Alert archive / Missouri / Flash Flood Watches in 2011

Flash Flood Watch 4, NWS St. Louis, MO

May 24, 201129 counties in Missouri; 17 counties in Illinois

NWS St. Louis, MO issued this flash flood watch at May 24, 2011, 3:44 PM CDT for 29 counties in Missouri; 17 counties in Illinois. It took effect at May 24, 2011, 7:00 PM CDT. It was in force for 28 hr.

The area

The counties it named.

The facts

Issued
May 24, 2011, 3:44 PM CDT (20:44 UTC)
In effect from
May 24, 2011, 7:00 PM CDT
Expired
May 25, 2011, 11:22 PM CDT
In force
28 hr
Issued by
NWS St. Louis, MO
Flood severity
None
All 46 counties

Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Clinton County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Madison County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Shelby County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 18 km from the middle of the area, began a volume at 20:46 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, 8.7 hours before the alert went out and 241 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 2011-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 518 joules per kilogram.LCLLFCEL10008507005003002001001 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 2011-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -14 square meters per square second.19395878Sfc1 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
518 J/kg
Mixed-layer CIN
-69 J/kg
Mixed-layer LCL
941 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

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

351 
WGUS63 KLSX 242044
FFALSX

URGENT - IMMEDIATE BROADCAST REQUESTED
FLOOD WATCH
NATIONAL WEATHER SERVICE ST LOUIS MO
344 PM CDT TUE MAY 24 2011

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-251000-
/O.NEW.KLSX.FF.A.0004.110525T0000Z-110526T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
INCLUDING THE CITIES OF...LITCHFIELD...VANDALIA...SALEM...
CHESTER...QUINCY...EDWARDSVILLE...BELLEVILLE...HANNIBAL...
BOWLING GREEN...COLUMBIA...MEXICO...JEFFERSON CITY...ST CHARLES...
UNION...ST LOUIS...FARMINGTON
344 PM CDT TUE MAY 24 2011

...FLASH FLOOD WATCH IN EFFECT FROM 7 PM CDT THIS EVENING THROUGH
LATE WEDNESDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* FLASH FLOOD WATCH FOR PORTIONS OF ILLINOIS AND MISSOURI...
  INCLUDING THE FOLLOWING COUNTIES...IN ILLINOIS...ADAMS IL...
  BOND IL...BROWN IL...CALHOUN IL...CLINTON IL...FAYETTE IL...
  GREENE IL...JERSEY IL...MACOUPIN IL...MADISON IL...MARION 
  IL...MONROE IL...MONTGOMERY IL...PIKE IL...RANDOLPH IL...ST. 
  CLAIR IL AND WASHINGTON IL. IN MISSOURI...AUDRAIN MO...BOONE 
  MO...CALLAWAY MO...COLE MO...CRAWFORD MO...FRANKLIN MO...
  GASCONADE MO...IRON MO...JEFFERSON MO...KNOX MO...LEWIS MO...
  LINCOLN MO...MADISON MO...MARION MO...MONITEAU MO...MONROE 
  MO...MONTGOMERY MO...OSAGE MO...PIKE MO...RALLS MO...REYNOLDS 
  MO...SHELBY MO...ST. CHARLES MO...ST. FRANCOIS MO...ST. LOUIS 
  CITY MO...ST. LOUIS MO...STE. GENEVIEVE MO...WARREN MO AND 
  WASHINGTON MO.

* FROM 7 PM CDT THIS EVENING THROUGH LATE WEDNESDAY NIGHT

* SEVERAL WAVES OF THUNDERSTORMS WILL MOVE ACROSS THE REGION FROM
  TONIGHT INTO WEDNESDAY EVENING. THESE STORMS WILL BE CAPABLE OF
  PRODUCING VERY HEAVY RAINFALL RATES WHICH MAY CAUSE FLASH
  FLOODING...ESPECIALLY WHERE THESE STORMS MOVE OVER THE SAME
  LOCATIONS.

* HEAVY RAINFALL ON INCREASINGLY SATURATED SOILS WILL CAUSE RAPID
  RUNOFF OF WATER. THIS WILL CAUSE RAPID RISES ON LOCAL STREAMS
  AND CREEKS THAT COULD FLOOD HIGHWAYS AND SECONDARY ROADS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT FLASH FLOODING IS POSSIBLE BUT NOT
IMMINENT IN THE WATCH AREA. PEOPLE IN THE WATCH AREA SHOULD BE
AWARE OF THE POSSIBILITY OF HEAVY RAINFALL AND FLASH FLOODING.
CHECK YOUR PREPAREDNESS REQUIREMENTS...ESPECIALLY IF YOU LIVE IN
FLOOD PRONE AREAS. STAY INFORMED...AND BE READY FOR QUICK ACTION
IF FLOODING IS OBSERVED OR IF A FLASH FLOOD WARNING IS ISSUED.

