Alert archive / Arizona / Flash Flood Warnings in 2018

Flash Flood Warning 13, NWS Phoenix, AZ

July 11, 2018La Paz County, Yuma County, Arizona; Imperial County, Riverside County, California

NWS Phoenix, AZ issued this flash flood warning at Jul 11, 2018, 1:05 PM MST for La Paz County, Yuma County, Arizona; Imperial County, Riverside 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 11, 2018, 1:05 PM MST (20:05 UTC)
Expired: Jul 11, 2018, 5:00 PM MST
In force: 4 hr
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Flood severity: None

Counties La Paz County, AZ, Yuma County, AZ, Imperial County, CA, Riverside County, CA

The radar

The Yuma radar (KYUX), 140 km from the middle of the area, began a volume at 20:08 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

Time	Report	Where	Remark
Jul 11, 2:30 PM MST	FLASH FLOOD	1 Nw Quartzsite, AZ	SEVERAL ROADS FLOODED AND CLOSED IN QUARTZSITE INCLUDING MOON MOUNTAIN AVE AND QUAIL TRAIL.

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

The nearest sounding before it

Yuma Prvg Ground, AZ (K1Y7), launched 12:00Z, 8.1 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: 677 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 1547 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -9 m²/s²
0-3 km storm-relative helicity: 1 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

279 
WGUS55 KPSR 112005
FFWPSR
AZC012-027-CAC025-065-120000-
/O.NEW.KPSR.FF.W.0013.180711T2005Z-180712T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
105 PM MST WED JUL 11 2018

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  Central La Paz County in west central Arizona...
  North central Yuma County in southwestern Arizona...
  Northeastern Imperial County in southeastern California...
  Riverside County in southern California...

* Until 500 PM MST/500 PM PDT/.

* At 105 PM MST/105 PM PDT/, Doppler radar and automated rain gauges
  indicated thunderstorms producing heavy rain across the warned
  area. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Blythe, Quartzsite, Cibola, Salome, Brenda, Bouse, Vicksburg
  Junction, Wenden, Kofa Wildlife Refuge, Vicksburg, Harcuvar, Palm
  Canyon and Ehrenberg.

* This includes the following highways...
  AZ Interstate 10 between mile markers 1 and 51.
  US Highway 60 between mile markers 31 and 61.
  AZ Route 72 between mile markers 14 and 49.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3401 11406 3384 11353 3323 11389 3326 11429
      3331 11476 3401 11423

$$

WATERS

2 follow-up statements

984 
WGUS75 KPSR 112131
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
231 PM MST WED JUL 11 2018

AZC012-027-CAC025-065-120000-
/O.CON.KPSR.FF.W.0013.000000T0000Z-180712T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-Yuma AZ-Imperial CA-Riverside CA-
231 PM MST WED JUL 11 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 500 PM MST/500 PM
PDT/ FOR CENTRAL LA PAZ...NORTH CENTRAL YUMA...NORTHEASTERN IMPERIAL
AND RIVERSIDE COUNTIES...

At 229 PM MST/229 PM PDT/, Doppler radar and automated rain gauges 
indicated heavy rain has fallen over the warned area. Up to two 
inches of rain have already fallen. Flash flooding is expected to 
begin shortly.

Some locations that will experience flooding include...
Blythe, Quartzsite, Cibola, Salome, Brenda, Bouse, Vicksburg
Junction, Wenden, Kofa Wildlife Refuge, Vicksburg, Harcuvar, Palm
Canyon and Ehrenberg.

This includes the following highways...
AZ Interstate 10 between mile markers 1 and 51.
US Highway 60 between mile markers 31 and 61.
AZ Route 72 between mile markers 14 and 49.

Additional rainfall amounts of up to one inch are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3401 11406 3384 11353 3323 11389 3326 11429
      3331 11476 3401 11423

$$

CK

208 
WGUS75 KPSR 112351
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
451 PM MST WED JUL 11 2018

AZC012-027-CAC025-065-120000-
/O.EXP.KPSR.FF.W.0013.000000T0000Z-180712T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-Yuma AZ-Imperial CA-Riverside CA-
451 PM MST WED JUL 11 2018

...THE FLASH FLOOD WARNING FOR CENTRAL LA PAZ...NORTH CENTRAL YUMA...
NORTHEASTERN IMPERIAL AND RIVERSIDE COUNTIES WILL EXPIRE AT 500 PM
MST/500 PM PDT/...

