Alert archive / California / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 13, NWS San Diego, CA

August 16, 2018Riverside County, California

NWS San Diego, CA issued this severe thunderstorm warning at Aug 16, 2018, 1:58 PM PDT for Riverside County, California. It was in force for 62 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
Aug 16, 2018, 1:58 PM PDT (20:58 UTC)
Expired
Aug 16, 2018, 3:00 PM PDT
In force
62 min
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Riverside County, CA

The nearest sounding before it

San Diego, CA (KNKX), launched 12:00Z, 9.0 hours before the alert went out and 132 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 2018-08-16Temperature 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 2018-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -17 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
810 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-17 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

287 
WUUS56 KSGX 162058
SVRSGX
CAC065-162200-
/O.NEW.KSGX.SV.W.0013.180816T2058Z-180816T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service San Diego CA
158 PM PDT THU AUG 16 2018

The National Weather Service in San Diego has issued a

* Severe Thunderstorm Warning for...
  Riverside County in southern California...

* Until 300 PM PDT

* At 158 PM PDT, a severe thunderstorm was located over Banning, or
  near Yucaipa, moving northeast at 5 mph.

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

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Yucaipa, western Beaumont, Banning, Calimesa, Cherry Valley and
  Morongo Indian Reservation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3390 11691 3392 11702 3399 11710 3401 11707
      3401 11693 3403 11693 3403 11685
TIME...MOT...LOC 2058Z 224DEG 15KT 3399 11696 

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

JMB
2 follow-up statements
492 
WWUS56 KSGX 162134
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
234 PM PDT THU AUG 16 2018

CAC065-162200-
/O.CON.KSGX.SV.W.0013.000000T0000Z-180816T2200Z/
Riverside CA-
234 PM PDT THU AUG 16 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM PDT
FOR RIVERSIDE COUNTY...

At 233 PM PDT, a severe thunderstorm was located over southwestern
Mount San Gorgonio, moving northeast at 5 mph.

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

SOURCE...Radar indicated. 

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

Heavy rain is also ongoing in the area and a flash flood warning is 
also in effect.

Locations impacted include...
Yucaipa, western Beaumont, Banning, Calimesa, Cherry Valley and
Morongo Indian Reservation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3390 11691 3392 11702 3399 11710 3401 11707
      3401 11693 3403 11693 3403 11685
TIME...MOT...LOC 2133Z 224DEG 15KT 3410 11684 

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

JMB
224 
WWUS56 KSGX 162155
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
255 PM PDT THU AUG 16 2018

CAC065-162204-
/O.EXP.KSGX.SV.W.0013.000000T0000Z-180816T2200Z/
Riverside CA-
255 PM PDT THU AUG 16 2018

...THE SEVERE THUNDERSTORM WARNING FOR RIVERSIDE COUNTY WILL EXPIRE
AT 300 PM PDT...
    
The severe thunderstorm which prompted the warning has weakened in 
the Cherry Valley area. Therefore, the warning will be allowed to 
expire.

LAT...LON 3390 11691 3392 11702 3399 11710 3401 11707
      3401 11693 3403 11693 3403 11685
TIME...MOT...LOC 2154Z 224DEG 15KT 3415 11679 

$$

JMB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 7:25 PM PDTFlash Flood WatchSGXRiverside, San Bernardino, San Diego25 hr
Aug 16, 12:45 PM PDTFlash Flood WarningSGXRiverside3 hr
Aug 16, 1:20 PM PDTAreal Flood AdvisorySGXSan Bernardino3 hr
Aug 16, 1:37 PM PDTFlash Flood WarningSGXSan Bernardino3 hr
Aug 16, 2:30 PM PDTFlash Flood WarningSGXRiverside, San Bernardino77 min
Aug 16, 2:34 PM PDTSevere Thunderstorm WarningSGXRiverside56 min
Aug 16, 3:04 PM PDTFlash Flood WarningSGXSan Bernardino68 min
Aug 16, 3:09 PM PDTSevere Thunderstorm WarningSGXSan Bernardino53 min

Nearby

Severe Thunderstorm Warnings in California, 2018Every severe thunderstorm warning in 2018

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.