Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 191, NWS Las Vegas, NV

September 10, 2012Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Sep 10, 2012, 1:03 PM PDT for Clark 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
Sep 10, 2012, 1:03 PM PDT (20:03 UTC)
Expired
Sep 10, 2012, 3:00 PM PDT
In force
117 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), 97 km from the middle of the area, began a volume at 20:04 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, 8.1 hours before the alert went out and 11 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 2012-09-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 438 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 2012-09-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -10 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
438 J/kg
Mixed-layer CIN
-137 J/kg
Mixed-layer LCL
2077 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
0 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.

350 
WGUS55 KVEF 102003
FFWVEF
NVC003-102200-
/O.NEW.KVEF.FF.W.0191.120910T2003Z-120910T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
103 PM PDT MON SEP 10 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 300 PM PDT.

* AT 1256 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR MAHOGANY GROVE   
  CAMPGROUND AND THE INTERSECTION OF DEER CREEK ROAD AND LEE CANYON
  ROAD IN THE SPRING MOUNTAINS. THE THUNDERSTORM PRODUCING HEAVY 
  RAIN IS NEAR STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  COMMUNITIES IN LEE CANYON...LEE CANYON ROAD AND NEARBY SECTIONS
  OF DEER CREEK ROAD.

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 3632 11571 3640 11561 3632 11557 3629 11562

$$

JA
2 follow-up statements
589 
WGUS75 KVEF 102018
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
118 PM PDT MON SEP 10 2012

NVC003-102200-
/O.CON.KVEF.FF.W.0191.000000T0000Z-120910T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
118 PM PDT MON SEP 10 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 300 PM PDT FOR WEST
CENTRAL CLARK COUNTY...

THE NEVADA DIVISION OF FORESTRY REPORTED FLASH FLOODING WAS 
OCCURRING IN LEE CANYON. SOME ROADS WERE BECOMING IMPASSABLE AND 
WASHES IN THE AREA WILL BE RUNNING HIGH.

THE THUNDERSTORM PRODUCING HEAVY RAINFALL WAS STILL IN THE VICINITY 
OF THE INTERSECTION OF LEE CANYON AND DEER CREEK ROADS. THE STORM 
WAS NEARLY STATIONARY BUT DOPPLER RADAR INDICATED NEW STORM 
DEVELOPMENT WAS OCCURRING TOWARD KYLE CANYON ROAD AT 115 PM PDT.

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 3632 11571 3640 11561 3632 11557 3629 11562

$$

JA
943 
WGUS75 KVEF 102156
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
256 PM PDT MON SEP 10 2012

NVC003-102201-
/O.EXP.KVEF.FF.W.0191.000000T0000Z-120910T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
256 PM PDT MON SEP 10 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 300 PM PDT FOR WEST CENTRAL
CLARK COUNTY...

THE CLARK COUNTY DEPARTMENT OF PARKS AND RECREATION REPORTED THAT 
FLOODING HAD RECEDED IN LEE CANYON BUT SOME DEBRIS MAY STILL BE 
OBSERVED ON DEER CREEK ROAD BEFORE ROAD CREWS CAN CLEAR IT. HEAVY 
RAIN ENDED BEFORE 2 PM AND NO ADDTIONAL HEAVY RAIN IS EXPECTED IN 
THE IMMEDIATE FUTURE. THE FLASH FLOOD WARNING FOR LEE CANYON AND 
NEARBY SECTIONS OF DEER CREEK ROAD HAS BEEN ALLOWED TO EXPIRE.

LAT...LON 3632 11571 3640 11561 3632 11557 3629 11562

$$

JA

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 2:20 PM PDTFlash Flood WarningVEFClark115 min
Sep 10, 4:52 PM PDTAreal Flood AdvisoryVEFLincoln38 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.