Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 164, NWS Phoenix, AZ

August 12, 2021La Paz County, Yuma County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Aug 12, 2021, 8:48 PM MST for La Paz County, Yuma 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
Aug 12, 2021, 8:48 PM MST (03:48 UTC)
Expired
Aug 13, 2021, 12:45 AM MST
In force
4 hr
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

Counties La Paz County, AZ, Yuma County, AZ

The radar

The Yuma radar (KYUX), 149 km from the middle of the area, began a volume at 03:49 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, 3.8 hours before the alert went out and 197 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-pSkew-T log-p diagram, Phoenix, AZ at 00:00Z on 2021-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 760 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2021-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
760 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1919 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

680 
WGUS55 KPSR 130348
FFWPSR
AZC012-027-130745-
/O.NEW.KPSR.FF.W.0164.210813T0348Z-210813T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
848 PM MST Thu Aug 12 2021

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  North Central Yuma County in southwestern Arizona...
  Central La Paz County in west central Arizona...

* Until 1245 AM MST.

* At 848 PM MST, La Paz County Sheriffs Office reported Highway 72 
  had flooding causing the road to be impassable. Between 1 and 1.5 
  inches of rain fell earlier. Flash flooding is also expected to 
  affect other areas including Highway 95.

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

  SOURCE...Law enforcement reported.

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

* Some locations that will experience flash flooding include...
  Quartzsite, Brenda, Kofa Wildlife Refuge, Bouse, Vicksburg 
  Junction and Vicksburg.

This includes the following highways...
	AZ Interstate 10 between mile markers 17 and 26.
	AZ Route 72 between mile markers 16 and 25.
	AZ Route 95 between mile markers 100 and 112.
	US Highway 60 between mile markers 31 and 40.

This includes the following streams and drainages...
  Bouse Wash, Cunningham Wash, Tyson Wash, Alamo Wash, Apache Wash, 
  Red Raven Wash, Plomosa Wash, Poormans Wash, and Cholla Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3339 11429 3379 11424 3380 11397 3397 11418
      3402 11416 3402 11402 3372 11368 3355 11373

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

AJ
2 follow-up statements
361 
WGUS75 KPSR 130511 RRA
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1011 PM MST Thu Aug 12 2021

AZC012-027-130745-
/O.CON.KPSR.FF.W.0164.000000T0000Z-210813T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-Yuma AZ-
1011 PM MST Thu Aug 12 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM MST FRIDAY 
FOR NORTH CENTRAL YUMA AND CENTRAL LA PAZ COUNTIES...

At 1011 PM MST, local law enforcement reported thunderstorms 
produced heavy rain across the warned area. Between 1 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...Law enforcement reported.

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

Some locations that will experience flash flooding include...
  Quartzsite, Brenda, Kofa Wildlife Refuge, Bouse, Vicksburg 
  Junction and Vicksburg.

This includes the following highways...
	AZ Interstate 10 between mile markers 17 and 26.
	AZ Route 72 between mile markers 16 and 25.
	AZ Route 95 between mile markers 100 and 103...and
	between mile markers 104 and 112.
	US Highway 60 between mile markers 31 and 40.

This includes the following streams and drainages...
  Alamo Wash, Apache Wash, Red Raven Wash, Calcite Wash, Cave Creek, 
  Scaddan Wash, Plomosa Wash, Cunningham Wash, Tyson Wash, French 
  Creek, Bouse Wash, Poormans Wash, Cholla Wash, La and Smith Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3339 11429 3379 11424 3380 11397 3397 11418
      3402 11416 3402 11402 3372 11368 3355 11373

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Rogers
033 
WGUS75 KPSR 130742
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1242 AM MST Fri Aug 13 2021

AZC012-027-130752-
/O.EXP.KPSR.FF.W.0164.000000T0000Z-210813T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-Yuma AZ-
1242 AM MST Fri Aug 13 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1245 AM MST EARLY THIS MORNING 
FOR NORTH CENTRAL YUMA AND CENTRAL LA PAZ COUNTIES...

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

LAT...LON 3339 11429 3379 11424 3380 11397 3397 11418
      3402 11416 3402 11402 3372 11368 3355 11373

$$

CK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 5:16 PM MSTSpecial Weather StatementPSRYuma44 min
Aug 12, 5:17 PM MSTSpecial Weather StatementPSRYuma43 min
Aug 12, 5:53 PM MSTAreal Flood AdvisoryPSRYuma3 hr
Aug 12, 6:28 PM MSTSpecial Weather StatementPSRLa Paz47 min
Aug 12, 6:30 PM MSTSpecial Weather StatementPSRYuma45 min
Aug 12, 6:42 PM MSTAreal Flood AdvisoryPSRLa Paz3 hr
Aug 12, 6:47 PM MSTAreal Flood AdvisoryPSRMaricopa, Yuma3 hr
Aug 12, 6:50 PM MSTSevere Thunderstorm WarningPSRYuma40 min
Aug 12, 6:52 PM MSTSevere Thunderstorm WarningPSRLa Paz38 min
Aug 12, 7:16 PM MSTFlash Flood Warning Considerable damage threatPSRYuma4 hr
Aug 12, 7:25 PM MSTSevere Thunderstorm WarningPSRLa Paz50 min
Aug 12, 7:42 PM MSTAreal Flood AdvisoryPSRLa Paz, Yuma3 hr
Aug 12, 7:56 PM MSTSpecial Weather StatementPSRLa Paz49 min
Aug 12, 8:05 PM MSTDust Storm AdvisoryPSRLa Paz, Yuma55 min
Aug 13, 2:50 PM MSTSpecial Weather StatementPSRGila40 min
Aug 13, 3:30 PM MSTSevere Thunderstorm WarningPSRGila45 min
Aug 13, 3:36 PM MSTFlash Flood Warning Considerable damage threatPSRGila4 hr
Aug 13, 4:12 PM MSTFlash Flood Warning Considerable damage threatPSRGila4 hr
Aug 13, 4:14 PM MSTSpecial Weather StatementPSRGila46 min
Aug 13, 4:34 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa, Pinal41 min

Nearby

Flash Flood Warnings in Arizona, 2021Every 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.