Alert archive / Nevada / Flash Flood Warnings in 2011

Flash Flood Warning 95, NWS Las Vegas, NV

September 14, 2011Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Sep 14, 2011, 4:35 PM PDT for Clark County, Nevada. It was in force for 55 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
Sep 14, 2011, 4:35 PM PDT (23:35 UTC)
Expired
Sep 14, 2011, 5:30 PM PDT
In force
55 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Flood severity
None

County Clark County, NV

The radar

The Las Vegas radar (KESX), 91 km from the middle of the area, began a volume at 23:38 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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 11.6 hours before the alert went out and 237 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 2011-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 224 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 2011-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 square meters per square second.19395878Sfc1 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
224 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
729 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

292 
WGUS55 KVEF 142335
FFWVEF
NVC003-150030-
/O.NEW.KVEF.FF.W.0095.110914T2335Z-110915T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
435 PM PDT WED SEP 14 2011

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 530 PM PDT.

* AT 425 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER EXTREME EAST CENTRAL CLARK
  COUNTY...OR 27 MILES SOUTHEAST OF OVERTON. THE STORM PRODUCING VERY
  HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...THE COTTONWOOD WASH ROAD LEADING TO
  DEVILS COVE.

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 TWITTER #NWSVEGAS.

&&

LAT...LON 3630 11418 3629 11409 3626 11405 3620 11405
      3618 11407 3612 11412 3622 11421

$$

JENSEN
2 follow-up statements
427 
WGUS75 KVEF 142357
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
457 PM PDT WED SEP 14 2011

NVC003-150030-
/O.CON.KVEF.FF.W.0095.000000T0000Z-110915T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
457 PM PDT WED SEP 14 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM PDT FOR EAST
CENTRAL CLARK COUNTY...

AT 447 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A THUNDERSTORM PRODUCING HEAVY RAIN.  THIS STORM WAS 
LOCATED OVER EXTREME EAST CENTRAL CLARK COUNTY...OR 28 MILES 
SOUTHEAST OF OVERTON. THE THUNDERSTORM WITH EXCESSIVE RAIN WAS NEARLY
STATIONARY.

LOCATIONS IMPACTED INCLUDE...THE COTTONWOOD WASH ROAD LEADING TO   
DEVILS COVE ON LAKE MEAD.

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 TWITTER #NWSVEGAS.

&&

LAT...LON 3630 11418 3629 11409 3626 11405 3620 11405
      3618 11407 3612 11412 3622 11421

$$

JENSEN
236 
WGUS75 KVEF 150026
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
526 PM PDT WED SEP 14 2011

NVC003-150033-
/O.EXP.KVEF.FF.W.0095.000000T0000Z-110915T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
526 PM PDT WED SEP 14 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 530 PM PDT FOR EAST CENTRAL
CLARK COUNTY...

THE POTENTIAL FOR HEAVY RAINFALL PRODUCING FLASH FLOODING HAS ENDED 
AS THUNDERSTORMS HAVE DECREASED OVER THE COTTONWOOD WASH ROAD 
LEADING TO DEVILS COVE IN EXTREME EASTERN CLARK COUNTY. 

HOWEVER WATER IS LIKELY FLOWING IN THE NORMALLY DRY WASH. TRAVELERS 
IN THE AREA SHOULD BE AWARE OF THIS FLOWING WATER AND BE ESPECIALLY 
CAUTIOUS AT LOW WATER CROSSINGS


LAT...LON 3630 11418 3629 11409 3626 11405 3620 11405
      3618 11407 3612 11412 3622 11421

$$

JENSEN

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 14, 1:19 PM PDTFlash Flood WatchVEFClark, Lincoln, Nye7 hr
Sep 14, 1:27 PM PDTAreal Flood AdvisoryVEFClark111 min
Sep 14, 1:52 PM PDTFlash Flood WarningVEFClark92 min
Sep 14, 3:13 PM PDTAreal Flood AdvisoryVEFClark2 hr
Sep 14, 4:02 PM PDTAreal Flood AdvisoryVEFLincoln118 min

Nearby

Flash Flood Warnings in Nevada, 2011Every flash flood warning in 2011

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.