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

LAT...LON 3401 11406 3384 11353 3323 11389 3326 11429
      3331 11476 3401 11423

$$

CK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 5:17 PM MST	Special Weather Statement	PSR	Maricopa	28 min
Jul 10, 5:18 PM MST	Areal Flood Advisory	PSR	Maricopa	88 min
Jul 10, 5:20 PM MST	Special Weather Statement	PSR	Maricopa	40 min
Jul 10, 6:08 PM MST	Special Weather Statement	PSR		37 min
Jul 11, 5:54 AM MST	Areal Flood Advisory	PSR	La Paz	2 hr
Jul 11, 11:34 AM MST	Special Weather Statement	PSR	Gila	41 min
Jul 11, 11:38 AM MST	Special Weather Statement	PSR	La Paz	52 min
Jul 11, 11:41 AM MST	Flash Flood Watch	PSR	Gila, La Paz, Maricopa, Pinal, Yuma	14 hr
Jul 11, 12:00 PM MST	Flash Flood Warning	PSR	Gila	3 hr
Jul 11, 12:16 PM MST	Special Weather Statement	PSR	Gila	44 min
Jul 11, 12:23 PM MST	Special Weather Statement	PSR	La Paz	52 min
Jul 11, 12:28 PM MST	Special Weather Statement	PSR	La Paz	47 min
Jul 11, 1:09 PM MST	Special Weather Statement	PSR	La Paz	51 min
Jul 11, 1:13 PM MST	Special Weather Statement	PSR		47 min
Jul 11, 1:28 PM MST	Special Weather Statement	PSR	Pinal	47 min
Jul 11, 1:49 PM MST	Special Weather Statement	PSR		41 min
Jul 11, 1:54 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	51 min
Jul 11, 2:02 PM MST	Areal Flood Advisory	PSR	La Paz, Yuma	3 hr
Jul 11, 2:11 PM MST	Special Weather Statement	PSR	Pinal	49 min
Jul 11, 2:20 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Jul 11, 2:40 PM MST	Special Weather Statement	PSR	Pinal	50 min
Jul 11, 2:42 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	48 min
Jul 11, 2:58 PM MST	Areal Flood Advisory	PSR	La Paz, Maricopa	3 hr
Jul 11, 3:09 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	51 min
Jul 11, 3:31 PM MST	Areal Flood Advisory	PSR	Maricopa, Pinal	119 min
Jul 11, 3:54 PM MST	Special Weather Statement	PSR		51 min
Jul 11, 3:56 PM MST	Special Weather Statement	PSR	Maricopa	49 min
Jul 11, 4:03 PM MST	Flash Flood Warning	PSR	Maricopa, Pinal	3 hr
Jul 11, 4:12 PM MST	Special Weather Statement	PSR	Gila	48 min
Jul 11, 4:14 PM MST	Special Weather Statement	PSR		46 min
Jul 11, 4:25 PM MST	Special Weather Statement	PSR	Maricopa	50 min
Jul 11, 4:26 PM MST	Areal Flood Advisory	PSR	Maricopa	2 hr
Jul 11, 4:57 PM MST	Special Weather Statement	PSR	Maricopa	48 min
Jul 11, 4:59 PM MST	Dust Storm Advisory	PSR	Maricopa, Pinal	46 min
Jul 11, 2:36 PM MST	Areal Flood Advisory	PSR	Riverside, San Bernardino	3 hr
Jul 11, 3:23 PM MST	Dust Storm Advisory	PSR	Imperial, Riverside	52 min
Jul 11, 3:42 PM MST	Flash Flood Warning	PSR	Riverside	4 hr
Jul 11, 4:08 PM MST	Areal Flood Advisory	PSR	Riverside, San Bernardino	3 hr
Jul 11, 4:30 PM MST	Special Weather Statement	PSR	Riverside	45 min
Jul 11, 4:49 PM MST	Flash Flood Warning	PSR	Riverside, San Bernardino	3 hr

Nearby

Flash Flood Warnings in Arizona, 2018 Flash Flood Warnings in California, 2018 Every flash flood warning in 2018

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.