Alert archive / California / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 49, NWS Las Vegas, NV

August 9, 2018San Bernardino County, California

NWS Las Vegas, NV issued this severe thunderstorm warning at Aug 9, 2018, 10:03 PM PDT for San Bernardino County, California. It was in force for 27 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: Aug 9, 2018, 10:03 PM PDT (05:03 UTC)
Expired: Aug 9, 2018, 10:30 PM PDT
In force: 27 min
Issued by: NWS Las Vegas, NV
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County San Bernardino County, CA

The radar

The Las Vegas radar (KESX), 159 km from the middle of the area, began a volume at 05:02 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 00:00Z, 5.1 hours before the alert went out and 245 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: 2458 J/kg
Mixed-layer CIN: -3 J/kg
Mixed-layer LCL: 3026 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 16 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted.

490 
WUUS55 KVEF 100503
SVRVEF
CAC071-100530-
/O.NEW.KVEF.SV.W.0049.180810T0503Z-180810T0530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Las Vegas NV
1003 PM PDT THU AUG 9 2018

The National Weather Service in Las Vegas has issued a

* Severe Thunderstorm Warning for...
  Southeastern San Bernardino County in southern California...

* Until 1030 PM PDT.

* At 1003 PM PDT, a severe thunderstorm was located 8 miles north of
  Vidal Junction, or 9 miles southeast of Highway 95 At Mile Marker
  29, moving southwest at 20 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs and trees.

* Locations impacted include...
  Highway 95 At Mile Marker 29 and Vidal Junction. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3442 11492 3447 11451 3423 11436 3408 11464
      3408 11479
TIME...MOT...LOC 0503Z 064DEG 18KT 3431 11458 

HAIL...<.75IN
WIND...60MPH
 
$$

Wolf

3 follow-up statements

867 
WWUS55 KVEF 100512
SVSVEF

Severe Weather Statement
National Weather Service Las Vegas NV
1012 PM PDT THU AUG 9 2018

CAC071-100530-
/O.CON.KVEF.SV.W.0049.000000T0000Z-180810T0530Z/
San Bernardino CA-
1012 PM PDT THU AUG 9 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1030 PM PDT
FOR SOUTHEASTERN SAN BERNARDINO COUNTY...

At 1011 PM PDT, a severe thunderstorm was located 8 miles north of
Vidal Junction, or 10 miles south of Highway 95 At Mile Marker 29,
and is nearly stationary.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs and trees.

Locations impacted include...
Highway 95 At Mile Marker 29 and Vidal Junction. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3442 11492 3447 11451 3423 11436 3408 11464
      3408 11479
TIME...MOT...LOC 0511Z 064DEG 18KT 3429 11462 

HAIL...1.00IN
WIND...60MPH
 
$$

Wolf

746 
WWUS55 KVEF 100523
SVSVEF

Severe Weather Statement
National Weather Service Las Vegas NV
1023 PM PDT THU AUG 9 2018

CAC071-100530-
/O.CON.KVEF.SV.W.0049.000000T0000Z-180810T0530Z/
San Bernardino CA-
1023 PM PDT THU AUG 9 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1030 PM PDT
FOR SOUTHEASTERN SAN BERNARDINO COUNTY...

At 1022 PM PDT, a severe thunderstorm was located 8 miles northwest
of Vidal Junction, or 11 miles south of Highway 95 At Mile Marker 29,
and is nearly stationary.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs and trees.

Locations impacted include...
Highway 95 At Mile Marker 29 and Vidal Junction. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3442 11492 3447 11451 3423 11436 3408 11464
      3408 11479
TIME...MOT...LOC 0522Z 064DEG 18KT 3427 11468 

HAIL...1.00IN
WIND...60MPH
 
$$

Wolf

263 
WWUS55 KVEF 100529
SVSVEF

Severe Weather Statement
National Weather Service Las Vegas NV
1029 PM PDT THU AUG 9 2018

CAC071-100537-
/O.EXP.KVEF.SV.W.0049.000000T0000Z-180810T0530Z/
San Bernardino CA-
1029 PM PDT THU AUG 9 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SAN BERNARDINO
COUNTY WILL EXPIRE AT 1030 PM PDT...
    
The severe thunderstorm will be allowed to expire, however a new 
severe thunderstorm warning has been issued in its place. Listen to 
local alerts for hazardous weather conditions, including 
damaging winds and heavy rain. 

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Las Vegas.

LAT...LON 3442 11492 3447 11451 3423 11436 3408 11464
      3408 11479
TIME...MOT...LOC 0527Z 064DEG 18KT 3426 11469 

$$

Wolf

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 7:57 PM PDT	Dust Storm Warning	VEF	San Bernardino	93 min
Aug 9, 10:26 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	39 min
Aug 9, 10:31 PM PDT	Areal Flood Advisory	VEF	San Bernardino	3 hr

Nearby

Severe Thunderstorm Warnings in California, 2018 Every severe thunderstorm warning in 2018

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.