Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 119, NWS Phoenix, AZ

July 30, 2021Yuma County, Arizona; Imperial County, California

NWS Phoenix, AZ issued this flash flood warning at Jul 30, 2021, 6:06 PM MST for Yuma County, Arizona; Imperial County, California. It was in force for 4 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 30, 2021, 6:06 PM MST (01:06 UTC)
Expired
Jul 30, 2021, 10:15 PM MST
In force
4 hr
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

Counties Yuma County, AZ, Imperial County, CA

The radar

The Yuma radar (KYUX), 25 km from the middle of the area, began a volume at 01:08 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

TimeReportWhereRemark
Jul 30, 7:53 PM MSTFLASH FLOOD3 E Felicity, CA***DELAYED REPORT*** ARAZ ROAD CLOSED DUE TO FLOODING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

San Diego, CA (KNKX), launched 00:00Z, 1.1 hours before the alert went out and 236 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, San Diego, CA at 00:00Z on 2021-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, San Diego, CA at 00:00Z on 2021-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2564 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

682 
WGUS55 KPSR 310106
FFWPSR
AZC027-CAC025-310515-
/O.NEW.KPSR.FF.W.0119.210731T0106Z-210731T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  Western Yuma County in southwestern Arizona...
  Southeastern Imperial County in southeastern California...

* Until 1015 PM MST /1015 PM PDT/.

* At 606 PM MST /606 PM PDT/, Doppler radar indicated thunderstorms 
  producing heavy rain across the warned area. Between 1 and 1.5 
  inches of rain have fallen. Additional rainfall amounts of 0.5 to 
  1 inch 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, Winterhaven and Andrade.

This includes the following highways...
	CA Interstate 8 between mile markers 89 and 96.
	AZ Interstate 8 between mile markers 1 and 6.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3271 11478 3283 11471 3287 11463 3281 11454
      3268 11453 3262 11457 3268 11466 3267 11475
      3268 11474 3270 11473 3271 11473 3272 11472

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

$$

INS
2 follow-up statements
426 
WGUS75 KPSR 310215
FFSPSR

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

AZC027-CAC025-310515-
/O.CON.KPSR.FF.W.0119.000000T0000Z-210731T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yuma AZ-Imperial CA-
715 PM MST Fri Jul 30 2021 /715 PM PDT Fri Jul 30 2021/

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1015 PM MST/1015 PM 
PDT/ THIS EVENING FOR WESTERN YUMA AND SOUTHEASTERN IMPERIAL 
COUNTIES...

At 715 PM MST /715 PM PDT/, Doppler radar indicated thunderstorms 
producing heavy rain across the warned area. Between 1 and 2 inches 
of rain have 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, Winterhaven and Andrade.

This includes the following highways...
	CA Interstate 8 between mile markers 89 and 96.
	AZ Interstate 8 between mile markers 1 and 6.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3271 11478 3283 11471 3287 11463 3281 11454
      3268 11453 3262 11457 3268 11466 3267 11475
      3268 11474 3270 11473 3271 11473 3272 11472

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

$$

INS
254 
WGUS75 KPSR 310519
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1019 PM PDT Fri Jul 30 2021

CAC025-310529-
/O.EXP.KPSR.FF.W.0119.000000T0000Z-210731T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Imperial CA-
1019 PM PDT Fri Jul 30 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR WESTERN YUMA AND SOUTHEASTERN 
IMPERIAL 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.

