Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 110, NWS Las Vegas, NV

August 9, 2012Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Aug 9, 2012, 6:14 PM PDT for Clark County, Nevada. It was in force for 37 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
Aug 9, 2012, 6:14 PM PDT (01:14 UTC)
Expired
Aug 9, 2012, 6:51 PM PDT
In force
37 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), 36 km from the middle of the area, began a volume at 01:13 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 00:00Z, 1.2 hours before the alert went out and 59 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 2012-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2012-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
5451 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
16 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.

046 
WGUS55 KVEF 100114
FFWVEF
NVC003-100315-
/O.NEW.KVEF.FF.W.0110.120810T0114Z-120810T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
614 PM PDT THU AUG 9 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 815 PM PDT.

* AT 607 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR ANTHEM...OR 8 MILES       
SOUTHWEST OF HENDERSON...MOVING NORTH AT 5 MPH.  THE ANTHEM 
DETENTION BASIN IS REPORT A HALF OF RAIN IN 15 MINUTES.

* LOCATIONS IMPACTED INCLUDE...
  ANTHEM...SEVEN HILLS...SILVERADO RANCH...GREEN VALLEY AND SAM BOYD
  STADIUM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. 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 3602 11516 3610 11501 3590 11502 3587 11515

$$

BORDEN
1 follow-up statement
749 
WGUS75 KVEF 100151
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
651 PM PDT THU AUG 9 2012

NVC003-100156-
/O.CAN.KVEF.FF.W.0110.000000T0000Z-120810T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
651 PM PDT THU AUG 9 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR CENTRAL CLARK 
COUNTY...THE THUNDERSTORM THAT PROMPTED THE WARNING OVER THE ANTHEM 
AREA HAS DISSIPATED.  THE ANTHEM DETENTION BASIN REPORTED SIX TENTHS 
OF AN INCH OF RAIN IN LESS THAN ONE HOUR.  THE RUNOFF FROM THIS 
STORM SHOULD BE CONTAINED TO THE DETENTION BASIN.  MINOR PONDING OF 
WATER IS STILL POSSIBLE THROUGH 7:30 PM.     

LAT...LON 3602 11516 3610 11501 3590 11502 3587 11515

$$

BORDEN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 7:06 PM PDTDust Storm WarningVEFClark115 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.