Alert archive / Illinois / Flash Flood Warnings in 2011

Flash Flood Warning 5, NWS St. Louis, MO

April 22, 20114 counties in Illinois; 4 counties in Missouri

NWS St. Louis, MO issued this flash flood warning at Apr 22, 2011, 7:28 AM CDT for 4 counties in Illinois; 4 counties in Missouri. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 22, 2011, 7:28 AM CDT (12:28 UTC)
Expired
Apr 22, 2011, 1:30 PM CDT
In force
6 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Monroe County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Jefferson County, MO, Saint Francois County, MO, Sainte Genevieve County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 79 km from the middle of the area, began a volume at 12:28 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

Lincoln, IL (KILX), launched 12:00Z, 0.5 hours before the alert went out and 290 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, Lincoln, IL at 12:00Z on 2011-04-22Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2011-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 585 square meters per square second.1939587897Sfc1 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
845 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
585 m²/s²
0-3 km storm-relative helicity
683 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.

230 
WGUS53 KLSX 221228
FFWLSX
ILC133-157-163-189-MOC099-186-187-221-221830-
/O.NEW.KLSX.FF.W.0005.110422T1228Z-110422T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
728 AM CDT FRI APR 22 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN RANDOLPH COUNTY IN SOUTHWEST ILLINOIS...
  NORTHERN STE. GENEVIEVE COUNTY IN SOUTHEAST MISSOURI...
  SOUTHEASTERN ST. CLAIR COUNTY IN SOUTHWEST ILLINOIS...
  SOUTHERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...
  SOUTHERN MONROE COUNTY IN SOUTHWEST ILLINOIS...
  SOUTHWESTERN WASHINGTON COUNTY IN SOUTH CENTRAL ILLINOIS...
  ST. FRANCOIS COUNTY IN SOUTHEAST MISSOURI...
  WASHINGTON COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 130 PM CDT FRIDAY

* AT 727 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RADAR ESTIMATES THAT 2 TO 4 INCHES OF RAIN HAS        
  ALREADY FALLEN OVER THE WARNED AREA. ADDITIONAL THUNDERSTORMS WITH 
  HEAVY RAINFALL WILL LEAD TO FLASH FLOODING.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...BONNE
  TERRE...DE SOTO...POTOSI...RED BUD...SPARTA...BALDWIN...
  BLOOMSDALE...COULTERVILLE...COURTOIS...EVANSVILLE...LIVELY GROVE...
  MARISSA...MINERAL POINT...NEW ATHENS...NEW DESIGN...OLD MINES...
  OLYMPIAN VILLAGE AND TILDEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 3775 9111 3801 9110 3843 8960 3808 8960

$$

CVKING
1 follow-up statement
307 
WGUS73 KLSX 221750
FFSLSX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1250 PM CDT FRI APR 22 2011

MOC099-186-187-221-221757-
/O.CAN.KLSX.FF.W.0005.000000T0000Z-110422T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ST. FRANCOIS MO-STE. GENEVIEVE MO-WASHINGTON MO-JEFFERSON MO-
1250 PM CDT FRI APR 22 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHERN
JEFFERSON...WASHINGTON...NORTHERN STE. GENEVIEVE AND ST. FRANCOIS
COUNTIES IS CANCELLED...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO 
RECEDE...AND LAW ENFORCEMENT THROUGHOUT SOUTHEAST MISSOURI HAVE NOT 
RECEIVED ANY REPORTS OF FLOODING OR CLOSED ROADS.

HOWEVER...A FLASH FLOOD WATCH REMAINS IN EFFECT AS ANOTHER ROUND OF 
INTENSE THUNDERSTORMS ARE EXPECTED LATE THIS AFTERNOON AND EARLY 
THIS EVENING.  THESE STORMS COULD POSE ANOTHER DANGER OF FLASH 
FLOODING...SO PEOPLE THROUGHOUT THE AREA ARE URGED TO MONITOR 
WEATHER DEVELOPMENTS INTO THE EARLY EVENING HOURS.

LAT...LON 3799 9003 3821 9036 3843 8960 3808 8960

$$

ILC133-157-163-189-221830-
/O.CON.KLSX.FF.W.0005.000000T0000Z-110422T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
RANDOLPH IL-WASHINGTON IL-MONROE IL-ST. CLAIR IL-
1250 PM CDT FRI APR 22 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHEASTERN ST.
CLAIR...SOUTHERN MONROE...SOUTHWESTERN WASHINGTON AND NORTHERN
RANDOLPH COUNTIES UNTIL 130 PM CDT...

NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT SCATTERED 
THUNDERSTORMS WITH BRIEF HEAVY DOWNPOURS HAVE MOVED FROM RED BUD TO 
JUST EAST OF MARISSA SINCE 12 NOON....BUT ARE GETTING READY TO EXIT 
THE WARNING AREA...PRODUCING SPOTTY RAINS OF AROUND ONE-HALF INCH.
 HOWEVER...SOUTH OF A RED BUD....MARISSA LINE...NO HEAVY RAIN HAS 
BEEN REPORTED SINCE AROUND 8 AM.  