&&

$$

BRITT
2 follow-up statements
994 
WGUS63 KLSX 250933
FFALSX

FLOOD WATCH
NATIONAL WEATHER SERVICE ST LOUIS MO
433 AM CDT WED MAY 25 2011

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-252200-
/O.CON.KLSX.FF.A.0004.000000T0000Z-110526T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
INCLUDING THE CITIES OF...LITCHFIELD...VANDALIA...SALEM...
CHESTER...QUINCY...EDWARDSVILLE...BELLEVILLE...HANNIBAL...
BOWLING GREEN...COLUMBIA...MEXICO...JEFFERSON CITY...ST CHARLES...
UNION...ST LOUIS...FARMINGTON
433 AM CDT WED MAY 25 2011

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF ILLINOIS AND MISSOURI...INCLUDING THE FOLLOWING 
  COUNTIES...IN ILLINOIS...ADAMS IL...BOND IL...BROWN IL...
  CALHOUN IL...CLINTON IL...FAYETTE IL...GREENE IL...JERSEY 
  IL...MACOUPIN IL...MADISON IL...MARION IL...MONROE IL...
  MONTGOMERY IL...PIKE IL...RANDOLPH IL...ST. CLAIR IL AND 
  WASHINGTON IL. IN MISSOURI...AUDRAIN MO...BOONE MO...CALLAWAY 
  MO...COLE MO...CRAWFORD MO...FRANKLIN MO...GASCONADE MO...
  IRON MO...JEFFERSON MO...KNOX MO...LEWIS MO...LINCOLN MO...
  MADISON MO...MARION MO...MONITEAU MO...MONROE MO...MONTGOMERY 
  MO...OSAGE MO...PIKE MO...RALLS MO...REYNOLDS MO...SHELBY 
  MO...ST. CHARLES MO...ST. FRANCOIS MO...ST. LOUIS CITY MO...
  ST. LOUIS MO...STE. GENEVIEVE MO...WARREN MO AND WASHINGTON 
  MO.

* THROUGH LATE TONIGHT

* SEVERAL WAVES OF THUNDERSTORMS WILL MOVE ACROSS THE REGION
  THROUGH THIS EVENING. THESE STORMS WILL BE CAPABLE OF PRODUCING
  VERY HEAVY RAINFALL RATES WHICH MAY CAUSE FLASH FLOODING...
  ESPECIALLY WHERE THESE STORMS MOVE OVER THE SAME LOCATIONS.

* HEAVY RAINFALL ON INCREASINGLY SATURATED SOILS WILL CAUSE 
  RAPID RUNOFF OF WATER. THIS WILL CAUSE RAPID RISES ON LOCAL 
  STREAMS AND CREEKS THAT COULD FLOOD HIGHWAYS AND SECONDARY 
  ROADS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT FLASH FLOODING IS POSSIBLE BUT NOT
IMMINENT IN THE WATCH AREA. PEOPLE IN THE WATCH AREA SHOULD BE
AWARE OF THE POSSIBILITY OF HEAVY RAINFALL AND FLASH FLOODING.
CHECK YOUR PREPAREDNESS REQUIREMENTS...ESPECIALLY IF YOU LIVE IN
FLOOD PRONE AREAS. STAY INFORMED...AND BE READY FOR QUICK ACTION
IF FLOODING IS OBSERVED OR IF A FLASH FLOOD WARNING IS ISSUED.

&&

$$

BYRD
900 
WGUS63 KLSX 260422
FFALSX

FLOOD WATCH
NATIONAL WEATHER SERVICE ST LOUIS MO
1122 PM CDT WED MAY 25 2011

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-260530-
/O.CAN.KLSX.FF.A.0004.000000T0000Z-110526T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
INCLUDING THE CITIES OF...LITCHFIELD...VANDALIA...SALEM...
CHESTER...QUINCY...EDWARDSVILLE...BELLEVILLE...HANNIBAL...
BOWLING GREEN...COLUMBIA...MEXICO...JEFFERSON CITY...ST CHARLES...
UNION...ST LOUIS...FARMINGTON
1122 PM CDT WED MAY 25 2011

...FLASH FLOOD WATCH IS CANCELLED...

THE FLASH FLOOD WATCH FOR PORTIONS OF WEST CENTRAL AND SOUTHWEST
ILLINOIS AS WELL AS EASTERN AND CENTRAL AND MISSOURI HAS BEEN
CANCELLED. ALTHOUGH SHOWERS ARE STILL LIKELY FOR MUCH OF THIS
AREA FOR THE REMAINDER OF THE NIGHT MOST OF THESE WILL BE ON THE
LIGHT SIDE AND SHOULD NOT POSE A THREAT OF FLOODING.


$$

GKS

Nearby

Flash Flood Watches in Missouri, 2011Flash Flood Watches in Illinois, 2011Every flash flood watch 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.