Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 134, NWS Las Vegas, NV

August 20, 2012Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood warning at Aug 20, 2012, 4:14 PM MST for Mohave County, Arizona. It was in force for 2 hr. 2 reports 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
Aug 20, 2012, 4:14 PM MST (23:14 UTC)
Expired
Aug 20, 2012, 6:15 PM MST
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County Mohave County, AZ

The radar

The Las Vegas radar (KESX), 160 km from the middle of the area, began a volume at 23:16 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
Aug 20, 4:32 PM MSTHEAVY RAIN 1.1Wikieup, AZA MOHAVE COUNTY ALERT GAUGE REPORTED 1.10 INCHES OF RAIN FELL BETWEEN 400 PM AND 430 PM.
Aug 20, 5:18 PM MSTFLASH FLOODNe Wikieup, AZMOHAVE COUNTY SHERIFF REPORTED LOTS OF MUD AND DEBRIS AT CHICKEN SPRINGS ROAD AND US 93. THEY ALSO STATED THAT ADOT WAS ON THE WAY TO CLEAR THE ROAD.

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

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 11.2 hours before the alert went out and 172 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, Flgstf/Belemont, AZ at 12:00Z on 2012-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 808 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2012-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
808 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
974 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

193 
WGUS55 KVEF 202314
FFWVEF
AZC015-210115-
/O.NEW.KVEF.FF.W.0134.120820T2314Z-120821T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
414 PM MST MON AUG 20 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTH CENTRAL MOHAVE COUNTY IN NORTHWEST ARIZONA...

* UNTIL 615 PM MST.

* AT 407 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR WIKIEUP. THE STORM
  PRODUCING VERY HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  WIKIEUP.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. NEVER TRY TO CROSS A FLOODED ROADWAY OR
WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
AREA ROADWAYS. FLASH FLOODING IS NATURES NUMBER ONE KILLER. TO ESCAPE
RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO CROSS A FLOODED
ROADWAY OR WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3482 11354 3462 11350 3461 11367 3479 11371

$$

ASG
3 follow-up statements
124 
WGUS75 KVEF 202331
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
431 PM MST MON AUG 20 2012

AZC015-210115-
/O.CON.KVEF.FF.W.0134.000000T0000Z-120821T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
431 PM MST MON AUG 20 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM MST FOR SOUTH
CENTRAL MOHAVE COUNTY...

AT 424 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A THUNDERSTORM PRODUCING VERY HEAVY RAIN. AN AUTOMATED RAIN 
GAUGE IN WIKIEUP HAS REPORTED 1.10 INCHES OF RAIN IN A 30 MINUTE 
PERIOD. THIS STORM WAS LOCATED NEAR WIKIEUP. THE THUNDERSTORM WITH 
EXCESSIVE RAIN WAS NEARLY STATIONARY.

LOCATIONS IMPACTED INCLUDE...
WIKIEUP

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
AREA ROADWAYS. FLASH FLOODING IS NATURES NUMBER ONE KILLER. TO ESCAPE
RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO CROSS A FLOODED
ROADWAY OR WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3482 11354 3462 11350 3461 11367 3479 11371

$$

ASG
949 
WGUS75 KVEF 210026
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
526 PM MST MON AUG 20 2012

AZC015-210115-
/O.CON.KVEF.FF.W.0134.000000T0000Z-120821T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
526 PM MST MON AUG 20 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM MST FOR SOUTH
CENTRAL MOHAVE COUNTY...

AT 516 PM MST...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH 
FLOODING FROM A THUNDERSTORM IN WIKIEUP. LAW ENFORCEMENT ALSO STATED 
THAT THERE WAS LOT OF MUD AND DEBRIS AT CHICKEN SPRINGS ROAD AND 
HIGHWAY 93. HEAVY RAIN IN WIKIEUP HAS DIMINISHED...BUT THE 
ADDITIONAL THREAT OF SIGNIFICANT RUNOFF WILL LIKELY CONTINUE THROUGH 
600 PM. 

LOCATIONS IMPACTED INCLUDE...
WIKIEUP.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED IN WASHES...LOW WATER CROSSINGS AND ON
AREA ROADWAYS. FLASH FLOODING IS NATURES NUMBER ONE KILLER. TO ESCAPE
RISING WATER...MOVE TO HIGHER GROUND. NEVER TRY TO CROSS A FLOODED
ROADWAY OR WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3482 11354 3462 11350 3461 11367 3479 11371

$$

ASG
438 
WGUS75 KVEF 210111
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
611 PM MST MON AUG 20 2012

AZC015-210120-
/O.EXP.KVEF.FF.W.0134.000000T0000Z-120821T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-
611 PM MST MON AUG 20 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 615 PM MST FOR SOUTH
CENTRAL MOHAVE COUNTY...

A NEW THUNDERSTORM HAS DEVELOPED OVER THE AREA THAT HAS ALEADY 
RECEIVED FLOODING. THIS WARNING WAS REPLACED WITH A NEW WARNING FOR 
THE SAME AREA. 

LAT...LON 3482 11354 3462 11350 3461 11367 3479 11371

$$

ASG

The office that day

Everything else NWS Las Vegas, NV issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 2:24 PM MSTFlash Flood WarningVEFMohave75 min
Aug 20, 2:34 PM MSTSevere Thunderstorm WarningVEFMohave41 min
Aug 20, 2:42 PM MSTFlash Flood WarningVEFMohave2 hr
Aug 20, 3:20 PM MSTFlash Flood WarningVEFMohave98 min

Nearby

Flash Flood Warnings in Arizona, 2012Every flash flood warning in 2012

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.