Alert archive / California / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 15, NWS San Diego, CA

September 24, 2021San Diego County, California

NWS San Diego, CA issued this severe thunderstorm warning at Sep 24, 2021, 3:20 PM PDT for San Diego County, California. It was in force for 55 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Sep 24, 2021, 3:20 PM PDT (22:20 UTC)
Expired
Sep 24, 2021, 4:15 PM PDT
In force
55 min
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County San Diego County, CA

The radar

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

What was reported inside it

TimeReportWhereRemark
Sep 24, 3:30 PM PDTTSTM WND DMG1 Se La Mesa, CANBC AND CBS REPORTED LARGE 70 FOOT PINE TREE THAT WAS DOWNED ON A HOME AND DAMAGED A GARAGE AS WELL AS DOWNED A POWER LINE. SMALLER TREE DOWN IN THE SAME AREA. 4500 PANORAMA DRIVE.
Sep 24, 3:50 PM PDTHAIL 0.253 Nne San Diego, CA2 MPING REPORTS OF PEA SIZED HAIL.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

San Diego, CA (KNKX), launched 12:00Z, 10.3 hours before the alert went out and 10 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 2021-09-24Temperature 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 2021-09-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -36 square meters per square second.1939587897Sfc1 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
1990 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-36 m²/s²
0-3 km storm-relative helicity
15 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

735 
WUUS56 KSGX 242220
SVRSGX
CAC073-242315-
/O.NEW.KSGX.SV.W.0015.210924T2220Z-210924T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service San Diego CA
320 PM PDT Fri Sep 24 2021

The National Weather Service in San Diego has issued a

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

* Until 415 PM PDT.

* At 319 PM PDT, a severe thunderstorm was located over Lakeside, or
  near El Cajon, moving west at about 15 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Chula Vista, Oceanside, Carlsbad, El Cajon, Vista, Encinitas,
  National City, La Mesa, Poway and Imperial Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3261 11714 3260 11710 3266 11713 3269 11714
      3262 11713 3264 11714 3269 11720 3271 11720
      3268 11716 3269 11715 3273 11721 3297 11726
      3316 11735 3319 11696 3257 11682 3256 11713
TIME...MOT...LOC 2219Z 239DEG 49KT 3287 11688 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Small
2 follow-up statements
386 
WWUS56 KSGX 242245
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
345 PM PDT Fri Sep 24 2021

CAC073-242315-
/O.CON.KSGX.SV.W.0015.000000T0000Z-210924T2315Z/
San Diego CA-
345 PM PDT Fri Sep 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM PDT
FOR SOUTHWESTERN SAN DIEGO COUNTY...

At 339 PM PDT, a severe thunderstorm was located near downtown San 
Diego, moving west at about 15 mph. So far heavy rainfall and 
localized flooding has been reported. 

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Chula Vista, Oceanside, Carlsbad, El Cajon, Vista, Encinitas,
National City, La Mesa, Poway and Imperial Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3261 11714 3260 11710 3266 11713 3269 11714
      3262 11713 3264 11714 3269 11720 3271 11720
      3268 11716 3269 11715 3273 11721 3297 11726
      3316 11735 3319 11696 3257 11682 3256 11713
TIME...MOT...LOC 2239Z 239DEG 49KT 3301 11659 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Small
419 
WWUS56 KSGX 242312
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
412 PM PDT Fri Sep 24 2021

CAC073-242320-
/O.EXP.KSGX.SV.W.0015.000000T0000Z-210924T2315Z/
San Diego CA-
412 PM PDT Fri Sep 24 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN SAN DIEGO COUNTY
WILL EXPIRE AT 415 PM PDT...
    
The severe thunderstorm which prompted the warning has weakened
and moved out of the warned area. Therefore, the warning will be
allowed to expire.

LAT...LON 3261 11714 3260 11710 3266 11713 3269 11714
      3262 11713 3264 11714 3269 11720 3271 11720
      3268 11716 3269 11715 3273 11721 3297 11726
      3316 11735 3319 11696 3257 11682 3256 11713
TIME...MOT...LOC 2310Z 239DEG 49KT 3316 11630 

$$

Small

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 24, 8:56 AM PDTFlash Flood WatchSGXRiverside, San Diego10 hr
Sep 24, 11:08 AM PDTBeach Hazards StatementSGXOrange, San Diego8 hr
Sep 24, 12:13 PM PDTSevere Thunderstorm WarningSGXSan Diego31 min
Sep 24, 12:21 PM PDTFlash Flood Warning Considerable damage threatSGXSan Diego56 min
Sep 24, 1:24 PM PDTSevere Thunderstorm WarningSGXSan Diego51 min
Sep 24, 1:28 PM PDTFlash Flood Warning Considerable damage threatSGXSan Diego2 hr
Sep 24, 2:09 PM PDTFlash Flood Warning Considerable damage threatSGXSan Diego3 hr
Sep 24, 2:41 PM PDTSevere Thunderstorm WarningSGXSan Diego64 min
Sep 24, 2:59 PM PDTSpecial Weather StatementSGXSan Diego61 min
Sep 24, 3:14 PM PDTSpecial Marine WarningSGX91 min
Sep 24, 3:47 PM PDTSpecial Weather StatementSGXOrange58 min
Sep 24, 3:56 PM PDTSpecial Marine WarningSGX94 min
Sep 24, 4:40 PM PDTSpecial Marine WarningSGX65 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.