Alert archive / California / Flash Flood Warnings in 1991

Flash Flood Warning 2, NWS San Diego, CA

September 5, 1991Imperial County, San Diego County, California

NWS San Diego, CA issued this flash flood warning at Sep 5, 1991, 6:00 PM PDT for Imperial County, San Diego County, California. It was in force for .

The area

The counties it named.

The facts

Issued
Sep 5, 1991, 6:00 PM PDT (01:00 UTC)
Expired
Sep 5, 1991, 6:00 PM PDT
In force
Issued by
NWS San Diego, CA
Area
Whole counties

Counties Imperial County, CA, San Diego County, CA

The nearest sounding before it

San Diego, CA (KNKX), launched 00:00Z, 1.0 hours before the alert went out and 109 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 1991-09-06Temperature 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 00:00Z on 1991-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -26 square meters per square second.193958Sfc1 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
1401 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-26 m²/s²
0-3 km storm-relative helicity
-50 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 
TTAACA KSAN 060057
FFWSAN
CAC025-073-060100-

BULLETIN - EBS ACTIVATION REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
600 PM PDT THU SEP 5 1991

THE NATIONAL WEATHER SERVICE IN SAN DIEGO IS EXTENDING
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
EFFECTIVE UNTIL  700 PM PDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...

IN SOUTHEAST CALIFORNIA

   ...NORTHWESTERN IMPERIAL COUNTY

IN SOUTHWEST CALIFORNIA

   ...NORTHEASTERN SAN DIEGO COUNTY
RADAR AND SATELLITE SHOW THUNDERSTORMS WITH HEAVY RAINS ARE CONTINUING
OVER MOUNT PALOMAR...WARNER SPRINGS...BORREGO SPRING AND MOUNT LAGUNA.
PEOPLE IN THESE AREAS ARE ADVISED THAT THE RAINS ARE PRODUCING MUD
SLIDES THAT HAVE PROMPTED THE CALIFORNIA HIGHWAY PATROL TO CLOSE
SECTIONS OF HIGHWAY 79 AND 76.


SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

CEGIEL

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, Sep 5, 12:25 PM PDT, 5 hours 35 minutes before
CAZ-ALL-060100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
1230 PM PDT THU SEP 05 1991

NOON SATELLITE PICTURES SHOW THE MOST ACTIVE AREA OF DEVELOPING
THUNDERSTORMS ARE OVER NORTHERN SAN DIEGO COUNTY FROM OCEANSIDE TO
MT PALOMAR IN SAN DIEGO COUNTY.   RADAR INDICATES LIGHT RAINFALL.

WEATHER CONDITIONS...HOWEVER...POINT TO A RESURGENCE OF THUNDERSTORM
ACTIVITY TODAY AND THIS EVENING.  A LOW PRESSURE LOCATED JUST OFF THE
SAN DIEGO COAST COMBINING WITH A VERY WARM AND MOIST FLOW FROM MEXICO
ARE RESPONSIBLE FOR VERY UNSTABLE CONDITIONS OVER SAN DIEGO COUNTY
AND SOUTHERN CALIFORNIA.  THUNDERSTORMS WILL INCREASE THIS AFTERNOON
AS THE HEATING OF THE DAY CONTRIBUTES FURTHER TO THE INSTABILITY.

SOME OF THESE DEVELOPING THUNDERSTORMS HAVE THE POTENTIAL OF PRODUCING
LOCALLY HEAVY RAINS...GUSTY WINDS AND EVEN HAIL.   CAUTION SHOULD BE
EXERCISED IF THESE CONDITIONS DEVELOP ANYWHERE IN SAN DIEGO AND
IMPERIAL COUNTIES INCLUDING THE REST OF SOUTHERN CALIFORNIA.
.
THUNDERSTORMS WILL GRADUALLY DIMINISH AND BE CONFINED TO THE MOUNTAINS
AND DESERTS FRIDAY AS THE LOW PRESSURE SLOWLY MOVES EAST OF SAN DIEGO.
FURTHER DRYING WILL DEVELOP THIS WEEKEND AS HIGH LEVEL WINDS BECOME
MORE SOUTHWESTERLY AND DRIER.

SHIGEHARA

Nearby

Flash Flood Warnings in California, 1991Every flash flood warning in 1991

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.