Alert archive / California / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 19, NWS San Diego, CA

September 7, 2024Riverside County, San Diego County, California

NWS San Diego, CA issued this severe thunderstorm warning at Sep 7, 2024, 1:51 PM PDT for Riverside County, San Diego County, California. It was in force for 54 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 7, 2024, 1:51 PM PDT (20:51 UTC)
Expired: Sep 7, 2024, 2:45 PM PDT
In force: 54 min
Issued by: NWS San Diego, CA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Riverside County, CA, San Diego County, CA

The radar

The San Diego radar (KNKX), 80 km from the middle of the area, began a volume at 20:54 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, 8.9 hours before the alert went out and 100 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 110 J/kg
Mixed-layer CIN: -793 J/kg
Mixed-layer LCL: 2834 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 29 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS San Diego, CA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 7, 9:23 AM PDT, 4 hours 28 minutes earlier.

Area forecast discussion, Sep 7, 9:23 AM PDT, 4 hours 28 minutes before

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In the hours before

Special weather statement, Sep 7, 1:02 PM PDT, 49 minutes before

Special Weather Statement
National Weather Service San Diego CA
102 PM PDT Sat Sep 7 2024

CAZ048-056-072045-
Riverside County Mountains CA-
San Bernardino and Riverside County Valleys-The Inland Empire CA-
102 PM PDT Sat Sep 7 2024

...A STRONG THUNDERSTORM WILL IMPACT RIVERSIDE COUNTY THROUGH 145 PM
PDT...

At 102 PM PDT, Doppler radar was tracking a strong thunderstorm over
Hwy 74 Between Hemet And Mountain Center, or near Idyllwild-Pine
Cove, moving northeast at 5 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Idyllwild-Pine Cove, Hwy 243 Between Banning And Idyllwild, Mt San
Jacinto State Park, Hwy 74 Between Hemet And Mountain Center,
Mountain Center, Valle Vista, Saboba Indian Reservation, and Sage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3362 11678 3366 11694 3373 11688 3389 11685
      3376 11660
TIME...MOT...LOC 2002Z 206DEG 6KT 3373 11680

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Zuber

Special weather statement, Sep 7, 1:31 PM PDT, 20 minutes before

Special Weather Statement
National Weather Service San Diego CA
131 PM PDT Sat Sep 7 2024

CAZ048-056-058-072115-
San Diego County Mountains CA-Riverside County Mountains CA-
San Bernardino and Riverside County Valleys-The Inland Empire CA-
131 PM PDT Sat Sep 7 2024

...A STRONG THUNDERSTORM WILL IMPACT RIVERSIDE AND NORTH CENTRAL SAN
DIEGO COUNTIES THROUGH 215 PM PDT...

At 131 PM PDT, Doppler radar was tracking a strong thunderstorm over
Aguanga, or 14 miles southwest of Anza. This thunderstorm was nearly
stationary.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Aguanga, Palomar Mountain State Park, Hwy 79 Between Oak Grove And
Aguanga, Palomar Mountain, Hwy 79 Between Warner Springs And Oak
Grove, and Oak Grove.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3344 11697 3352 11681 3342 11672 3332 11690
TIME...MOT...LOC 2031Z 314DEG 1KT 3342 11687

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Zuber

Special weather statement, Sep 7, 1:45 PM PDT, 6 minutes before

Special Weather Statement
National Weather Service San Diego CA
145 PM PDT Sat Sep 7 2024

CAZ048-056-061-072130-
Riverside County Mountains CA-Coachella Valley CA-
San Bernardino and Riverside County Valleys-The Inland Empire CA-
145 PM PDT Sat Sep 7 2024

...A STRONG THUNDERSTORM WILL IMPACT RIVERSIDE COUNTY THROUGH 230 PM
PDT...

At 145 PM PDT, Doppler radar was tracking a strong thunderstorm near
Hwy 74 Between Hemet And Mountain Center, or 7 miles southwest of
Idyllwild-Pine Cove, moving northeast at 20 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Idyllwild-Pine Cove, Mt San Jacinto State Park, Hwy 243 Between
Banning And Idyllwild, Hwy 74 Between Hemet And Mountain Center,
Valle Vista, East Hemet, Hwy 74 Between Mountain Center And Anza,
Mountain Center, Aguanga, Lake Hemet, Sage, and Saboba Indian
Reservation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3358 11687 3373 11697 3385 11668 3377 11656
      3363 11661
TIME...MOT...LOC 2045Z 236DEG 16KT 3370 11684

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Zuber

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 1:02 PM PDT	Special Weather Statement	SGX		43 min
Sep 7, 1:31 PM PDT	Special Weather Statement	SGX	San Diego	44 min
Sep 7, 1:43 PM PDT	Areal Flood Advisory	SGX	Riverside	2 hr
Sep 7, 1:45 PM PDT	Special Weather Statement	SGX		45 min
Sep 7, 2:10 PM PDT	Areal Flood Advisory	SGX	Riverside, San Diego	2 hr
Sep 7, 2:17 PM PDT	Special Weather Statement	SGX		43 min
Sep 7, 2:20 PM PDT	Special Weather Statement	SGX	San Diego	40 min
Sep 7, 2:27 PM PDT	Areal Flood Advisory	SGX	San Diego	2 hr
Sep 7, 2:32 PM PDT	Areal Flood Advisory	SGX	San Diego	2 hr
Sep 7, 2:34 PM PDT	Severe Thunderstorm Warning	SGX	San Diego	56 min
Sep 7, 2:36 PM PDT	Severe Thunderstorm Warning	SGX	San Diego	19 min
Sep 7, 2:50 PM PDT	Special Weather Statement	SGX		40 min
Sep 7, 3:10 PM PDT	Severe Thunderstorm Warning	SGX	San Diego	32 min
Sep 7, 3:15 PM PDT	Areal Flood Advisory	SGX	San Diego	2 hr
Sep 7, 3:24 PM PDT	Special Weather Statement	SGX		51 min
Sep 7, 3:35 PM PDT	Special Weather Statement	SGX		40 min
Sep 7, 3:39 PM PDT	Areal Flood Advisory	SGX	Riverside, San Bernardino	2 hr
Sep 7, 3:40 PM PDT	Severe Thunderstorm Warning	SGX	Riverside	35 min
Sep 7, 3:57 PM PDT	Areal Flood Advisory	SGX	Riverside	2 hr

Nearby

Severe Thunderstorm Warnings in California, 2024 Every severe thunderstorm warning in 2024

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.