Alert archive / Nevada / Flash Flood Warnings in 2011

Flash Flood Warning 18, NWS Las Vegas, NV

July 5, 2011Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Jul 5, 2011, 3:09 PM PDT for Clark County, Nevada. It was in force for 2 hr. 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 5, 2011, 3:09 PM PDT (22:09 UTC)
Expired
Jul 5, 2011, 5:15 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), 68 km from the middle of the area, began a volume at 22:12 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, 10.2 hours before the alert went out and 35 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 2011-07-05Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Las Vegas, NV at 12:00Z on 2011-07-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
2419 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
137 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.

237 
WGUS55 KVEF 052209
FFWVEF
NVC003-060015-
/O.NEW.KVEF.FF.W.0018.110705T2209Z-110706T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
309 PM PDT TUE JUL 5 2011

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 515 PM PDT.

* AT 303 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR MOUNTAIN SPRINGS...OR 8
  MILES SOUTH OF RED ROCK CANYON. THE STORM PRODUCING VERY HEAVY RAIN
  WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...MOUNTAIN SPRINGS AND PORTIONS OF 
HIGHWAY 160 ESPECIALLY OVER MOUNTAIN SPRINGS PASS.

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 3611 11553 3612 11549 3608 11545 3600 11543
      3599 11549 3602 11555

$$

JENSEN
1 follow-up statement
166 
WGUS75 KVEF 060011
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
511 PM PDT TUE JUL 5 2011

NVC003-060020-
/O.EXP.KVEF.FF.W.0018.000000T0000Z-110706T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
511 PM PDT TUE JUL 5 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 515 PM PDT FOR WEST CENTRAL
CLARK COUNTY...

THUNDERSTORMS HAVE MOVED OUT OF THE AREA AND ALTHOUGH LIGHT RAIN MAY 
BE SEEN INTO THE EVENING...NO ADDITIONAL FLOODING IS EXPECTED.

LAT...LON 3611 11553 3612 11549 3608 11545 3600 11543
      3599 11549 3602 11555

$$

JENSEN

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 5, 12:14 PM PDTFlash Flood WarningVEFClark76 min
Jul 5, 12:54 PM PDTSevere Thunderstorm WarningVEFClark36 min
Jul 5, 1:12 PM PDTFlash Flood WarningVEFClark2 hr
Jul 5, 2:01 PM PDTSevere Thunderstorm WarningVEFClark33 min
Jul 5, 2:21 PM PDTFlash Flood WarningVEFClark114 min
Jul 5, 3:01 PM PDTFlash Flood WarningVEFClark89 min
Jul 5, 3:46 PM PDTAreal Flood AdvisoryVEFClark, Esmeralda, Lincoln, Nye119 min
Jul 5, 4:10 PM PDTFlash Flood WarningVEFClark110 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.