Alert archive / Illinois / Flash Flood Warnings in 2011

Flash Flood Warning 68, NWS St. Louis, MO

July 4, 2011Randolph County, Illinois

NWS St. Louis, MO issued this flash flood warning at Jul 4, 2011, 4:15 AM CDT for Randolph County, Illinois. It was in force for 6 hr. 1 report 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 4, 2011, 4:15 AM CDT (09:15 UTC)
Expired: Jul 4, 2011, 10:00 AM CDT
In force: 6 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), 104 km from the middle of the area, began a volume at 09:15 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 4, 7:00 AM CDT	HEAVY RAIN 2.55	2 Ssw Sparta, IL	COCORAHS REPORT

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, 9.3 hours before the alert went out and 265 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: 701 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 1468 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 27 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.5

Open this sounding in Storm Lab

The text

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

770 
WGUS53 KLSX 040915
FFWLSX
ILC157-041500-
/O.NEW.KLSX.FF.W.0068.110704T0915Z-110704T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
415 AM CDT MON JUL 4 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

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

* UNTIL 1000 AM CDT

* AT 410 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE
  WARNED AREA.  DOPPLER RADAR HAS INDICATED THAT 2 TO 3 INCHES OF
  RAIN HAS FALLEN FROM KELLOGG TO ELLIS GROVE TO SPARTA SINCE 2 AM.
  THIS RAIN IS FALLING ON GROUND SATURATED FROM RECENT RAINS AND IS
  LIKELY CAUSING CREEKS AND STREAMS TO RISE QUICKLY OUT OF THEIR
  BANKS AS WELL AS FLOODING OF SOME ROADS.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...  
  MODOC...KELLOGG...ELLIS GROVE...NEW PALESTINE...EVANSVILLE...
  PRESTON AND SPARTA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. DO
NOT ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND TO
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN
WATER BEGINS RISING.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 3790 8984 3790 8985 3786 8992 3792 8998
      3796 8993 3797 8994 3796 9000 3802 9006
      3802 9008 3807 9013 3822 8979 3822 8960
      3800 8959

$$

BRITT

1 follow-up statement

661 
WGUS73 KLSX 041215
FFSLSX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
715 AM CDT MON JUL 4 2011

ILC157-041500-
/O.CON.KLSX.FF.W.0068.000000T0000Z-110704T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
RANDOLPH IL-
715 AM CDT MON JUL 4 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR RANDOLPH COUNTY UNTIL
1000 AM CDT...

AT 706 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT THE THUNDERSTORMS THAT PRODUCED 2 TO 3 INCHES OF RAINFALL 
BETWEEN 2 AND 4 AM HAVE MOVED OUT OF THE AREA.  WHILE THE RAIN HAS 
ENDED...IT IS STILL LIKELY THAT WATER REMAINS ON RURAL ROADS THAT 
LIE ALONG FLOODED CREEKS AND STREAMS.  

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...ELLIS 
GROVE...MODOC...EVANSVILLE...SPARTA...EVANSVILLE AND KELLOGG.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS 
SAFELY.

REPORT FLOODING TO THE NEAREST LAW ENFORCEMENT AGENCY SO THAT THEY
MAY TAKE APPROPRIATE ACTION TO CLOSE FLOODED ROADWAYS. THEY WILL
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN ST LOUIS.

&&

LAT...LON 3800 8959 3790 8985 3786 8991 3787 8993
      3792 8998 3796 8993 3797 8994 3796 9000
      3802 9006 3809 9004 3817 8985 3817 8959
      3816 8960

$$

BRITT

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 4, 3:35 AM CDT	Areal Flood Advisory	LSX	Monroe, Randolph	3 hr

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.