Alert archive / Missouri / Flash Flood Warnings in 1993

Flash Flood Warning 68, NWS St. Louis, MO

September 23, 1993Saint Louis County, City of Saint Louis, Missouri

NWS St. Louis, MO issued this flash flood warning at Sep 23, 1993, 7:41 AM CDT for Saint Louis County, City of Saint Louis, Missouri. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Sep 23, 1993, 7:41 AM CDT (12:41 UTC)
Expired
Sep 23, 1993, 10:45 AM CDT
In force
3 hr
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties City of Saint Louis, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 32 km from the middle of the area, began a volume at 12:41 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

Springfield, MO (KUMN), launched 12:00Z, 0.7 hours before the alert went out and 362 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, Springfield, MO at 12:00Z on 1993-09-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1898 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, Springfield, MO at 12:00Z on 1993-09-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 137 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
1898 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
756 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
137 m²/s²
0-3 km storm-relative helicity
144 m²/s²
Significant tornado parameter
0.8
Supercell composite
4.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 231243
FFWSTL
MOC071-099-183-189-510-231545-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
741 AM CDT THU SEP 23 1993
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 1045 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN EAST CENTRAL MISSOURI
 
   ...FRANKLIN COUNTY...JEFFERSON COUNTY...ST CHARLES COUNTY
   ...ST LOUIS COUNTY
 
  AND THE INDEPENDENT CITY OF
 
   ...ST LOUIS CITY
 
AT 740 A CDT NWS DOPPLER RADAR INDICATED A LINE OF STRONG THUNDERSTORMS
PRODUCING VERY HEAVY RAIN FROM 22 MILES WEST OF DOWNTOWN ST. LOUIS TO
65 MILES SOUTHWEST OF ST. LOUIS. THE LINE WAS MOVING EAST AT 30 MILES AN
HOUR.
 
THIS LINE WILL LIKELY DROP ANOTHER 1 TO 2 INCHES OF RAIN. FLASH FLOODING
IS IMMINEMT!
 
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...tOR 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.
 
JPK

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 23, 6:30 AM CDT, 1 hour 11 minutes before
MOZ009-010-011-014-231230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE COLUMBIA MO
630 AM CDT THU SEP 23 1993

...A FLASH FLOOD WATCH IS IN EFFECT THROUGH THE MORNING...

AT 625 AM CDT WEATHER RADAR SHOWED THUNDERSTORMS WITH VERY HEAVY
SHOWERS MOVING THROUGH CENTRAL MISSOURI...IN COLUMBIA AND WITHIN
A 20 MILE RADIUS OF THE CITY.  THESE STORMS PRODUCED .25 OF AN INCH
OF RAIN IN 15 MINUTES AT THE REGIONAL AIRPORT JUST SOUTH OF COLUMBIA.

THE GENERAL AREA OF MOSTLY LIGHT TO MODERATE SHOWERS COVERED THE NORTH
HALF OF MISSOURI AND EXTENDED INTO SOUTHEAST MISSOURI BETWEEN FORT
LEONARD WOOD..CAPE GIRARDEAU AND ST. LOUIS.

THE THUNDERSTORMS WERE MOVING TO THE SOUTHEAST AROUND 30 MILES AN
HOUR.

LB
Special weather statement, Sep 23, 6:32 AM CDT, 1 hour 9 minutes before
MOZ009-010-011-014-231230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE COLUMBIA MO
630 AM CDT THU SEP 23 1993

...A FLASH FLOOD WATCH IS IN EFFECT THROUGH THE MORNING...

AT 625 AM CDT WEATHER RADAR SHOWED THUNDERSTORMS WITH VERY HEAVY
SHOWERS MOVING THROUGH CENTRAL MISSOURI...IN COLUMBIA AND WITHIN
A 20 MILE RADIUS OF THE CITY.  THESE STORMS PRODUCED .25 OF AN INCH
OF RAIN IN 15 MINUTES AT THE REGIONAL AIRPORT JUST SOUTH OF COLUMBIA.

THE GENERAL AREA OF MOSTLY LIGHT TO MODERATE SHOWERS COVERED THE NORTH
HALF OF MISSOURI AND EXTENDED INTO SOUTHEAST MISSOURI BETWEEN FORT
LEONARD WOOD..CAPE GIRARDEAU AND ST. LOUIS.

THE THUNDERSTORMS WERE MOVING TO THE SOUTHEAST AROUND 30 MILES AN
HOUR.

LB

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 22, 8:35 PM CDTFlash Flood WarningLSXSaint Charles, Saint Louis, Warren3 hr
Sep 22, 8:35 PM CDTFlash Flood WarningLSXCity of Saint Louis3 hr
Sep 22, 9:25 PM CDTFlash Flood WarningLSXFranklin3 hr
Sep 23, 1:19 AM CDTFlash Flood WarningLSXCrawford, Saint Francois, Washington4 hr
Sep 23, 2:34 AM CDTFlash Flood WarningLSXFranklin4 hr
Sep 23, 3:14 AM CDTFlash Flood WarningLSXJefferson4 hr
Sep 23, 7:41 AM CDTFlash Flood WarningLSXFranklin, Jefferson3 hr
Sep 23, 7:41 AM CDTFlash Flood WarningLSXSaint Charles3 hr
Sep 23, 8:41 AM CDTFlash Flood WarningLSXPerry, Sainte Genevieve, Saint Francois, Washington3 hr
Sep 23, 8:55 AM CDTFlash Flood WarningLSXWarren110 min
Sep 23, 10:24 AM CDTFlash Flood WarningLSXCrawford4 hr

Nearby

Flash Flood Warnings in Missouri, 1993Every flash flood warning in 1993

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.