Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 165, NWS Las Vegas, NV

August 22, 2012Mohave County, Arizona; Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Aug 22, 2012, 3:43 PM MST for Mohave County, Arizona; Clark County, Nevada. It was in force for 2 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
Aug 22, 2012, 3:43 PM MST (22:43 UTC)
Expired
Aug 22, 2012, 5:45 PM MST
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

Counties Mohave County, AZ, Clark County, NV

The radar

The Las Vegas radar (KESX), 43 km from the middle of the area, began a volume at 22:43 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 22, 4:00 PM MSTFLASH FLOOD2 N Valley Of Fire Stat, NVWHITE DOME ROAD WAS UNDERCUT AND MOST OF IT WAS COMPLETELY WASHED OUT. MUD AND DEBRIS WAS OBSERVED OVER ROADS AT 10 DIFFERENT SPOTS WITHIN VALLEY OF FIRE STATE PARK.

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

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 10.7 hours before the alert went out and 75 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, Las Vegas, NV at 12:00Z on 2012-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 296 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, Las Vegas, NV at 12:00Z on 2012-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 103 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
296 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
1290 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
103 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.4

Open this sounding in Storm Lab

The text

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

231 
WGUS55 KVEF 222243
FFWVEF
AZC015-NVC003-230045-
/O.NEW.KVEF.FF.W.0165.120822T2243Z-120823T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
343 PM PDT WED AUG 22 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EXTREME WEST CENTRAL MOHAVE COUNTY IN NORTHWEST ARIZONA...
  CENTRAL CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 545 PM PDT/545 PM MST/.

* AT 338 PM MST...ALTHOUGH RAIN HAS RECENTLY DECREASED OVER THE PAST 
HOUR NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATES ADDITIONAL 
STORMS MOVING EAST AND SOUTH OF THE LAS VEGAS VALLEY FROM SLOAN TO 
WILLOW BEACH AND NORTH TO THE VALLEY OF FIRE STATE PARK...EXTENDING 
EAST TO OVERTON BEACH. THESE ADDITIONAL STORMS WILL RESULT IN 
CONTINUED FLASH FLOODING OVER THE WARNED AREA. THIS NEW WARNING IS A 
CONTINUATION OF THE WARNING PREVIOUSLY IN EFFECT.

LOCATIONS IMPACTED INCLUDE...BOULDER CITY...LAS VEGAS 
BAY...OVERTON...CALLVILLE BAY...CALLVILLE BAY CAMPGROUND...LAS VEGAS 
BAY CAMPGROUND...ECHO BAY CAMPGROUND...ECHO BAY...VALLEY OF FIRE 
STATE PARK...VALLEY OF FIRE AND OVERTON BEACH.

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.

CAMPERS AND HIKERS SHOULD BE ALERT TO THE POSSIBILITY OF RAPIDLY
RISING WATER AND BE PREPARED TO MOVE QUICKLY TO HIGHER GROUND IF
FLASH FLOODING IS OBSERVED.

&&

LAT...LON 3590 11514 3596 11491 3654 11489 3654 11425
      3614 11426 3584 11456 3583 11515

$$

KENNEDY
2 follow-up statements
788 
WGUS75 KVEF 222356
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
456 PM PDT WED AUG 22 2012

AZC015-NVC003-230045-
/O.CON.KVEF.FF.W.0165.000000T0000Z-120823T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-CLARK NV-
456 PM PDT WED AUG 22 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM PDT/545 PM
MST/ FOR CENTRAL CLARK AND EXTREME WEST CENTRAL MOHAVE COUNTIES...

AT 445 PM MST...LIGHT TO MODERATE RAIN WILL CONTINUE TO FALL EAST 
AND SOUTH OF THE LAS VEGAS VALLEY FROM SLOAN TO WILLOW BEACH AND 
NORTH TO THE VALLEY OF FIRE STATE PARK...EXTENDING EAST TO OVERTON 
BEACH. THIS RAINFALL IN ADDITION TO THE SIGNIFICANT AMOUNTS THAT 
HAVE ALREADY FALLEN WILL RESULT IN CONTINUED FLASH FLOODING OVER THE 
WARNED AREA. 