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

LAT...LON 3271 11478 3283 11471 3287 11463 3281 11454
      3268 11453 3262 11457 3268 11466 3267 11475
      3268 11474 3270 11473 3271 11473 3272 11472

$$

Hirsch

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 5:04 PM MSTDust Storm AdvisoryPSRYuma41 min
Jul 30, 5:29 PM MSTSevere Thunderstorm WarningPSRYuma46 min
Jul 30, 5:39 PM MSTAreal Flood AdvisoryPSRYuma3 hr
Jul 30, 5:44 PM MSTFlash Flood Warning Considerable damage threatPSRYuma4 hr
Jul 30, 5:59 PM MSTDust Storm WarningPSRYuma45 min
Jul 30, 6:51 PM MSTSevere Thunderstorm WarningPSRYuma38 min
Jul 30, 7:06 PM MSTSpecial Weather StatementPSRPinal24 min
Jul 30, 7:25 PM MSTFlash Flood Warning Considerable damage threatPSRYuma3 hr
Jul 30, 7:32 PM MSTAreal Flood AdvisoryPSRYuma3 hr
Jul 30, 7:51 PM MSTSpecial Weather StatementPSRYuma69 min
Jul 30, 8:02 PM MSTAreal Flood AdvisoryPSRMaricopa3 hr
Jul 30, 8:29 PM MSTDust Storm AdvisoryPSRMaricopa, Pinal72 min
Jul 30, 8:44 PM MSTSevere Thunderstorm WarningPSRLa Paz, Maricopa61 min
Jul 30, 9:17 PM MSTFlash Flood Warning Considerable damage threatPSRMaricopa2 hr
Jul 30, 9:40 PM MSTSpecial Weather StatementPSRMaricopa65 min
Jul 30, 10:24 PM MSTDust Storm AdvisoryPSRMaricopa, Pinal43 min
Jul 30, 10:37 PM MSTSpecial Weather StatementPSRMaricopa23 min
Jul 30, 10:45 PM MSTSpecial Weather StatementPSR45 min
Jul 30, 11:54 PM MSTSpecial Weather StatementPSRMaricopa51 min
Jul 31, 12:37 AM MSTAreal Flood AdvisoryPSRMaricopa3 hr
Jul 31, 1:34 AM MSTAreal Flood AdvisoryPSRMaricopa4 hr
Jul 31, 1:58 AM MSTAreal Flood AdvisoryPSRMaricopa, Pinal4 hr
Jul 31, 3:39 AM MSTAreal Flood AdvisoryPSRLa Paz4 hr
Jul 31, 2:23 PM MSTSpecial Weather StatementPSRLa Paz37 min
Jul 31, 3:03 PM MSTSpecial Weather StatementPSRGila27 min
Jul 31, 3:18 PM MSTSpecial Weather StatementPSRLa Paz27 min
Jul 31, 3:31 PM MSTFlash Flood Warning Considerable damage threatPSRGila4 hr
Jul 31, 3:44 PM MSTSpecial Weather StatementPSRLa Paz31 min
Jul 31, 3:55 PM MSTAreal Flood AdvisoryPSRLa Paz3 hr
Jul 30, 5:18 PM MSTSpecial Weather StatementPSRImperial72 min
Jul 30, 5:20 PM MSTSpecial Weather StatementPSRRiverside70 min
Jul 30, 5:24 PM MSTFlash Flood Warning Considerable damage threatPSRRiverside4 hr
Jul 30, 5:33 PM MSTFlash Flood Warning Considerable damage threatPSRImperial4 hr
Jul 30, 5:52 PM MSTFlash Flood Warning Considerable damage threatPSRRiverside4 hr
Jul 30, 6:11 PM MSTSevere Thunderstorm WarningPSRRiverside79 min
Jul 30, 6:31 PM MSTSpecial Weather StatementPSRImperial74 min
Jul 30, 6:49 PM MSTFlash Flood Warning Considerable damage threatPSRImperial, Riverside4 hr
Jul 31, 2:32 PM MSTSpecial Weather StatementPSRRiverside28 min
Jul 31, 3:47 PM MSTSpecial Weather StatementPSRRiverside28 min
Jul 31, 4:48 PM MSTFlash Flood Warning Considerable damage threatPSRRiverside3 hr

Nearby

Flash Flood Warnings in Arizona, 2021Flash Flood Warnings in California, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.