Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 126, NWS Phoenix, AZ

August 1, 2021Gila County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Aug 1, 2021, 7:26 PM MST for Gila County, Arizona. It was in force for 2 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: Aug 1, 2021, 7:26 PM MST (02:26 UTC)
Expired: Aug 1, 2021, 9:53 PM MST
In force: 2 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Gila County, AZ

The radar

The Flagstaff radar (KFSX), 104 km from the middle of the area, began a volume at 02:25 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
Aug 1, 9:50 PM MST	FLASH FLOOD	22 Nw Hilltop, AZ	* DELAYED REPORT * USGS STREAMGAUGE #09497800 CIBECUE CREEK NEAR CHRYSOTILE MEASURED AN APPROXIMATE 4 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 00:00Z, 2.4 hours before the alert went out and 132 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: 748 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 2842 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 6 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

626 
WGUS55 KPSR 020226
FFWPSR
AZC007-020615-
/O.NEW.KPSR.FF.W.0126.210802T0226Z-210802T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
726 PM MST Sun Aug 1 2021

The National Weather Service in Phoenix has issued a

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

* Until 1115 PM MST.

* At 726 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over tributaries to the Salt River. Concerning 
  tributaries are Cibicue Creek and Canyon Creek. Between 0.5 and 
  1.5 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.

  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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3383 11052 3381 11050 3378 11052 3380 11063
      3366 11075 3367 11076 3380 11067 3385 11056

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

$$

SDB

1 follow-up statement

329 
WGUS75 KPSR 020453
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
953 PM MST Sun Aug 1 2021

AZC007-020503-
/O.CAN.KPSR.FF.W.0126.000000T0000Z-210802T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
953 PM MST Sun Aug 1 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, however there still may be 
swift water in the tributaries of the Salt River. Please continue to 
use caution in these areas and heed any road closures.

LAT...LON 3383 11052 3381 11050 3378 11052 3380 11063
      3366 11075 3367 11076 3380 11067 3385 11056

$$

Hirsch

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 1, 5:25 PM MST	Special Weather Statement	PSR		35 min
Aug 1, 5:47 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Aug 2, 6:46 AM MST	Areal Flood Warning	PSR	Gila	12 hr
Aug 2, 1:45 PM MST	Excessive Heat Warning	PSR	La Paz, Maricopa, Pinal, Yuma	3 days

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.