Alert archive / California / Flash Flood Warnings in 1998

Flash Flood Warning 33, NWS Los Angeles, CA

May 5, 1998San Luis Obispo County, Santa Barbara County, California

NWS Los Angeles, CA issued this flash flood warning at May 5, 1998, 7:55 PM PDT for San Luis Obispo County, Santa Barbara County, California. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 5, 1998, 7:55 PM PDT (02:55 UTC)
Expired
May 5, 1998, 10:00 PM PDT
In force
2 hr
Issued by
NWS Los Angeles, CA
Area
Whole counties

Counties San Luis Obispo County, CA, Santa Barbara County, CA

The nearest sounding before it

Vandenberg AFB, CA (KVBG), launched 00:00Z, 2.9 hours before the alert went out and 35 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, Vandenberg AFB, CA at 00:00Z on 1998-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 370 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, Vandenberg AFB, CA at 00:00Z on 1998-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 square meters per square second.1939587897117Sfc1 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
370 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
789 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
11 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 060331
FFWLAX
CAC083-060330-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE OXNARD CA
830 PM PDT TUE MAY 5 1998

THE NATIONAL WEATHER SERVICE IN OXNARD HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  EASTERN LOS ANGELES COUNTY MOUNTAINS AND ADJACENT FOOTHILLS

* UNTIL 1000 PM PDT

* AT 825 PM...DOPPLER RADARS INDICATED A STRONG LINE OF
  SHOWERS ACROSS THE EASTERN SAN GABRIEL MOUNTAINS AND
  ADJACENT FOOTHILL COMMUNITIES. THE LINE OF STORMS WAS MOVING
  SLOWLY EASTWARD TOWARDS THE LOS ANGELES/SAN BERNARDINO COUNTY
  LINE. ANOTHER BAND OF SHOWERS IS MOVING INTO THE LOS ANGELES
  BASIN...AND IS EXPECTED TO INTENSIFY OVER THE FOOTHILL AND
  MOUNTAIN AREAS AFTER 9 PM. AS A RESULT...THE FLASH FLOOD
  WARNING HAS BEEN EXTENDED FOR THE ABOVE AREAS UNTIL 10 PM.

* BETWEEN 830 PM AND 10 PM...MOUNTAIN AND ADJACENT FOOTHILL
  AREAS FROM HIGHWAY 39 AND EASTWARD WILL LIKELY EXPERIENCE FLASH
  FLOODING.  AFFECTED COMMUNITIES WILL INCLUDE AZUSA...GLENDORA...
  AND SAN DIMAS...AS WELL AS THE MORRIS RESERVOIR AREA.
  EVENING COMMUTES ALONG FOOTHILL BOULEVARD...INTERSTATE 210...AND
  HIGHWAY 39 WILL LIKELY HAVE FLOODED ROAD CONDITIONS.

A FLASH FLOOD WARNING MEANS THHAT FLASH FLOODING IS OCCURRING OR
IS IMMINENT. MOVE TO HIGHER GROUND IMMEDIATELY IF FLOODING IS
ENCOUNTERED. 

GOMBERG

The office that day

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

IssuedProductOfficeCountiesLasted
May 5, 5:30 PM PDTFlash Flood WarningLOXSan Luis Obispo, Santa Barbara90 min
May 5, 7:00 PM PDTFlash Flood WarningLOXSan Luis Obispo, Santa Barbara60 min
May 5, 7:20 PM PDTFlash Flood WarningLOXLos Angeles70 min
May 5, 8:30 PM PDTFlash Flood WarningLOXLos Angeles90 min
May 5, 9:50 PM PDTFlash Flood WarningLOXSan Luis Obispo, Santa Barbara2 hr
May 5, 9:55 PM PDTFlash Flood WarningLOXLos Angeles2 hr
May 5, 11:55 PM PDTFlash Flood WarningLOXLos Angeles2 hr
May 6, 1:55 AM PDTFlash Flood WarningLOXLos Angeles2 hr

Nearby

Flash Flood Warnings in California, 1998Every flash flood warning in 1998

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.