	24 min
Jul 30, 1:03 PM MST	Special Weather Statement	PSR		27 min
Jul 30, 1:19 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Jul 30, 2:24 PM MST	Special Weather Statement	PSR		36 min
Jul 30, 2:59 PM MST	Special Weather Statement	PSR		31 min
Jul 30, 4:43 PM MST	Special Weather Statement	PSR		32 min
Jul 30, 4:50 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	69 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.