Alert archive / California / Severe Thunderstorm Warnings in 2012
Severe Thunderstorm Warning 9, NWS San Diego, CA
NWS San Diego, CA issued this severe thunderstorm warning at Aug 11, 2012, 3:05 PM PDT for Riverside County, San Diego County, California. It was in force for 40 min. 1 report 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
- Aug 11, 2012, 3:05 PM PDT (22:05 UTC)
- Expired
- Aug 11, 2012, 3:45 PM PDT
- In force
- 40 min
- Issued by
- NWS San Diego, CA
- Area
- Storm-based polygon
Counties Riverside County, CA, San Diego County, CA
The radar
The San Diego radar (KNKX), 64 km from the middle of the area, began a volume at 22:08 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 11, 3:30 PM PDT | TSTM WND DMG | Temecula, CA | NORTHEAST TEMECULA. WIND ESTIMATES 60-65 MPH. A MICROBURST CAUSED DAMAGE IN A RESIDENTIAL NEIGHBORHOOD. THE MICROBURST DESCENDED FROM THE THUNDERSTORM DOWNWARD INTO THE MIDDLE OF A BACKYARD AND WAS ABOUT 20 YARDS WIDE BLOWING DOWN THE FENCES ON THE NORTH AND S |
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, 10.1 hours before the alert went out and 79 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.
- Mixed-layer CAPE
- 268 J/kg
- Mixed-layer CIN
- -713 J/kg
- Mixed-layer LCL
- 1560 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- 21 m²/s²
- 0-3 km storm-relative helicity
- 30 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
511 WUUS56 KSGX 112205 SVRSGX CAC065-073-112245- /O.NEW.KSGX.SV.W.0009.120811T2205Z-120811T2245Z/ BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SAN DIEGO CA 305 PM PDT SAT AUG 11 2012 THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHWESTERN RIVERSIDE COUNTY IN SOUTHERN CALIFORNIA... THIS INCLUDES THE CITY OF TEMECULA... NORTH CENTRAL SAN DIEGO COUNTY IN SOUTHWEST CALIFORNIA... * UNTIL 345 PM PDT * AT 300 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS STORM WAS LOCATED 9 MILES SOUTHEAST OF TEMECULA...AND MOVING SOUTHWEST AT 5 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... RURAL NORTHERN SAN DIEGO COUNTY AT 320 PM PDT PRECAUTIONARY/PREPAREDNESS ACTIONS... DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM. WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM. IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING. && LAT...LON 3352 11720 3365 11698 3345 11683 3334 11701 TIME...MOT...LOC 2204Z 040DEG 12KT 3343 11701 $$ JT
1 follow-up statement
522 WWUS56 KSGX 112243 SVSSGX SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE SAN DIEGO CA 343 PM PDT SAT AUG 11 2012 CAC065-073-112247- /O.EXP.KSGX.SV.W.0009.000000T0000Z-120811T2245Z/ SAN DIEGO CA-RIVERSIDE CA- 343 PM PDT SAT AUG 11 2012 ...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN RIVERSIDE AND NORTH CENTRAL SAN DIEGO COUNTIES WILL EXPIRE AT 345 PM PDT... THE THUNDERSTORM THAT HAD PROMPTED THE SEVERE THUNDERSTORM WARNING HAS WEAKENED...THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE. HOWEVER...PEA SIZE HAIL...GUSTY WINDS...AND CLOUD TO GROUND LIGHTNING ARE STILL POSSIBLE. LAT...LON 3352 11720 3365 11698 3345 11683 3334 11701 TIME...MOT...LOC 2237Z 040DEG 12KT 3335 11709 $$ JT
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 10, 5:20 PM PDT | Areal Flood Advisory | SGX | Riverside | 115 min |
| Aug 11, 12:00 PM PDT | Areal Flood Advisory | SGX | San Bernardino | 92 min |
| Aug 11, 12:58 PM PDT | Areal Flood Advisory | SGX | San Bernardino | 2 hr |
| Aug 11, 1:23 PM PDT | Flash Flood Warning | SGX | San Bernardino | 3 hr |
| Aug 11, 1:58 PM PDT | Areal Flood Advisory | SGX | Riverside, San Bernardino | 3 hr |
| Aug 11, 2:03 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 27 min |
| Aug 11, 2:23 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 22 min |
| Aug 11, 2:46 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 44 min |
| Aug 11, 3:22 PM PDT | Areal Flood Advisory | SGX | San Bernardino | 113 min |
| Aug 11, 3:33 PM PDT | Severe Thunderstorm Warning | SGX | Orange, Riverside | 42 min |
| Aug 11, 4:40 PM PDT | Areal Flood Advisory | SGX | San Diego | 3 hr |
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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.