Alert archive / California / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 13, NWS Los Angeles, CA

August 6, 1990Riverside County, California

NWS Los Angeles, CA issued this severe thunderstorm warning at Aug 6, 1990, 8:00 PM PDT for Riverside County, California. It was in force for 55 min.

The area

The counties it named.

The facts

Issued
Aug 6, 1990, 8:00 PM PDT (03:00 UTC)
Expired
Aug 6, 1990, 8:55 PM PDT
In force
55 min
Issued by
NWS Los Angeles, CA
Area
Whole counties

County Riverside County, CA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

San Diego, CA (KNKX), launched 00:00Z, 3.0 hours before the alert went out and 154 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 00:00Z on 1990-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 00:00Z on 1990-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 49 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
1 J/kg
Mixed-layer CIN
-838 J/kg
Mixed-layer LCL
1663 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
124 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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.

In the hours before

Special weather statement, Aug 6, 2:19 PM PDT, 5 hours 41 minutes before
CAZALL-070000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LOS ANGELES CA
220 PM PDT MON AUG 6 1990

...HEAVY THUNDERSTORM NEAR REDLANDS...

AS OF 215 PM RADAR AND SATELLITE INDICATED THUNDERSTORMS CONTINUING
TO DEVELOP OVER ALL OF SOUTHERN CALIFORNIA. A HEAVY THUNDERSTORM WAS
LOCATED NEAR REDLANDS...AND WAS MOVING TOWARDS THE WEST. THIS STORM
WILL LIKELY PRODUCE BRIEF HEAVY RAIN...STRONG GUSTY WINDS AND FREQUENT
LIGHTNING AS IT MOVES THROUGH THE AREA.

CONDITIONS ARE FAVORABLE FOR STORMS TO CONTINUE TO FORM OVER THE
MOUNTAIN AND DESERT AREAS THROUGH THIS AFTERNOON AND EVENING...WITH
SOME OF THESE MOVING OVER THE COASTAL AND VALLEY AREAS.

THESE STORMS MAY PRODUCE STRONG WINDS...FREQUENT LIGHTNING AND BRIEF
HEAVY RAIN. WINDS GUSTING TO 50 MPH ARE POSSIBLE IN DESERT AREAS...
WITH REDUCED VISIBILITIES IN BLOWING DUST AND SAND.

PERSONS ARE URGED TO USE CAUTION AND OBSERVE THE RULES OF SAFETY
CONCERNING THUNDERSTORMS. IF YOU ARE OUTSIDE AND A THUNDERSTORM
APPROACHES...SEEK SHELTER INDOORS.

PETERSON
Special weather statement, Aug 6, 6:02 PM PDT, 1 hour 58 minutes before
CA003-004-011-015-070415-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SANTA MARIA CA
600 PM PDT MON AUG 06 1990

...THUNDERSTORMS IN THE SOUTHERN MOUNTAINS OF SAN LUIS OBISPO COUNTY
AND EASTERN SANTA BARBARA COUNTY...

AN AREA OF THUNDERSTORMS DEVELOPED OVER THE MOUNTAINS OF THE
THE CENTRAL COAST.  REPORTS INDICATED LIGHNING AND RAINSHOWERS WITH
GUSTY WINDS IN THE LOS PADRES NATIONAL FOREST NEAR CUYAMA AND
SCATTERED THUNDERSTORM ACTIVITY IN THE SANTA YNEZ AND SIERRA MADRE
MOUNTAINS IN SANTA BARABRA COUNTY.  A SPOTTER IN SANTA MARIA AREA
REPORTED HEARING THUNDER AT 515 PM.

NOT MUCH RAINFALL IS EXPECTED FROM THESE STORMS BUT DANGEROUS
LIGHTNING AND STRONG GUSTY WINDS CAN BE EXPECTED OVER THE NEXT FEW
HOURS UNTIL THEY BEGIN TO DIMINISH LATER TONIGHT.

IF YOU ARE TRAVELLING TO OR IN THE FOOTHILLS AND MOUNTAINS WATCH FOR
LIGHTNING AND STRONG GUSTY WINDS IF THUNDERSTORMS APPROACH.

FURTHER STATEMENTS WILL BE ISSUED AS NECESSARY.

DR

The office that day

Everything else NWS Los Angeles, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 6, 5:50 PM PDTSevere Thunderstorm WarningLOXSan Bernardino2 hr
Aug 6, 8:00 PM PDTSevere Thunderstorm WarningLOXSan Bernardino55 min

Nearby

Severe Thunderstorm Warnings in California, 1990Every severe thunderstorm warning in 1990

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.