Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 218, NWS Las Vegas, NV

October 11, 2012Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Oct 11, 2012, 6:45 PM PDT for 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
Oct 11, 2012, 6:45 PM PDT (01:45 UTC)
Expired
Oct 11, 2012, 8:45 PM PDT
In force
2 hr
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County Clark County, NV

The radar

The Las Vegas radar (KESX), 69 km from the middle of the area, began a volume at 01:48 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
Oct 11, 8:33 PM PDTFLASH FLOOD2 Ese Red Rock Canyon, NVSTATE ROUTE 159 WAS CLOSED AT THE RED ROCK CANYON SCENIC LOOP DRIVE DUE TO DEBRIS ON THE ROAD FROM FLOODWATERS.

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 00:00Z, 1.8 hours before the alert went out and 30 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 00:00Z on 2012-10-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 305 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 00:00Z on 2012-10-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.1939587897Sfc1 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
305 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
1141 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.3

Open this sounding in Storm Lab

The text

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

184 
WGUS55 KVEF 120145
FFWVEF
NVC003-120345-
/O.NEW.KVEF.FF.W.0218.121012T0145Z-121012T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
645 PM PDT THU OCT 11 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 845 PM PDT.

* AT 640 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED   
  TO INDICATE SHOWERS PRODUCING RAIN FROM RED ROCK CANYON TO SPRING  
  MOUNTAIN RANCH STATE PARK. THIS COMBINED WITH ANY HEAVY RAIN THAT  
  FELL EARLIER WILL RESULT IN RAPID FLOWS IN ANY WASHES AS WELL AS   
  SEVERAL INCHES OF FLOWING WATER ACROSS LOW SPOTS ON ROADS ALONG    
  WITH MUD AND ROCKS. LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH 
  FLOODING HAS TAKEN PLACE ON HIGHWAY 159 AT MILE MARKER 11 WHERE    
  SEVERAL INCHES OF WATER WERE FLOWING ACROSS THE ROAD ALONG WITH    
  DEBRIS. OTHER AREAS THAT COULD BE IMPACTED INCLUDE LOW SPOTS       
  ELSEWHERE ALONG HIGHWAY 159 NEAR RED ROCK CANYON AS WELL AS ON THE 
  RED ROCK CANYON SCENIC LOOP AND IN SPRING MOUNTAIN RANCH STATE     
  PARK.  

* LOCATIONS IMPACTED INCLUDE...
  RED ROCK CANYON...RED ROCK CANYON CAMPGROUND...ROCKY GAP           
  CAMPGROUND...SPRING MOUNTAIN RANCH STATE PARK AND BLUE DIAMOND.

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 3619 11553 3618 11537 3600 11537 3603 11550

$$

STACHELSKI
2 follow-up statements
420 
WGUS75 KVEF 120236
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
736 PM PDT THU OCT 11 2012

NVC003-120345-
/O.CON.KVEF.FF.W.0218.000000T0000Z-121012T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
736 PM PDT THU OCT 11 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM PDT FOR WEST
CENTRAL CLARK COUNTY...

AT 725 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED     
TO INDICATE SHOWERS PRODUCING RAIN FROM RED ROCK CANYON TO SPRING    
MOUNTAIN RANCH STATE PARK. THIS COMBINED WITH ANY HEAVY RAIN THAT    
FELL EARLIER WILL RESULT IN RAPID FLOWS IN ANY WASHES AS WELL AS     
SEVERAL INCHES OF FLOWING WATER ACROSS LOW SPOTS ON ROADS ALONG      
WITH MUD AND ROCKS. LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH   
FLOODING HAS TAKEN PLACE ON HIGHWAY 159 AT MILE MARKER 11 WHERE      
SEVERAL INCHES OF WATER WERE FLOWING ACROSS THE ROAD ALONG WITH      
DEBRIS. ARROYO ROAD IN BLUE DIAMOND HAD A FOOT OF WATER FLOWING 
ACROSS IT WITH DEBRIS ACCORDING TO LOCAL MEDIA REPORTS. OTHER AREAS 
THAT COULD BE IMPACTED INCLUDE LOW SPOTS ELSEWHERE ALONG HIGHWAY 159 
NEAR RED ROCK CANYON AS WELL AS ON THE RED ROCK CANYON SCENIC LOOP 
AND IN SPRING MOUNTAIN RANCH STATE PARK.  

LOCATIONS IMPACTED INCLUDE...
RED ROCK CANYON...RED ROCK CANYON CAMPGROUND...ROCKY GAP 
CAMPGROUND...SPRING MOUNTAIN RANCH AND BLUE DIAMOND.

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 3619 11553 3618 11537 3600 11537 3603 11550

$$

STACHELSKI
320 
WGUS75 KVEF 120342
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
842 PM PDT THU OCT 11 2012

NVC003-120351-
/O.EXP.KVEF.FF.W.0218.000000T0000Z-121012T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
842 PM PDT THU OCT 11 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 845 PM PDT FOR WEST CENTRAL
CLARK COUNTY...

HEAVY RAIN PRODUCING THUNDERSTORMS HAVE MOVED OUT OF THE AREA OF 
CLARK COUNTY BETWEEN RED ROCK CANYON AND THE TOWN OF BLUE DIAMOND. 
THEREFORE THE FLASH FLOOD WARNING FOR THIS AREA WILL BE ALLOWED TO 
EXPIRE.

LAT...LON 3619 11553 3618 11537 3600 11537 3603 11550

$$

STACHELSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 11, 5:25 PM PDTSevere Thunderstorm WarningVEFClark, Nye35 min
Oct 11, 5:52 PM PDTSevere Thunderstorm WarningVEFNye53 min
Oct 11, 7:56 PM PDTFlash Flood WarningVEFClark80 min
Oct 11, 8:12 PM PDTSevere Thunderstorm WarningVEFClark48 min
Oct 11, 8:21 PM PDTFlash Flood WarningVEFClark114 min
Oct 11, 8:57 PM PDTSevere Thunderstorm WarningVEFClark48 min
Oct 11, 9:07 PM PDTFlash Flood WarningVEFClark113 min
Oct 11, 9:40 PM PDTSevere Thunderstorm WarningVEFClark27 min
Oct 11, 10:15 PM PDTFlash Flood WarningVEFClark2 hr
Oct 11, 10:42 PM PDTFlash Flood WarningVEFClark94 min
Oct 12, 12:03 AM PDTFlash Flood WarningVEFNye87 min
Oct 12, 12:28 AM PDTSevere Thunderstorm WarningVEFLincoln32 min
Oct 12, 1:43 PM PDTFlash Flood WarningVEFClark2 hr

Nearby

Flash 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.