Alert archive / California / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 50, NWS Las Vegas, NV

July 30, 2021San Bernardino County, California; Mohave County, Arizona

NWS Las Vegas, NV issued this severe thunderstorm warning at Jul 30, 2021, 1:14 PM PDT for San Bernardino County, California; Mohave County, Arizona. It was in force for 61 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 30, 2021, 1:14 PM PDT (20:14 UTC)
Expired
Jul 30, 2021, 2:15 PM PDT
In force
61 min
Issued by
NWS Las Vegas, NV
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Mohave County, AZ, San Bernardino County, CA

The radar

The Las Vegas radar (KESX), 153 km from the middle of the area, began a volume at 20:15 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

Phoenix, AZ (KPSR), launched 12:00Z, 8.2 hours before the alert went out and 240 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, Phoenix, AZ at 12:00Z on 2021-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 392 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, Phoenix, AZ at 12:00Z on 2021-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 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
392 J/kg
Mixed-layer CIN
-170 J/kg
Mixed-layer LCL
1882 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
40 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.

638 
WUUS55 KVEF 302014
SVRVEF
AZC015-CAC071-302115-
/O.NEW.KVEF.SV.W.0050.210730T2014Z-210730T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Las Vegas NV
114 PM PDT Fri Jul 30 2021

The National Weather Service in Las Vegas has issued a

* Severe Thunderstorm Warning for...
  Southwestern Mohave County in northwestern Arizona...
  Eastern San Bernardino County in southern California...

* Until 215 PM PDT/215 PM MST/.

* At 114 PM PDT/114 PM MST/, a severe thunderstorm was located near
  Three Dunes Campground, or 8 miles southeast of Lake Havasu City,
  moving northwest at 15 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs and trees.

* Locations impacted include...
  Lake Havasu City, Three Dunes Campground, Cattail Cove State Park,
  Desert Hills and Black Meadow Landing Campground.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3424 11428 3457 11460 3467 11425 3434 11404
TIME...MOT...LOC 2014Z 151DEG 11KT 3440 11424 

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

DSB
2 follow-up statements
911 
WWUS55 KVEF 302051
SVSVEF

Severe Weather Statement
National Weather Service Las Vegas NV
151 PM PDT Fri Jul 30 2021

AZC015-CAC071-302115-
/O.CON.KVEF.SV.W.0050.000000T0000Z-210730T2115Z/
Mohave AZ-San Bernardino CA-
151 PM PDT Fri Jul 30 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM
PDT/215 PM MST/ FOR SOUTHWESTERN MOHAVE AND EASTERN SAN BERNARDINO
COUNTIES...

At 149 PM PDT/149 PM MST/, a severe thunderstorm was located over 
Lake Havasu City, moving northwest at 15 mph.  The storm has now 
collapsed. Severe outflow winds remain possible.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs and trees.

Locations impacted include...
Lake Havasu City, Three Dunes Campground, Cattail Cove State Park,
Desert Hills and Black Meadow Landing Campground.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3424 11428 3457 11460 3467 11425 3434 11404
TIME...MOT...LOC 2049Z 151DEG 11KT 3450 11430 

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

DSB
057 
WWUS55 KVEF 302113
SVSVEF

Severe Weather Statement
National Weather Service Las Vegas NV
213 PM PDT Fri Jul 30 2021

AZC015-CAC071-302122-
/O.EXP.KVEF.SV.W.0050.000000T0000Z-210730T2115Z/
Mohave AZ-San Bernardino CA-
213 PM PDT Fri Jul 30 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN MOHAVE AND
EASTERN SAN BERNARDINO COUNTIES WILL EXPIRE AT 215 PM PDT/215 PM
MST/...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. There is a 
favorable environment for aditional storms to form in the area.

LAT...LON 3424 11428 3457 11460 3467 11425 3434 11404
TIME...MOT...LOC 2112Z 151DEG 11KT 3454 11433 

$$

DSB

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 2:48 PM PDTFlash Flood Warning Considerable damage threatVEFSan Bernardino3 hr
Jul 30, 2:53 PM PDTAreal Flood AdvisoryVEFInyo3 hr
Jul 30, 3:56 PM PDTFlash Flood Warning Considerable damage threatVEFInyo5 hr
Jul 30, 4:07 PM PDTFlash Flood Warning Considerable damage threatVEFSan Bernardino3 hr
Jul 29, 5:12 PM PDTFlash Flood Warning Considerable damage threatVEFMohave2 hr
Jul 29, 6:04 PM PDTSevere Thunderstorm WarningVEFMohave56 min
Jul 30, 12:04 PM PDTAreal Flood AdvisoryVEFMohave3 hr
Jul 30, 12:36 PM PDTFlash Flood Warning Considerable damage threatVEFMohave3 hr
Jul 30, 2:22 PM PDTFlash Flood Warning Considerable damage threatVEFMohave3 hr
Jul 30, 4:17 PM PDTFlash Flood Warning Considerable damage threatVEFMohave3 hr

Nearby

Severe Thunderstorm Warnings in California, 2021Severe Thunderstorm Warnings in Arizona, 2021Every severe thunderstorm warning in 2021

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.