Alert archive / Nevada / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 57, NWS Las Vegas, NV

September 11, 2012Clark County, Nevada; Mohave County, Arizona

NWS Las Vegas, NV issued this severe thunderstorm warning at Sep 11, 2012, 2:16 PM PDT for Clark County, Nevada; Mohave County, Arizona. It was in force for 44 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 11, 2012, 2:16 PM PDT (21:16 UTC)
Expired
Sep 11, 2012, 3:00 PM PDT
In force
44 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon

Counties Mohave County, AZ, Clark County, NV

The radar

The Las Vegas radar (KESX), 31 km from the middle of the area, began a volume at 21:18 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, 9.3 hours before the alert went out and 89 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 2012-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 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 2012-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
2 J/kg
Mixed-layer CIN
-171 J/kg
Mixed-layer LCL
1725 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
37 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.

758 
WUUS55 KVEF 112116
SVRVEF
AZC015-NVC003-112200-
/O.NEW.KVEF.SV.W.0057.120911T2116Z-120911T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
216 PM PDT TUE SEP 11 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME WEST CENTRAL MOHAVE COUNTY IN NORTHWEST ARIZONA...
  CENTRAL CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 300 PM PDT/300 PM MST/.

* AT 214 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR RAILROAD PASS...OR NEAR
  BOULDER CITY...AND WAS MOVING EAST AT 15 MPH.

* LOCATIONS IMPACTED INCLUDE...
  BOULDER CITY AND HOOVER DAM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM IS CAPABLE OF PRODUCING DAMAGING WINDS WHICH CAN BRING
DOWN TREES AND POWER LINES AND CAUSE SIGNIFICANT BLOWING DUST AND
DEBRIS. IN ADDITION...HAIL AND LIGHTNING ARE LIKELY. LIGHTNING CAN
KILL! TAKE COVER IN A SUBSTANTIAL SHELTER AND STAY AWAY FROM WINDOWS
UNTIL THE STORM PASSES.

REPORT SEVERE WEATHER BY POSTING YOUR REPORT TO THE LAS VEGAS
NATIONAL WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER
HASHTAG...NWSVEGAS.

&&

LAT...LON 3599 11449 3575 11456 3588 11503 3606 11498
TIME...MOT...LOC 2116Z 284DEG 15KT 3595 11490

$$

MORGAN
2 follow-up statements
388 
WWUS55 KVEF 112133
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
233 PM MST TUE SEP 11 2012

AZC015-NVC003-112200-
/O.CON.KVEF.SV.W.0057.000000T0000Z-120911T2200Z/
MOHAVE AZ-CLARK NV-
233 PM MST TUE SEP 11 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM
MST/300 PM PDT/ FOR CENTRAL CLARK AND EXTREME WEST CENTRAL MOHAVE
COUNTIES...

AT 231 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH.  THIS STORM WAS LOCATED JUST EAST OF BOULDER 
CITY...AND WAS MOVING EAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE...
HOOVER DAM AND WILLOW BEACH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM IS CAPABLE OF PRODUCING DAMAGING WINDS WHICH CAN BRING
DOWN TREES AND POWER LINES AND CAUSE SIGNIFICANT BLOWING DUST AND
DEBRIS. IN ADDITION...HAIL AND LIGHTNING ARE LIKELY. LIGHTNING CAN
KILL! TAKE COVER IN A SUBSTANTIAL SHELTER AND STAY AWAY FROM WINDOWS
UNTIL THE STORM PASSES.

REPORT SEVERE WEATHER BY POSTING YOUR REPORT TO THE LAS VEGAS
NATIONAL WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER
HASHTAG...NWSVEGAS.

&&

LAT...LON 3605 11487 3599 11449 3575 11456 3585 11492
TIME...MOT...LOC 2133Z 284DEG 15KT 3593 11482

$$

MORGAN
294 
WWUS55 KVEF 112151
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
251 PM MST TUE SEP 11 2012

AZC015-NVC003-112200-
/O.EXP.KVEF.SV.W.0057.000000T0000Z-120911T2200Z/
MOHAVE AZ-CLARK NV-
251 PM MST TUE SEP 11 2012

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL CLARK AND EXTREME WEST
CENTRAL MOHAVE COUNTIES WILL EXPIRE AT 300 PM MST/300 PM PDT/...

AT 250 PM PDT...RADAR INDICATED THAT THE THUNDERSTORM SOUTHEAST OF 
BOULDER CITY HAD WEAKENED. THEREFORE...THE SEVERE THUNDERSTORM 
WARNING WILL BE ALLOWED TO EXPIRE.

PEOPLE IN WILLOW BEACH SHOULD BE PREPARED FOR WIND GUSTS OF 40 TO 50 
MPH FROM THIS STORM.

LAT...LON 3605 11487 3599 11449 3575 11456 3585 11492
TIME...MOT...LOC 2150Z 284DEG 15KT 3591 11474

$$

MORGAN

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 11, 3:24 AM PDTFlash Flood WarningVEFClark111 min
Sep 11, 4:52 AM PDTFlash Flood WarningVEFNye113 min
Sep 11, 8:28 AM PDTAreal Flood AdvisoryVEFLincoln3 hr
Sep 11, 11:33 AM PDTAreal Flood AdvisoryVEFClark3 hr
Sep 11, 12:32 PM PDTFlash Flood WarningVEFClark88 min
Sep 11, 1:44 PM PDTAreal Flood AdvisoryVEFClark27 min
Sep 11, 1:51 PM PDTFlash Flood WarningVEFClark114 min
Sep 11, 2:08 PM PDTFlash Flood WarningVEFClark93 min
Sep 11, 2:18 PM PDTFlash Flood WarningVEFClark4 hr
Sep 11, 3:39 PM PDTFlash Flood WarningVEFClark2 hr
Sep 11, 4:02 PM PDTFlash Flood WarningVEFClark118 min
Sep 10, 5:35 PM PDTFlash Flood WarningVEFMohave115 min
Sep 11, 5:05 AM PDTFlash Flood WarningVEFMohave65 min

Nearby

Severe Thunderstorm Warnings in Nevada, 2012Severe Thunderstorm Warnings in Arizona, 2012Every severe thunderstorm 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.