Alert archive / Illinois / Flash Flood Warnings in 2011

Flash Flood Warning 76, NWS St. Louis, MO

July 12, 2011Randolph County, Illinois

NWS St. Louis, MO issued this flash flood warning at Jul 12, 2011, 7:50 PM CDT for Randolph County, Illinois. It was in force for 3 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 12, 2011, 7:50 PM CDT (00:50 UTC)
Expired: Jul 12, 2011, 10:42 PM CDT
In force: 3 hr
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Flood severity: None

County Randolph County, IL

The radar

The St Louis radar (KLSX), 107 km from the middle of the area, began a volume at 00:51 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.

What was reported inside it

Time	Report	Where	Remark
Jul 12, 7:52 PM CDT	FLASH FLOOD	4 Se Eden, IL	WATER FLOWING OVER COUNTY LINE ROAD AT HWY 154
Jul 12, 7:52 PM CDT	FLASH FLOOD	7 Se Walsh, IL	CAR STRANDED IN WATER.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.8 hours before the alert went out and 266 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: 574 J/kg
Mixed-layer CIN: -175 J/kg
Mixed-layer LCL: 1488 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 137 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.

057 
WGUS53 KLSX 130050
FFWLSX
ILC157-130400-
/O.NEW.KLSX.FF.W.0076.110713T0050Z-110713T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
750 PM CDT TUE JUL 12 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  RANDOLPH COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 1100 PM CDT

* AT 750 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. 1 TO 3 INCHES OF RAINFALL HAS OCCURRED THIS EVENING   
  AND AN ADDITIONAL INCH OF RAINFALL IS POSSIBLE.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  CHESTER...SPARTA...BREMEN...COULTERVILLE...EVANSVILLE...PERCY AND
  STEELEVILLE.

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.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 3800 8959 3790 8985 3787 8990 3787 8994
      3793 8998 3795 8993 3797 8994 3796 9000
      3802 9005 3802 9011 3822 8960

$$

CVKING

1 follow-up statement

854 
WGUS73 KLSX 130342
FFSLSX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1042 PM CDT TUE JUL 12 2011

ILC157-130357-
/O.CAN.KLSX.FF.W.0076.000000T0000Z-110713T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
RANDOLPH IL-
1042 PM CDT TUE JUL 12 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR RANDOLPH COUNTY 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...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 3800 8959 3790 8985 3787 8990 3787 8994
      3793 8998 3795 8993 3797 8994 3796 9000
      3802 9005 3802 9011 3822 8960

$$

TES

Nearby

Flash Flood Warnings in Illinois, 2011 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.