Alert archive / California / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 2, NWS San Diego, CA

July 22, 2021San Diego County, California

NWS San Diego, CA issued this severe thunderstorm warning at Jul 22, 2021, 4:22 PM PDT for San Diego County, California. It was in force for 53 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 22, 2021, 4:22 PM PDT (23:22 UTC)
Expired
Jul 22, 2021, 5:15 PM PDT
In force
53 min
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County San Diego County, CA

The radar

The San Diego radar (KNKX), 76 km from the middle of the area, began a volume at 23:22 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

San Diego, CA (KNKX), launched 12:00Z, 11.4 hours before the alert went out and 95 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, San Diego, CA at 12:00Z on 2021-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, San Diego, CA at 12:00Z on 2021-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1541 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
-8 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

187 
WUUS56 KSGX 222322
SVRSGX
CAC073-230015-
/O.NEW.KSGX.SV.W.0002.210722T2322Z-210723T0015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service San Diego CA
422 PM PDT Thu Jul 22 2021

The National Weather Service in San Diego has issued a

* Severe Thunderstorm Warning for...
  Northeastern San Diego County in southwestern California...

* Until 515 PM PDT.

* At 422 PM PDT, a severe thunderstorm was located near Hwy S2
  Between Shelter Valley And Agua Caliente, or 7 miles south of Hwy
  78 Between S2 And Borrego Springs Rd, moving north at 35 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Borrego Springs, Hwy 78 Between S2 And Borrego Springs Rd, Hwy 78
  Between Borrego Springs Rd And Ocotillo Wells, Hwy S2 Between
  Shelter Valley And Agua Caliente, Hwy S22 Between Ranchita And
  Borrego Springs, Hwy S2 Between Agua Caliente And Canebrake,
  Borrego Palm Canyon, Hwy S22 Between Borrego Springs And Imperial
  County Line, Fish Creek Wash and Agua Caliente.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large hail and damaging winds and continuous cloud to ground 
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

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

&&

LAT...LON 3294 11626 3296 11647 3343 11645 3343 11616
      3342 11615
TIME...MOT...LOC 2322Z 185DEG 29KT 3303 11636 

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

JMB
2 follow-up statements
271 
WWUS56 KSGX 222355
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
455 PM PDT Thu Jul 22 2021

CAC073-230015-
/O.CON.KSGX.SV.W.0002.000000T0000Z-210723T0015Z/
San Diego CA-
455 PM PDT Thu Jul 22 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM PDT
FOR NORTHEASTERN SAN DIEGO COUNTY...

At 454 PM PDT, a severe thunderstorm was located near Hwy 78 Between
Borrego Springs Rd And Ocotillo Wells, moving northeast at 20 mph.

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

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Borrego Springs, Hwy 78 Between S2 And Borrego Springs Rd, Hwy 78
Between Borrego Springs Rd And Ocotillo Wells, Hwy S2 Between Shelter
Valley And Agua Caliente, Hwy S22 Between Ranchita And Borrego
Springs, Hwy S2 Between Agua Caliente And Canebrake, Borrego Palm
Canyon, Hwy S22 Between Borrego Springs And Imperial County Line,
Fish Creek Wash and Agua Caliente.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 3294 11626 3296 11647 3343 11645 3343 11616
      3342 11615
TIME...MOT...LOC 2354Z 211DEG 29KT 3313 11627 

HAIL...0.75IN
WIND...60MPH
 
$$

JMB
245 
WWUS56 KSGX 230011
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
511 PM PDT Thu Jul 22 2021

CAC073-230021-
/O.EXP.KSGX.SV.W.0002.000000T0000Z-210723T0015Z/
San Diego CA-
511 PM PDT Thu Jul 22 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN SAN DIEGO COUNTY
WILL EXPIRE AT 515 PM PDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

LAT...LON 3294 11626 3296 11647 3343 11645 3343 11616
      3342 11615
TIME...MOT...LOC 0011Z 185DEG 29KT 3327 11626 

$$

JMB

The office that day

Everything else NWS San Diego, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 22, 3:45 PM PDTFlash Flood Warning Considerable damage threatSGXSan Diego2 hr
Jul 22, 4:18 PM PDTFlash Flood Warning Considerable damage threatSGXSan Diego117 min
Jul 22, 4:23 PM PDTFlash Flood Warning Considerable damage threatSGXRiverside2 hr

Nearby

Severe Thunderstorm Warnings in California, 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.