Alert archive / California / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 4, NWS San Diego, CA

July 30, 2021Riverside County, California

NWS San Diego, CA issued this severe thunderstorm warning at Jul 30, 2021, 3:17 PM PDT for Riverside County, California. It was in force for 58 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 30, 2021, 3:17 PM PDT (22:17 UTC)
Expired
Jul 30, 2021, 4:15 PM PDT
In force
58 min
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Riverside County, CA

The radar

The San Diego radar (KNKX), 80 km from the middle of the area, began a volume at 22:19 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, 10.3 hours before the alert went out and 98 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 2021-07-30Temperature 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 2021-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 square meters per square second.193958Sfc1 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
2147 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
37 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

076 
WUUS56 KSGX 302217
SVRSGX
CAC065-302315-
/O.NEW.KSGX.SV.W.0004.210730T2217Z-210730T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service San Diego CA
317 PM PDT Fri Jul 30 2021

The National Weather Service in San Diego has issued a

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

* Until 415 PM PDT.

* At 316 PM PDT, a severe thunderstorm was located near Hwy 74
  Between Mountain Center And Anza, or near Anza, moving southeast at
  5 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...
  Southeastern Palm Springs, Idyllwild-Pine Cove, Anza, Hwy 243
  Between Banning And Idyllwild, Hwy 74 Between Hemet And Mountain
  Center, Hwy 74 Between Anza And Palm Desert, Hwy 74 Between
  Mountain Center And Anza, Mountain Center, Cahuilla Indian
  Reservation and Lake Hemet.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3343 11668 3343 11672 3370 11688 3382 11671
      3359 11641
TIME...MOT...LOC 2216Z 324DEG 8KT 3362 11668 

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

JMB
1 follow-up statement
241 
WWUS56 KSGX 302313
SVSSGX

Severe Weather Statement
National Weather Service San Diego CA
413 PM PDT Fri Jul 30 2021

CAC065-302316-
/O.EXP.KSGX.SV.W.0004.000000T0000Z-210730T2315Z/
Riverside CA-
413 PM PDT Fri Jul 30 2021

...THE SEVERE THUNDERSTORM WARNING FOR RIVERSIDE COUNTY WILL EXPIRE
AT 415 PM PDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

LAT...LON 3343 11668 3343 11672 3370 11688 3382 11671
      3359 11641
TIME...MOT...LOC 2306Z 324DEG 8KT 3355 11662 

$$

JMB

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 1:41 PM PDTAreal Flood AdvisorySGXSan Bernardino4 hr
Jul 30, 2:38 PM PDTFlash Flood WarningSGXRiverside, San Diego2 hr
Jul 30, 2:48 PM PDTAreal Flood AdvisorySGXRiverside3 hr
Jul 30, 2:54 PM PDTAreal Flood AdvisorySGXSan Bernardino3 hr
Jul 30, 3:48 PM PDTFlash Flood Warning Considerable damage threatSGXRiverside3 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.