IF CURRENT TRENDS CONTINUE...THE THREAT OF FLASH FLOODING WILL 
TEMPORARILY SUBSIDE EARLY THIS AFTERNOON. HOWEVER...A FLASH FLOOD 
WATCH REMAINS IN EFFECT AS ANOTHER ROUND OF INTENSE THUNDERSTORMS 
ARE EXPECTED LATE THIS AFTERNOON AND EARLY THIS EVENING.  THESE 
STORMS COULD POSE ANOTHER DANGER OF FLASH FLOODING...SO PEOPLE 
THROUGHOUT THE AREA ARE URGED TO MONITOR WEATHER DEVELOPMENTS INTO 
THE EARLY EVENING HOURS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLASH FLOODING IS IMMINENT OR
OCCURRING. IF YOU ARE IN THE WARNING AREA...MOVE TO HIGHER GROUND
IMMEDIATELY. RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE
IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO
CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 3799 9003 3821 9036 3843 8960 3808 8960

$$

TRUETT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 22, 7:12 AM CDTAreal Flood AdvisoryLSXRandolph3 hr
Apr 22, 7:17 AM CDTAreal Flood AdvisoryLSXMonroe3 hr
Apr 22, 8:51 AM CDTSevere Thunderstorm WarningLSXAdams, Brown, Pike39 min
Apr 22, 9:16 AM CDTSevere Thunderstorm WarningLSXCalhoun, Greene, Jersey, Pike44 min
Apr 22, 9:36 AM CDTFlash Flood WarningLSXAdams, Brown, Pike3 hr
Apr 22, 9:59 AM CDTSevere Thunderstorm WarningLSXCalhoun, Greene, Jersey, Macoupin, Madison, Montgomery and 1 more46 min
Apr 22, 10:17 AM CDTSevere Thunderstorm WarningLSXCalhoun43 min
Apr 22, 10:56 AM CDTSevere Thunderstorm WarningLSXBond, Clinton, Fayette, Macoupin, Madison, Montgomery and 1 more49 min
Apr 22, 11:00 AM CDTSevere Thunderstorm WarningLSXMonroe, Saint Clair45 min
Apr 22, 11:41 AM CDTAreal Flood AdvisoryLSXBond, Fayette, Macoupin, Madison, Montgomery3 hr
Apr 22, 11:44 AM CDTSevere Thunderstorm WarningLSXClinton, Madison, Monroe, Saint Clair, Washington46 min
Apr 22, 12:21 PM CDTSevere Thunderstorm WarningLSXBond, Fayette39 min
Apr 22, 1:33 PM CDTRiver Flood WarningLSXBrown22 hr
Apr 22, 6:55 PM CDTTornado WarningLSXCalhoun50 min
Apr 22, 6:58 PM CDTSevere Thunderstorm WarningLSXJersey, Macoupin, Madison47 min
Apr 21, 9:24 PM CDTRiver Flood WarningLSXGasconade, Montgomery11 days
Apr 21, 10:14 PM CDTRiver Flood WarningLSXReynolds9 days
Apr 22, 8:47 AM CDTSevere Thunderstorm WarningLSXBoone, Callaway, Cole, Moniteau, Osage43 min
Apr 22, 9:28 AM CDTSevere Thunderstorm WarningLSXCallaway, Lincoln, Montgomery, Pike, Warren47 min
Apr 22, 9:32 AM CDTSevere Thunderstorm WarningLSXCallaway, Cole, Franklin, Gasconade, Lincoln, Montgomery and 2 more43 min
Apr 22, 12:34 PM CDTRiver Flood WarningLSXSaint Charles26 hr
Apr 22, 2:39 PM CDTRiver Flood WarningLSXMarion37 hr
Apr 22, 4:32 PM CDTSevere Thunderstorm WarningLSXCole, Moniteau43 min
Apr 22, 4:40 PM CDTTornado WarningLSXCole, Moniteau50 min
Apr 22, 5:10 PM CDTSevere Thunderstorm WarningLSXCrawford, Franklin, Gasconade39 min
Apr 22, 5:12 PM CDTTornado WarningLSXBoone, Callaway, Cole48 min
Apr 22, 5:49 PM CDTTornado WarningLSXCallaway, Gasconade, Montgomery, Osage41 min
Apr 22, 6:05 PM CDTSevere Thunderstorm WarningLSXCole, Osage40 min
Apr 22, 6:22 PM CDTTornado WarningLSXFranklin, Gasconade, Lincoln, Montgomery, Warren38 min
Apr 22, 6:36 PM CDTSevere Thunderstorm WarningLSXFranklin, Gasconade, Osage39 min

Nearby

Flash Flood Warnings in Illinois, 2011Flash Flood Warnings in Missouri, 2011Every flash flood warning in 2011

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.