Alert archive / California / Flash Flood Warnings in 1996

Flash Flood Warning 2, NWS Los Angeles, CA

July 28, 1996Riverside County, California

NWS Los Angeles, CA issued this flash flood warning at Jul 28, 1996, 3:35 PM PDT for Riverside County, California. It was in force for 115 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
Jul 28, 1996, 3:35 PM PDT (22:35 UTC)
Expired
Jul 28, 1996, 5:30 PM PDT
In force
115 min
Issued by
NWS Los Angeles, CA
Area
Whole counties

County Riverside County, CA

The radar

The San Diego radar (KNKX), 134 km from the middle of the area, began a volume at 22:36 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, 10.6 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 1996-07-28Temperature 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 1996-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
1719 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
32 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 282238
FFWLAX
CAC065-071-290030-
 
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE OXNARD CA
335 PM PDT SUN JUL 28 1996
 
THE NATIONAL WEATHER SERVICE IN OXNARD HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  530 PM PDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHERN CALIFORNIA
 
   ...NORTHWESTERN RIVERSIDE COUNTY
   ...SOUTHWESTERN SAN BERNARDINO COUNTY
 
...SPECIFICALLY THE FLASH FLOOD WARNING COVERS THE MORONGO INDIAN
RESERVATION AND VICINITY...NORTH OF INTERSTATE 10. AT 330 PM A LARGE...
THUNDERSTORM WAS NEARLY STATIONARY OVER THE SAN BERNADINO MOUNTAINS NEAR
THE MORONGO INDIAN RESERVATION. RADAR INDICATES HEAVY RAIN IS OCCURRING
...WITH ESTIMATED RAINFALL RATES OVER 1.5 INCH PER HOUR...WHICH WILL LIK
 CAUSE FLASH FLOODING OF CREEKS AND CANYONS IN THE AREA.
 
 A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT.  MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES.  DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT.  TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.
 
 
DANIELSON

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, Jul 28, 1:19 PM PDT, 2 hours 16 minutes before
CAZ013-018-019-280000-

SPECIAL WATHER STATEMENT
NATIONAL WEATHER SERVICE OXNARD CA
115 PM PDT SUN JUL 28 1996

...SHOWERS AND THUNDERSTORMS ARE EXPECTED IN THE MOUNTAINS OF SOUTHERN
CALIFORNIA THIS AFTERNOON AND EVENING...

AT 112 PM PDT...RADAR AND SATELLITE DATA INDICATED THAT WIDESPREAD
SHOWER AND THUNDERSTORM ACTIVITY WAS BREAKING OUT OVER THE MOUNTAINS OF
SOUTHERN CALIFORNIA. THE HEAVIEST OF THESE SHOWERS WERE LOCATED OVER
THE SAN BERNARDINO MOUNTAINS...THE SAN JACINTO MOUNTAINS...AND OVER THE
MOUNTAINS OF SAN DIEGO NEAR THE MEXICAN BORDER. A THUNDERSTORM WAS ALSO
LOCATED OVER THE MOJAVE DESERT JUST NORTH OF WRIGHTWOOD. WHILE
THUNDERSTORMS WILL TEND TO DEVELOP FIRST OVER THE MOUNTAINS...UPPER
LEVEL WINDS WILL TEND TO BLOW THESE STORMS AWAY FROM COASTAL VALLEYS
AND INTO ADJACENT DESERT AREAS.

AT 100 PM...A SPOTTER NEAR BIG BEAR IN THE SAN BERNARDINO MOUNTAINS
REPORTED HEAVY DOWNPOURS...SMALL HAIL...FREQUENT LIGHTNING...AND GUSTY
WINDS FROM A STORM IN THAT AREA. THESE CONDITIONS CAN BE EXPECTED TO
OCCUR WITH THUNDERSTORM ACTIVITY THROUGHOUT THIS AFTERNOON AND EARLY
EVENING.

PEOPLE TRAVELING THROUGH OR PLANNING ANY OUTDOOR ACTIVITIES IN THE
MOUNTAINS TODAY SHOULD BE AWARE OF POSSIBLE THUNDERSTORM ACTIVITY. SEEK
SHELTER IF THUNDERSTORMS APPROACH AND AVOID STREAMS AND GULLEYS WHICH
ARE PRONE TO RAPID FLOODING.

DANIELSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 3:35 PM PDTFlash Flood WarningLOXSan Bernardino115 min

Nearby

Flash Flood Warnings in California, 1996Every flash flood warning in 1996

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.