Alert archive / California / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 21, NWS Las Vegas, NV

July 23, 2012San Bernardino County, California

NWS Las Vegas, NV issued this severe thunderstorm warning at Jul 23, 2012, 1:54 PM PDT for San Bernardino County, California. It was in force for 66 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
Jul 23, 2012, 1:54 PM PDT (20:54 UTC)
Expired
Jul 23, 2012, 3:00 PM PDT
In force
66 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon

County San Bernardino County, CA

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 8.9 hours before the alert went out and 200 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 2012-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 177 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 2012-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
177 J/kg
Mixed-layer CIN
-137 J/kg
Mixed-layer LCL
2252 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
-22 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.

974 
WUUS55 KVEF 232054
SVRVEF
CAC071-232200-
/O.NEW.KVEF.SV.W.0021.120723T2054Z-120723T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
154 PM PDT MON JUL 23 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL SAN BERNARDINO COUNTY IN SOUTHERN CALIFORNIA...

* UNTIL 300 PM PDT.

* AT 150 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 NEAR
  NEWBERRY MOUNTAIN RV PARK...OR 11 MILES EAST OF DAGGETT...AND WAS
  MOVING NORTHEAST AT 10 MPH.

* LOCATIONS IMPACTED INCLUDE...
  NEWBERRY MOUNTAIN RV PARK.

THIS INCLUDES INTERSTATE 40 BETWEEN MILE MARKERS 11 AND 28.

THIS INCLUDES INTERSTATE 15 BETWEEN MILE MARKERS 89 AND 101.

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.

THIS STORM IS CAPABLE OF PRODUCING LARGE HAIL THAT CAN CAUSE INJURY
AND DAMAGE PROPERTY. IN ADDITION...STRONG WINDS AND LIGHTNING ARE
LIKELY. LIGHTNING CAN KILL! TAKE SHELTER IN A STURDY BUILDING. IF IT
IS SAFE TO DO SO...TAKE APPROPRIATE ACTIONS TO PROTECT VEHICLES AND
PROPERTY.

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 3476 11666 3476 11672 3485 11684 3505 11666
      3486 11641 3474 11664
TIME...MOT...LOC 2053Z 221DEG 8KT 3486 11669

$$

JH
2 follow-up statements
084 
WWUS55 KVEF 232129
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
229 PM PDT MON JUL 23 2012

CAC071-232200-
/O.CON.KVEF.SV.W.0021.000000T0000Z-120723T2200Z/
SAN BERNARDINO CA-
229 PM PDT MON JUL 23 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM PDT
FOR CENTRAL SAN BERNARDINO COUNTY...

AT 225 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 AND DIME SIZE HAIL. 
THIS STORM WAS LOCATED NEAR NEWBERRY MOUNTAIN RV PARK...OR 17 MILES 
EAST OF DAGGETT...AND WAS MOVING NORTHEAST AT 10 MPH.

LOCATIONS IMPACTED INCLUDE...
MAINLY RURAL AREAS OF CENTRAL SAN BERNARDINO COUNTY.

THIS INCLUDES INTERSTATE 40 BETWEEN MILE MARKERS 20 AND 28.

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 3486 11673 3501 11660 3486 11641 3485 11643
      3476 11660
TIME...MOT...LOC 2128Z 221DEG 8KT 3487 11657

$$

JH
419 
WWUS55 KVEF 232155
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
255 PM PDT MON JUL 23 2012

CAC071-232204-
/O.EXP.KVEF.SV.W.0021.000000T0000Z-120723T2200Z/
SAN BERNARDINO CA-
255 PM PDT MON JUL 23 2012

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL SAN BERNARDINO COUNTY
WILL EXPIRE AT 300 PM PDT...

THIS INCLUDES INTERSTATE 40 BETWEEN MILE MARKERS 20 AND 28. THE 
THUNDERSTORM HAD WEAKENED AND THE THREAT OF LARGE HAIL AND DAMAGING 
WINDS HAS ENDED. THE STORM COULD STILL PRODUCE SMALL HAIL AND WIND 
GUSTS TO 40 MPH ALONG WITH HEAVY RAIN. 

LAT...LON 3486 11673 3501 11660 3486 11641 3485 11643
      3476 11660
TIME...MOT...LOC 2154Z 221DEG 8KT 3491 11652

$$

JH

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 11:17 AM PDTAreal Flood AdvisoryVEFInyo49 min
Jul 23, 11:47 AM PDTFlash Flood WarningVEFSan Bernardino2 hr
Jul 23, 12:05 PM PDTFlash Flood WarningVEFInyo115 min
Jul 23, 12:12 PM PDTSevere Thunderstorm WarningVEFSan Bernardino48 min
Jul 23, 12:18 PM PDTFlash Flood WarningVEFSan Bernardino117 min

Nearby

Severe Thunderstorm Warnings in California, 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.