Alert archive / Nevada / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 1, NWS Las Vegas, NV

May 9, 2011Clark County, Nevada

NWS Las Vegas, NV issued this severe thunderstorm warning at May 9, 2011, 1:55 PM PDT for Clark County, Nevada. It was in force for 35 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 9, 2011, 1:55 PM PDT (20:55 UTC)
Expired: May 9, 2011, 2:30 PM PDT
In force: 35 min
Issued by: NWS Las Vegas, NV
Area: Storm-based polygon

County Clark County, NV

The radar

The Las Vegas radar (KESX), 125 km from the middle of the area, began a volume at 20:57 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.

What was reported inside it

Time	Report	Where	Remark
May 9, 2:07 PM PDT	HAIL 0.75	6 N Mormon Mesa (Mmtn2), NV	PUBLIC REPORTS LOTS OF SMALL HAIL WITH HAIL UP TO THREE QUARTER INCHES ALONG INTERSTATE 15 NORTH. TIME ESTIMATED BY RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 8.9 hours before the alert went out and 109 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 8 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 1248 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -7 m²/s²
0-3 km storm-relative helicity: -13 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.

267 
WUUS55 KVEF 092055
SVRVEF
NVC003-092130-
/O.NEW.KVEF.SV.W.0001.110509T2055Z-110509T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
155 PM PDT MON MAY 9 2011

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 230 PM PDT.

* AT 152 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED OVER
  NORTHEASTERN CLARK COUNTY...OR 13 MILES NORTHEAST OF MOAPA...AND
  MOVING NORTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL IMPACT INTERSTATE 15 BETWEEN MILE 
  MARKERS 96 AND 115.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE 
IMMEDIATELY FOR DAMAGING WINDS UP TO 60 MPH...SMALL HAIL...AND 
DEADLY CLOUD TO GROUND LIGHTNING. WINDS OF 60 MPH OR GREATER CAN 
BRING DOWN TREES AND CAUSE BLOWING DUST AND DEBRIS...REDUCING 
VISIBILITY AND POSSIBLY RESULTING IN INJURY AND PROPERTY DAMAGE. 
ROOFS OF MOBILE HOMES AND OUTBUILDINGS COULD BE DAMAGED...AND MINOR 
DAMAGE TO WELL BUILT HOMES AND STRUCTURES COULD OCCUR.

PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY INSIDE A STURDY
BUILDING BUT AWAY FROM WINDOWS...SUCH AS AN INTERIOR ROOM ON THE
LOWEST FLOOR OF A HOME OR BUSINESS. IF YOU ARE OUTSIDE AND CANNOT GET
TO A SAFE SHELTER WITH WALLS AND A DOOR...TAKE SHELTER IN A HARDTOP
VEHICLE.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST EMERGENCY MANAGEMENT
OFFICE OR LAW ENFORCEMENT AGENCY. ASK THEM TO RELAY YOUR REPORT TO
THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN LAS VEGAS.

&&

LAT...LON 3684 11453 3684 11426 3674 11416 3666 11434
      3666 11442 3667 11447 3677 11455
TIME...MOT...LOC 2054Z 236DEG 15KT 3675 11439

$$

GIBBS/MORGAN

2 follow-up statements

781 
WWUS55 KVEF 092113
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
213 PM PDT MON MAY 9 2011

NVC003-092130-
/O.CON.KVEF.SV.W.0001.000000T0000Z-110509T2130Z/
CLARK NV-
213 PM PDT MON MAY 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 PM PDT
FOR NORTHEASTERN CLARK COUNTY...

AT 207 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED OVER NORTHEASTERN CLARK COUNTY...OR 12 MILES NORTHEAST OF 
MOAPA...MOVING NORTHEAST AT 10 MPH.  

THE SEVERE THUNDERSTORM WILL IMPACT INTERSTATE 15 BETWEEN MILE 
MARKERS 98 AND 109.

LAT...LON 3669 11428 3666 11434 3666 11442 3668 11447
      3672 11449 3677 11451 3683 11446 3684 11426
TIME...MOT...LOC 2112Z 235DEG 11KT 3675 11441

$$

JGG/CM

319 
WWUS55 KVEF 092129
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
229 PM PDT MON MAY 9 2011

NVC003-092138-
/O.EXP.KVEF.SV.W.0001.000000T0000Z-110509T2130Z/
CLARK NV-
229 PM PDT MON MAY 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CLARK COUNTY WILL
EXPIRE AT 230 PM PDT...

RADAR INDICATED THE STORM WHICH PROMPTED THE WARNING HAD WEAKENED 
AND WAS NO LONGER SEVERE. SMALL HAIL AND GUSTY WINDS WILL REMAIN 
POSSIBLE. HEAVY RAIN HAS FALLEN AND WILL CONTINUE TO BE POSSIBLE. 
MOTORISTS SHOULD BE ALERT FOR PONDING WATER ON AREA ROADWAYS.

LAT...LON 3669 11428 3666 11434 3666 11442 3668 11447
      3672 11449 3677 11451 3683 11446 3684 11426
TIME...MOT...LOC 2128Z 235DEG 11KT 3678 11436

$$

JGG/CM

Nearby

Severe Thunderstorm Warnings in Nevada, 2011 Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.