MULTIPLE STREETS IN BOULDER CITY ARE CLOSED DUE TO WATER             
AND DEBRIS...AND NATIONAL PARK SERVICE EMPLOYEES HAVE REPORTED 
MULTIPLE ROADS INSIDE VALLEY OF FIRE STATE PARK ARE CLOSED DUE TO 
FLOODING AND 6 TO 8 INCHES OF WATER RUNNING ACROSS NORTHSHORE ROAD 
AT MILE MARKER 7. 

LOCATIONS IMPACTED INCLUDE...BOULDER CITY...LAS VEGAS 
BAY...OVERTON...CALLVILLE BAY...CALLVILLE BAY CAMPGROUND...LAS VEGAS 
BAY CAMPGROUND...ECHO BAY CAMPGROUND...ECHO BAY...VALLEY OF FIRE 
STATE PARK...VALLEY OF FIRE AND OVERTON BEACH.

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 3590 11514 3596 11491 3654 11489 3654 11425
      3614 11426 3584 11456 3583 11515

$$

KENNEDY
184 
WGUS75 KVEF 230041
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
541 PM PDT WED AUG 22 2012

AZC015-NVC003-230047-
/O.EXP.KVEF.FF.W.0165.000000T0000Z-120823T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MOHAVE AZ-CLARK NV-
541 PM PDT WED AUG 22 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 545 PM PDT/545 PM MST/ FOR 
CENTRAL CLARK AND EXTREME WEST CENTRAL MOHAVE COUNTIES...

WHILE ADDITIONAL RAINFALL IS LIKELY THE REMAINDER OF THE DAY AND 
OVERNIGHT EAST AND SOUTH OF THE LAS VEGAS VALLEY FROM BOULDER CITY 
AND WILLOW BEACH NORTH TO VALLEY OF FIRE STATE PARK. THE THREAT OF 
SIGNIFICANT ADDITIONAL RAINFALL HAS ENDED...AND THE FLASH FLOOD 
WARNING WILL BE ALLOWED TO EXPIRE.

IT WILL LIKELY BE SEVERAL HOURS BEFORE RUNNING WATER IN WASHES BEGIN 
TO RECEDE...AND ROADWAYS...INTERSECTIONS...AND LOCALIZED AREAS PRONE 
TO FLOODING WILL LIKELY STILL BE IMPACTED THROUGH 700 PM THIS 
EVENING.

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

LAT...LON 3590 11514 3596 11491 3654 11489 3654 11425
      3614 11426 3584 11456 3583 11515

$$

KENNEDY

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 7:18 PM MSTAreal Flood AdvisoryVEFMohave87 min
Aug 21, 11:32 PM MSTAreal Flood AdvisoryVEFMohave118 min
Aug 22, 12:12 PM MSTFlash Flood WarningVEFMohave4 hr
Aug 22, 2:40 PM MSTAreal Flood AdvisoryVEFMohave6 hr
Aug 21, 6:10 PM MSTFlash Flood WarningVEFClark, Lincoln2 hr
Aug 21, 6:47 PM MSTFlash Flood WarningVEFLincoln118 min
Aug 22, 12:12 AM MSTFlash Flood WarningVEFClark2 hr
Aug 22, 2:35 AM MSTFlash Flood WarningVEFClark115 min
Aug 22, 8:22 AM MSTAreal Flood AdvisoryVEFClark9 hr
Aug 22, 9:19 AM MSTAreal Flood AdvisoryVEFClark, Lincoln, Nye3 hr
Aug 22, 9:20 AM MSTFlash Flood WarningVEFClark101 min
Aug 22, 9:34 AM MSTFlash Flood WarningVEFClark116 min
Aug 22, 9:59 AM MSTFlash Flood WarningVEFClark59 min
Aug 22, 10:05 AM MSTFlash Flood WarningVEFEsmeralda76 min
Aug 22, 10:53 AM MSTFlash Flood WarningVEFClark4 hr
Aug 22, 12:33 PM MSTFlash Flood WarningVEFClark117 min

Nearby

Flash Flood Warnings in Arizona, 2012Flash Flood Warnings in Nevada, 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.