Alert archive / California / Severe Thunderstorm Warnings in 2012
Severe Thunderstorm Warning 8, NWS San Diego, CA
NWS San Diego, CA issued this severe thunderstorm warning at Aug 11, 2012, 2:46 PM PDT for Riverside County, California. It was in force for 44 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, 2:46 PM PDT (21:46 UTC)
- Expired
- Aug 11, 2012, 3:30 PM PDT
- In force
- 44 min
- Issued by
- NWS San Diego, CA
- Area
- Storm-based polygon
County Riverside County, CA
The radar
The Santa Ana Mts radar (KSOX), 30 km from the middle of the area, began a volume at 21:45 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, 3:27 PM PDT | HAIL 0.25 | Perris, CA | STRONG THUNDERSTORM WITH LOTS OF IN CLOUD AND CLOUD TO GROUND LIGHTNING. PEA SIZED HAIL AND HEAVY RAINFALL. MINOR STREET FLOODING AND WIND GUSTS 20 TO 25 MPH. RAPID TEMPERATURE DROP FROM 107 TO 79 IN 20 MINUTES. |
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, 9.8 hours before the alert went out and 113 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.
115
WUUS56 KSGX 112146
SVRSGX
CAC065-112230-
/O.NEW.KSGX.SV.W.0008.120811T2146Z-120811T2230Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
246 PM PDT SAT AUG 11 2012
THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
NORTHWESTERN RIVERSIDE COUNTY IN SOUTHERN CALIFORNIA...
THIS INCLUDES THE CITIES OF...RIVERSIDE...MORENO VALLEY...
* UNTIL 330 PM PDT
* AT 240 PM PDT...DOPPLER RADAR CONTINUES TO INDICATE A SEVERE
THUNDERSTORM WAS CAPABLE OF PRODUCING QUARTER SIZE HAIL OVER THE
WARNED AREA. THIS STORM WAS LOCATED 2 MILES NORTH OF PERRIS...OR 7
MILES SOUTHWEST OF MORENO VALLEY...AND MOVING SLOWLY NORTHWEST AT
5 MPH.
* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
WOODCREST...MARCH AFB AND MARCH FIELD
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 3370 11741 3385 11749 3402 11739 3389 11707
3373 11711
TIME...MOT...LOC 2144Z 124DEG 5KT 3383 11713
$$
JT/PG1 follow-up statement
198
WWUS56 KSGX 112218
SVSSGX
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
318 PM PDT SAT AUG 11 2012
CAC065-112230-
/O.CON.KSGX.SV.W.0008.000000T0000Z-120811T2230Z/
RIVERSIDE CA-
318 PM PDT SAT AUG 11 2012
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM PDT
FOR NORTHWESTERN RIVERSIDE COUNTY...
AT 312 PM PDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER
SIZE HAIL WAS LOCATED 6 MILES NORTH NORTHWEST OF LAKE ELSINORE. THIS
STORM IS MOVING SOUTHWEST AT 5 MPH.
OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
WOODCREST...RIVERSIDE...MARCH AFB AND MARCH FIELD
PRECAUTIONARY/PREPAREDNESS ACTIONS...
DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.
IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.
&&
LAT...LON 3370 11741 3385 11749 3402 11739 3389 11707
3373 11711
TIME...MOT...LOC 2216Z 124DEG 5KT 3385 11717
$$
JTThe 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, 3:05 PM PDT | Severe Thunderstorm Warning | SGX | Riverside, San Diego | 40 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.