Alert archive / Illinois / Flash Flood Warnings in 1994

Flash Flood Warning 12, NWS St. Louis, MO

April 11, 1994Calhoun County, Illinois; Lincoln County, Missouri

NWS St. Louis, MO issued this flash flood warning at Apr 11, 1994, 8:06 PM CDT for Calhoun County, Illinois; Lincoln County, Missouri. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued: Apr 11, 1994, 8:06 PM CDT (01:06 UTC)
Expired: Apr 12, 1994, 2:00 AM CDT
In force: 6 hr
Issued by: NWS St. Louis, MO
Area: Whole counties

Counties Calhoun County, IL, Lincoln County, MO

The radar

The St Louis radar (KLSX), 47 km from the middle of the area, began a volume at 01:10 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

Paducah/Barkley, KY (KPAH), launched 00:00Z, 1.1 hours before the alert went out and 293 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 427 J/kg
Mixed-layer CIN: -66 J/kg
Mixed-layer LCL: 1170 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 135 m²/s²
0-3 km storm-relative helicity: 180 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 120108
FFWSTL
ILC013-149-MOC113-163-173-120700-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
806 PM CDT MON APR 11 1994
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 200 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHWEST ILLINOIS
 
   ...CALHOUN COUNTY
 
IN WEST CENTRAL ILLINOIS
 
   ...PIKE COUNTY
 
 
IN EAST CENTRAL MISSOURI
 
   ...LINCOLN COUNTY...PIKE COUNTY
 
IN NORTHEAST MISSOURI
 
   ...RALLS COUNTY
 
AN AREA OF HEAVY RAIN WILL BE MOVING INTO EAST CENTRAL AND NORTHEAST
MISSOURI WITHIN THE NEXT HOUR. RAINFALL AMOUNTS OF 1 TO 2 INCHES WILL BE
COMMON. THIS WILL CAUSE FLASH FLOODING ACROSS THE WARNED COUNTIES.
 
AT 800 PM THE LINCOLN COUNTY SHERIFF REPORTED RISING WATER ON MANY
ROADWAYS WITH SOME WASHOUTS OF COUNTY ROADS AS WELL.
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE
THE DANGERS OF FLOODS AND FLDASH FLOODS.  IF FLASH FLOODING IS
OBSERVED...ACT QUICKLY.  MOVE UP TO ESCAPE FLOOD WATERS.  DO
NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.
 
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, Apr 11, 4:16 PM CDT, 3 hours 50 minutes before

MOZALL-120215-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
410 PM CDT MON APR 11 1994

...A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR MUCH OF CENTRAL AND
WEST CENTRAL MISSOURI...

AT 405 PM...THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE
THUNDERSTORM WATCH FOR MUCH OF WEST CENTRAL AND CENTRAL MISSOURI UNTIL
900 PM. THE LARGER CITIES INCLUDED IN THE WATCH ARE
CAMDENTON...JEFFERSON CITY...ROLLA...COLUMBIA AND SEDALIA.

A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITONS ARE FAVORABLE FOR
SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.  SEVERE
THUNDERSTORMS CAN PRODUCE LARGE HAIL AND DAMAGING WINDS...AS WELL AS
VERY HEAVY RAINS AND DEADLY LIGHTNING. PERSONS IN THESE AREAS SHOULD
BE ON THE LOODOUT FOR THREATENING WEATHER CONDITIONS AND LISTERN TO NOAA
WEATHER RADIO OR LOCAL MEDIA SOURCES FOR LATER STATEMENTS AND POSSIBLE
WARNINGS. A TORNADO WATCH CONTINUES IN EFFECT FOR SOUTHWEST MISSOURI
UNTIL 700 PM.
B
GKS

Special weather statement, Apr 11, 5:06 PM CDT, 3 hours before

MOZ061-063-064-120000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
504 PM CDT MON APR 11 1994

...STRONG THUNDERTORMS MOVING INTO THE ST. LOUIS METRO AREA...

AT 500 PM...WEATHER SERVICE RADAR WAS DETECTING A LINE OF THUNDERSTORMS
WITH HEAVY RAINS EXTENDING FROM UNION NORTHEAST THROUGH ST. CHARLES AND
INTO GREENFIELD ILLINOIS.  THESE STORMS WILL CONTINUE MOVING TO THE
NORTHEAST AT 30 TO 35 MPH THROUGH THE ST. LOUIS AREA.  THESE STORMS WILL
PRODUCE HEAVY DOWNPOURS...DANGEROUS LIGHTNING...PEA SIZE HAIL AND STRONG
GUSTY WINDS.

MOTORISTS SHOULD DRIVE WITH EXTREME CAUTION AS PONDING OF WATER ON ROADS
WILL PRODUCE HAZARDOUS DRIVING CONDITIONS.  CONTINUE TO LISTEN TO NOAA
WEATHER RADIO FOR LATER STATEMENTS.

GKS

Special weather statement, Apr 11, 7:47 PM CDT, 19 minutes before

MOZALL-120145-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
745 PM CDT MON APR 11 1994

...THE TORNADO WATCH COVERING SOUTHWEST MISSOURI HAS BEEN ALLOWED TO
EXPIRE...
...THE SEVERE THUNDERSTORM WATCH FOR WEST CENTRAL AND CENTRAL MISSOURI
HAD BEEN CANCELLED...

WHILE THUNDERSTORMS CONTINUE OVER PARTS OF SOUTHWEST AND WEST CENTRAL
MISSOURI...THEY HAVE DECREASED IN INTENSITY AND ARE NOT EXPECTED TO
STRENGTHEN. THUS THE SEVERE WEATHER WATCHES ISSUED EARLIER HAVE BEEN
ALLOWED TO EXPIRE OR HAVE BEEN CANCELLED.

A FLASH FLOOD WATCH CONTINUES FOR SOUTHWEST AND WEST CENTRAL MISSOURI
UNTIL MIDNIGHT. ADDITIONAL RAINFALL OVER THE REMAINDER OF THE EVENING
MAY CAUSE FLASH FLOODING CONSIDERING THE SATURATED CONDITIONS.

JPK

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 11, 8:06 PM CDT	Flash Flood Warning	LSX	Pike	6 hr
Apr 11, 9:26 PM CDT	Flash Flood Warning	LSX	Scott	5 hr
Apr 12, 1:59 AM CDT	Flash Flood Warning	LSX	Calhoun, Pike	6 hr
Apr 12, 1:59 AM CDT	Flash Flood Warning	LSX	Greene, Scott	6 hr
Apr 12, 2:56 AM CDT	Flash Flood Warning	LSX	Monroe	5 hr
Apr 12, 2:56 AM CDT	Flash Flood Warning	LSX	Saint Clair	5 hr

Nearby

Flash Flood Warnings in Illinois, 1994 Flash Flood Warnings in Missouri, 1994 Every flash flood warning in 1994

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.