Alert archive / California / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 20, NWS Las Vegas, NV

July 23, 2012San Bernardino County, California

NWS Las Vegas, NV issued this severe thunderstorm warning at Jul 23, 2012, 12:12 PM PDT for San Bernardino County, California. It was in force for 48 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, 12:12 PM PDT (19:12 UTC)
Expired
Jul 23, 2012, 1:00 PM PDT
In force
48 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon

County San Bernardino County, CA

The radar

The Las Vegas radar (KESX), 80 km from the middle of the area, began a volume at 19:15 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, 7.2 hours before the alert went out and 82 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.

326 
WUUS55 KVEF 231912
SVRVEF
CAC071-232000-
/O.NEW.KVEF.SV.W.0020.120723T1912Z-120723T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1212 PM PDT MON JUL 23 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

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

* UNTIL 100 PM PDT.

* AT 1207 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
  NORTH CENTRAL SAN BERNARDINO COUNTY...OR 19 MILES WEST OF PRIMM...
  AND WAS MOVING NORTH AT 5 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF NORTHERN SAN BERNARDINO COUNTY INCLUDING 
  KINGSTON AND EXCELSIOR MINE ROAD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3574 11591 3576 11562 3555 11561 3553 11584
TIME...MOT...LOC 1911Z 174DEG 4KT 3562 11574

$$

JH
2 follow-up statements
754 
WWUS55 KVEF 231945
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1245 PM PDT MON JUL 23 2012

CAC071-232000-
/O.CON.KVEF.SV.W.0020.000000T0000Z-120723T2000Z/
SAN BERNARDINO CA-
1245 PM PDT MON JUL 23 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 100 PM PDT 
FOR NORTHEAST SAN BERNARDINO COUNTY...

AT 1241 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 NORTH CENTRAL SAN BERNARDINO COUNTY...OR 20 MILES WEST
OF PRIMM...AND WAS MOVING NORTH AT 5 MPH.

LOCATIONS IMPACTED INCLUDE...
MAINLY RURAL AREAS OF NORTHERN SAN BERNARDINO COUNTY INCLUDING   
KINGSTON AND EXCELSIOR MINE ROAD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3574 11591 3576 11562 3555 11561 3553 11584
TIME...MOT...LOC 1945Z 174DEG 4KT 3566 11574

$$

JH
999 
WWUS55 KVEF 231954
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1254 PM PDT MON JUL 23 2012

CAC071-232003-
/O.EXP.KVEF.SV.W.0020.000000T0000Z-120723T2000Z/
SAN BERNARDINO CA-
1254 PM PDT MON JUL 23 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEAST SAN BERNARDINO 
COUNTY HAS EXPIRED...

THE STORM HAS WEAKENED AND LARGE HAIL AND DAMAGING WINDS ARE NO 
LONGER A THREAT WITH THIS STORM. HEAVY RAIN WILL CONTINUE.

LAT...LON 3574 11591 3576 11562 3555 11561 3553 11584
TIME...MOT...LOC 1953Z 174DEG 4KT 3567 11574

$$

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, 12:18 PM PDTFlash Flood WarningVEFSan Bernardino117 min
Jul 23, 1:54 PM PDTSevere Thunderstorm WarningVEFSan Bernardino66 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; radar from the NEXRAD Level II archive.