Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 76, NWS Las Vegas, NV

July 31, 2012Clark County, Nye County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Jul 31, 2012, 2:33 PM PDT for Clark County, Nye County, Nevada. It was in force for 117 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 31, 2012, 2:33 PM PDT (21:33 UTC)
Expired
Jul 31, 2012, 4:30 PM PDT
In force
117 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

Counties Clark County, NV, Nye County, NV

The radar

The Las Vegas radar (KESX), 91 km from the middle of the area, began a volume at 21:35 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.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 9.6 hours before the alert went out and 44 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 2012-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 121 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 2012-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -5 square meters per square second.1939Sfc1 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
121 J/kg
Mixed-layer CIN
-75 J/kg
Mixed-layer LCL
1334 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
-43 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.

056 
WGUS55 KVEF 312133
FFWVEF
NVC003-023-312330-
/O.NEW.KVEF.FF.W.0076.120731T2133Z-120731T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
233 PM PDT TUE JUL 31 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 430 PM PDT.

* AT 226 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER EXTREME WEST CENTRAL CLARK
  COUNTY...OR 10 MILES SOUTHEAST OF PAHRUMP...MOVING SOUTHWEST AT 5
  MPH.

* LOCATIONS IMPACTED INCLUDE...
  STATE ROUTE 160 BETWEEN MILE MARKERS 37 AND 45 AND THE TECOPA
  TURNOFF ON THE OLD SPANISH TRAIL HIGHWAY.

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 3593 11580 3608 11599 3621 11582 3610 11564

$$

JA
2 follow-up statements
367 
WGUS75 KVEF 312236
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
336 PM PDT TUE JUL 31 2012

NVC003-023-312330-
/O.CON.KVEF.FF.W.0076.000000T0000Z-120731T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-NYE NV-
336 PM PDT TUE JUL 31 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 PM PDT FOR
EXTREME SOUTH CENTRAL NYE AND EXTREME WEST CENTRAL CLARK COUNTIES...

AT 330 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
HEAVY RAIN WAS DISSIPATING FROM THE THUNDERSTORM THAT WAS 15 MILES 
SOUTHEAST OF PAHRUMP. HOWEVER...UP TO AN INCH OF RAINFALL WAS 
ESTIMATED TO HAVE FALLEN FROM THIS STORM. THIS WILL LIKLEY PRODUCE
FLASH FLOODING UNTIL 430 PM ALONG STATE ROUTE 160 BETWEEN MILE 
MARKERS 38 AND 45 AND ALSO THE TECOPA TURNOFF AND SECTIONS OF THE 
OLD SPANISH TRAIL HIGHWAY TOWARD CHARLESTON VIEW.

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 3617 11584 3610 11573 3596 11584 3605 11596

$$

JA
876 
WGUS75 KVEF 312326
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
426 PM PDT TUE JUL 31 2012

NVC003-023-312332-
/O.EXP.KVEF.FF.W.0076.000000T0000Z-120731T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-NYE NV-
426 PM PDT TUE JUL 31 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 430 PM PDT FOR EXTREME
SOUTH CENTRAL NYE AND EXTREME WEST CENTRAL CLARK COUNTIES...

NO HEAVY RAIN HAS OCCURRED SOUTHEAST OF PAHRUMP NEAR THE TECOPA 
CUTOFF SINCE 3 PM AND RUNOFF HAS LIKELY RECEDED. THE FLASH FLOODING 
WARNING WILL BE ALLOWED TO EXPIRE ON SCHEDULE.

LAT...LON 3617 11584 3610 11573 3596 11584 3605 11596

$$

JA

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 2:29 AM PDTFlash Flood WatchVEFClark19 hr
Jul 31, 6:39 AM PDTAreal Flood AdvisoryVEFClark51 min
Jul 31, 2:42 PM PDTFlash Flood WarningVEFClark3 hr
Jul 31, 4:37 PM PDTFlash Flood WarningVEFClark113 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.