Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 121, NWS Phoenix, AZ

July 30, 2021Yuma County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 30, 2021, 7:25 PM MST for Yuma County, Arizona. It was in force for 3 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 30, 2021, 7:25 PM MST (02:25 UTC)
Expired: Jul 30, 2021, 10:18 PM MST
In force: 3 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Yuma County, AZ

The radar

The Yuma radar (KYUX), 30 km from the middle of the area, began a volume at 02:28 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, 2.4 hours before the alert went out and 244 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: 50 J/kg
Mixed-layer CIN: -40 J/kg
Mixed-layer LCL: 3059 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: 1 m²/s²
0-3 km storm-relative helicity: 43 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

077 
WGUS55 KPSR 310225
FFWPSR
AZC027-310630-
/O.NEW.KPSR.FF.W.0121.210731T0225Z-210731T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
725 PM MST Fri Jul 30 2021

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  West Central Yuma County in southwestern Arizona...

* Until 1130 PM MST.

* At 725 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 0.5 and 1 inch of rain 
  has fallen. Additional rainfall amounts up to 0.5 inches are 
  possible in the warned area. 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...
  Yuma, Fortuna Foothills, Blaisdell, Ligurta, Kinter and Araby.

This includes the following highways...
	AZ Route 95 between mile markers 29 and 38.
	AZ Interstate 8 between mile markers 10 and 19.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3276 11454 3278 11433 3258 11425 3252 11438
      3268 11453

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

$$

INS

2 follow-up statements

182 
WGUS75 KPSR 310327
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
827 PM MST Fri Jul 30 2021

AZC027-310630-
/O.CON.KPSR.FF.W.0121.000000T0000Z-210731T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yuma AZ-
827 PM MST Fri Jul 30 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1130 PM MST THIS 
EVENING FOR WEST CENTRAL YUMA COUNTY...

At 827 PM MST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 0.5 and 1 inch of rain has 
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...
  Yuma, Fortuna Foothills, Blaisdell, Ligurta, Kinter and Araby.

This includes the following highways...
	AZ Route 95 between mile markers 29 and 38.
	AZ Interstate 8 between mile markers 10 and 19.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3276 11454 3278 11433 3258 11425 3252 11438
      3268 11453

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

$$

INS

623 
WGUS75 KPSR 310518
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1018 PM MST Fri Jul 30 2021

AZC027-310528-
/O.CAN.KPSR.FF.W.0121.000000T0000Z-210731T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yuma AZ-
1018 PM MST Fri Jul 30 2021

...FLASH FLOOD WARNING IS CANCELLED FOR WEST CENTRAL YUMA COUNTY...

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.

A Flash Flood Watch remains in effect until 500 AM MST Saturday for 
portions of Arizona and California.

LAT...LON 3276 11454 3278 11433 3258 11425 3252 11438
      3268 11453

$$

Hirsch

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 30, 5:04 PM MST	Dust Storm Advisory	PSR	Yuma	41 min
Jul 30, 5:29 PM MST	Severe Thunderstorm Warning	PSR	Yuma	46 min
Jul 30, 5:39 PM MST	Areal Flood Advisory	PSR	Yuma	3 hr
Jul 30, 5:44 PM MST	Flash Flood Warning Considerable damage threat	PSR	Yuma	4 hr
Jul 30, 5:59 PM MST	Dust Storm Warning	PSR	Yuma	45 min
Jul 30, 6:06 PM MST	Flash Flood Warning Considerable damage threat	PSR	Yuma	4 hr
Jul 30, 6:51 PM MST	Severe Thunderstorm Warning	PSR	Yuma	38 min
Jul 30, 7:06 PM MST	Special Weather Statement	PSR	Pinal	24 min
Jul 30, 7:32 PM MST	Areal Flood Advisory	PSR	Yuma	3 hr
Jul 30, 7:51 PM MST	Special Weather Statement	PSR	Yuma	69 min
Jul 30, 8:02 PM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Jul 30, 8:29 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	72 min
Jul 30, 8:44 PM MST	Severe Thunderstorm Warning	PSR	La Paz, Maricopa	61 min
Jul 30, 9:17 PM MST	Flash Flood Warning Considerable damage threat	PSR	Maricopa	2 hr
Jul 30, 9:40 PM MST	Special Weather Statement	PSR	Maricopa	65 min
Jul 30, 10:24 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	43 min
Jul 30, 10:37 PM MST	Special Weather Statement	PSR	Maricopa	23 min
Jul 30, 10:45 PM MST	Special Weather Statement	PSR		45 min
Jul 30, 11:54 PM MST	Special Weather Statement	PSR	Maricopa	51 min
Jul 31, 12:37 AM MST	Areal Flood Advisory	PSR	Maricopa	3 hr
Jul 31, 1:34 AM MST	Areal Flood Advisory	PSR	Maricopa	4 hr
Jul 31, 1:58 AM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	4 hr
Jul 31, 3:39 AM MST	Areal Flood Advisory	PSR	La Paz	4 hr
Jul 31, 2:23 PM MST	Special Weather Statement	PSR	La Paz	37 min
Jul 31, 3:03 PM MST	Special Weather Statement	PSR	Gila	27 min
Jul 31, 3:18 PM MST	Special Weather Statement	PSR	La Paz	27 min
Jul 31, 3:31 PM MST	Flash Flood Warning Considerable damage threat	PSR	Gila	4 hr
Jul 31, 3:44 PM MST	Special Weather Statement	PSR	La Paz	31 min
Jul 31, 3:55 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.