Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 52, NWS Phoenix, AZ

July 21, 2021La Paz County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 21, 2021, 4:55 PM MST for La Paz 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 21, 2021, 4:55 PM MST (23:55 UTC)
Expired
Jul 21, 2021, 9:00 PM MST
In force
4 hr
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County La Paz County, AZ

The radar

The Yuma radar (KYUX), 168 km from the middle of the area, began a volume at 23:56 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 12:00Z, 11.9 hours before the alert went out and 167 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 12:00Z on 2021-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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 12:00Z on 2021-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -11 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
5 J/kg
Mixed-layer CIN
-244 J/kg
Mixed-layer LCL
2438 m above ground
0-6 km bulk shear
2 kt
0-1 km storm-relative helicity
-11 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

096 
WGUS55 KPSR 212355
FFWPSR
AZC012-220400-
/O.NEW.KPSR.FF.W.0052.210721T2355Z-210722T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
455 PM MST Wed Jul 21 2021

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  East Central La Paz County in west central Arizona...

* Until 900 PM MST.

* At 455 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. 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...
  Vicksburg, Vicksburg Junction, Harcuvar, Salome, Brenda and Wenden.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3383 11356 3372 11350 3360 11378 3370 11404
      3390 11396 3394 11362

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

$$

MS
2 follow-up statements
207 
WGUS75 KPSR 220116
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
616 PM MST Wed Jul 21 2021

AZC012-220400-
/O.CON.KPSR.FF.W.0052.000000T0000Z-210722T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-
616 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 PM MST THIS EVENING 
FOR EAST CENTRAL LA PAZ COUNTY...

At 616 PM MST, Doppler radar indicated heavy rain had fallen across 
the warned area. Between 0.5 and 1.5 inches of rain had fallen. 
Flash flooding is likely along low water crossings and area washes.

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...
  Vicksburg, Vicksburg Junction, Harcuvar, Salome, Brenda and Wenden.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3383 11356 3372 11350 3360 11378 3370 11404
      3390 11396 3394 11362

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

$$

MS
601 
WGUS75 KPSR 220402
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
902 PM MST Wed Jul 21 2021

AZC012-220412-
/O.EXP.KPSR.FF.W.0052.000000T0000Z-210722T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-
902 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR EAST CENTRAL LA PAZ COUNTY...

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

LAT...LON 3383 11356 3372 11350 3360 11378 3370 11404
      3390 11396 3394 11362

$$

Iniguez

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 5:15 PM MSTSpecial Weather StatementPSRLa Paz45 min
Jul 20, 5:21 PM MSTSpecial Weather StatementPSRGila39 min
Jul 20, 5:32 PM MSTAreal Flood AdvisoryPSRMaricopa3 hr
Jul 20, 6:22 PM MSTSpecial Weather StatementPSR38 min
Jul 20, 7:22 PM MSTSpecial Weather StatementPSRPinal53 min
Jul 20, 8:19 PM MSTSpecial Weather StatementPSRPinal41 min
Jul 20, 8:56 PM MSTSpecial Weather StatementPSRPinal49 min
Jul 20, 11:51 PM MSTSpecial Weather StatementPSR39 min
Jul 21, 2:21 AM MSTFlash Flood WatchPSRGila, Maricopa, Pinal5 days
Jul 21, 8:12 AM MSTBlowing Dust AdvisoryPSRLa Paz, Maricopa, Yuma12 hr
Jul 21, 2:45 PM MSTSpecial Weather StatementPSR45 min
Jul 21, 2:46 PM MSTDust Storm WarningPSRPinal40 min
Jul 21, 3:07 PM MSTSpecial Weather StatementPSR38 min
Jul 21, 3:34 PM MSTSpecial Weather StatementPSRMaricopa41 min
Jul 21, 3:37 PM MSTSpecial Weather StatementPSRLa Paz38 min
Jul 21, 3:42 PM MSTSpecial Weather StatementPSRYuma48 min
Jul 21, 3:45 PM MSTSpecial Weather StatementPSRMaricopa45 min
Jul 21, 3:46 PM MSTSpecial Weather StatementPSR29 min
Jul 21, 3:51 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Jul 21, 3:53 PM MSTSevere Thunderstorm WarningPSRMaricopa37 min
Jul 21, 3:55 PM MSTSpecial Weather StatementPSRMaricopa50 min
Jul 21, 4:01 PM MSTSevere Thunderstorm WarningPSRMaricopa29 min
Jul 21, 4:11 PM MSTSpecial Weather StatementPSRLa Paz49 min
Jul 21, 4:26 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa4 hr
Jul 21, 4:28 PM MSTSpecial Weather StatementPSRMaricopa47 min
Jul 21, 4:32 PM MSTSpecial Weather StatementPSR28 min
Jul 21, 4:59 PM MSTSpecial Weather StatementPSR46 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.