Alert archive / California / Flash Flood Warnings in 1989

Flash Flood Warning 2, NWS Los Angeles, CA

August 9, 1989Riverside County, California

NWS Los Angeles, CA issued this flash flood warning at Aug 9, 1989, 4:00 PM PDT for Riverside County, California. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Aug 9, 1989, 4:00 PM PDT (23:00 UTC)
Expired
Aug 9, 1989, 7:00 PM PDT
In force
3 hr
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 12:00Z, 11.0 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 12:00Z on 1989-08-09Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 12:00Z on 1989-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 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
3639 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KLAX 092318
FFWLAX
CAC025-065-100200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LOS ANGELES CA
4 PM PDT WED AUG 9 1989

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM AND
FLASH FLOOD WARNING EFFECTIVE UNTIL 7 PM PDT FOR PEOPLE IN THE
FOLLOWING COUNTIES OF:

EXTREME SOUTHEASTERN RIVERSIDE
EXTREME NORTHEASTERN IMPERIAL

AT 4 PM RADAR INDICATED A STRONG THUNDERSTORM WAS CROSSING THE
ARIZONA BORDER NEAR PALO VERDE AND WAS MOVING INTO CALIFORNIA. THE
WARNING INCLUDES AREAS FROM DESERT CENTER TO BLYTHE SOUTH TO THE
PALO VERDE MOUNTAINS.

THE STORM IS MOVING TOWARDS THE NORTHWEST AT 15 MPH.

THIS STORM IS EXPECTED TO BRING STRONG WINDS GUSTING TO 60 MPH OR MORE
AND HEAVY RAIN...FOR THE NEXT FEW HOURS. THIS HEAVY RAIN WILL LIKELY
CAUSE LOCAL FLASH FLOODING IN THE WARNING AREA.

IF YOU ARE DRIVING IN THE WARNING AREA USE EXTRA CAUTION...AVOID
FLOODED HIGHWAY DIPS...AND BE 7AWARE THAT THE STRONG WINDS MAY REDUCE
VISIBILITIES TO NEAR ZERO.

IF YOU ARE OUTSIDE AND THREATENING WEATHER APPROACHES GO TO A SAFE PLACE
IMMEDIATELY.

PETERSON

What forecasters said that day

The local office's own words before this flash flood 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 9, 11:41 AM PDT, 4 hours 19 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LOS ANGELES CA
1140 AM PDT WED AUG 9 1989

...THUNDERSTORMS DEVELOPING IN SOUTHERN CA MOUNTAINS AND DESERTS...

A SOUTHERLY FLOW ALOFT OF MOIST UNSTABLE AIR CONTINUES OVER THE
SOUTHLAND TODAY...AND WIDELY SCATTERED THUNDERSTORMS ARE BEGINNING
TO DEVELOP IN THE MOUNTAINS AND INTERIOR.

TODAYS THUNDERSTORM ACTIVITY WILL BE ACCOMPANIED BY DEADLY LIGHTNING...
BRIEF HEAVY RAIN...AND GUSTY WINDS.  MINOR FLOODING OF ROADWAYS MAY
ACCOMPANY THE BRIEF HEAVY RAIN...DO NOT ATTEMPT TO CROSS FLOODED
ROADWAYS.  IN ADDITION...LOCAL STRONG GUSTY WINDS MAY PRODUCE BLOWING
DUST TAT MAY BRIEFLY REDUCE VISIBILTIES.

IF YOU ARE IN THE MOUNTAIN OR INTERIOR SECTIONS...KEEP ADVISED OF THE
LATEST ADVISED OF THE LATEST WEATHER INFORMATION.  IT IS POSSIBLE
THAT LOCALIZED FLASH FLOODING WILL DEVELOP ASSOCIATED WITH THE HEAVIER
THUNDERSTORMS THIS AFTERNOON AND EVENING.  STAY CLEAR OF DESERT DRY
WASHES...OR BE P|REPARED TO MOVE TO HIGHER GROUND IF YOU SEE
THUNDERSTORM ACTIVITY NEARBY.

FURTHER STATEMENTS WILL BE ISSUED AS CONDITIONS WARRANT.

HAMILTON
Local storm report, Aug 9, 1:56 PM PDT, 2 hours 4 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES, CA
1255 PM PST WED AUG 09 1989

 FOLLOWING INFORMATION IS FROM THE SERIES OF THUNDERSTORMS IN
SOUTHERN CALIFORNIA ON AUGUST 8 1989.

THUNDERSTORMS FORMED ALONG THE EAST SIDE OF MANY OF THE MOUNTAIN
RANGES DURING THE AFTERNOON. THE MORE SIGNIFICANT ONES PRODUCED HEAVY
SHOWERS OVER THE HIGHER REACHES OF THE MOUNTAINS WITH LIGHTER AMOUNTS
IN THE VALLEY AREAS.

509PM PDT...INYO COUNTY...10S OF LONE PINE. HEAVY RAINS IN THE MOUNTAINS
            CAUSED MUD TO COVER ALL 4 LANES OF U.S. 395 APPROXIMATELY
            1-1 1/2 FT DEEP. ROAD CLOSED FROM 515PM TO 430AM WED.

706PM PDT...INYO COUNTY...OLANCHA. APPROXIMATELY 1 MILE NORTH AND SOUTH
            OF HIGHWAYS 395/190 JUNCTION. FLOW FROM MOUNTAIN THUNDER/
            STORMS WASHED CONSIDERABLE DEBRIS INTO AQUEDUCT COMPLETELY
            DAMMING IT. WATER AND MUD WAS OVER HIGHWAY JUNCTION AREA.
            1 MILE OF AQUEDUCT COMPLETELY FILLED WITH DEBRIS AND MORE
            THAN 1 MILE WITH VARIOUS AMOUNTS OF DEBRIS. 10-14 DAYS
            ESTIMATED TO CLEAR.

SOME DEBRIS OVER HIGHWAY 168 NEAR DEEP SPRINGS AREA ESE OF BISHOP DUE
TO HEAVY RAINS. LOCAL FLOODING OCCURRED IN THE SHERWOOD CREEK AREA
SW OF BISHOP IN THE LATE AFTERNOON AND EVENING.

IN MONO COUNTY...LOCAL FLOODING 10-15 W OF LEE VINING WHERE HEAVY RAIN
REPORTED FOR 1-2 HOURS. ROCK AND DEBRIS SLIDES NEAR TIOGA PASS WITH
A CAR OFF THE ROAD DURING MORNING OF AUG 8 DUE TO RAINS.

RAINFALL REPORTS...
OAK CREEK        .40            CAINE RANCH               .61
ROUND VALLEY     .10            TINAMAHA...S OF BIG PINE. .08
BENTON           .13            LONE PINE           OVER 1.00
ROCK CREEK       .10            INDEPENDENCE              .18
WILD ROSE        .08            HAIWEE                    .08
STOVEPIPE WELLS  .20            BISHOP                     T
BIG PINE         .21            MAMMOTH LAKES       OVER 1.00
LONG VALLEY      .39

M_CDUFFIE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 4:00 PM PDTSevere Thunderstorm WarningLOXRiverside3 hr

Nearby

Flash Flood Warnings in California, 1989Every flash flood warning in 1989

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.