Alert archive / Illinois / Flash Flood Warnings in 2013

Flash Flood Warning 10, NWS St. Louis, MO

May 20, 2013Jersey County, Macoupin County, Madison County, Illinois

NWS St. Louis, MO issued this flash flood warning at May 20, 2013, 10:22 PM CDT for Jersey County, Macoupin County, Madison County, Illinois. It was in force for 6 hr. 3 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
May 20, 2013, 10:22 PM CDT (03:22 UTC)
Expired
May 21, 2013, 4:30 AM CDT
In force
6 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Jersey County, IL, Macoupin County, IL, Madison County, IL

The radar

The St Louis radar (KLSX), 61 km from the middle of the area, began a volume at 03:22 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

TimeReportWhereRemark
May 20, 11:51 PM CDTHEAVY RAIN 3.84Plainview, IL
May 21, 12:00 AM CDTHEAVY RAIN 2.821 S Medora, ILRUNNING WATER OVER MANY ROADS INCLUDING IL 16... IL 111... AND IL 267 AS WELL AS COUNTY AND TOWNSHIP ROADS THROUGHOUT FIDELITY...KEMPER... PIASA... SUMMERVILLE AND CHESTERFIELD AREAS
May 21, 1:00 AM CDTHEAVY RAIN 3.57 S Carlinville, IL

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, 3.4 hours before the alert went out and 181 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 00:00Z on 2013-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1540 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 00:00Z on 2013-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 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
1540 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
1320 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
173 m²/s²
Significant tornado parameter
0.8
Supercell composite
6.7

Open this sounding in Storm Lab

The text

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

641 
WGUS53 KLSX 210322
FFWLSX
ILC083-117-119-210930-
/O.NEW.KLSX.FF.W.0010.130521T0322Z-130521T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1022 PM CDT MON MAY 20 2013

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  JERSEY COUNTY IN SOUTHWEST ILLINOIS...
  MACOUPIN COUNTY IN SOUTHWEST ILLINOIS...
  NORTHWESTERN MADISON COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 430 AM CDT TUESDAY

* AT 1020 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE
  WARNED AREA. RADAR ESTIMATES RAINS OF 1 TO 3 INCHES ACROSS THE
  AREA OVER THE LAST SEVERAL HOURS....AND ADDITIONAL MODERATE TO
  HEAVY RAIN CAN BE EXPECTED THROUGH 11 PM.  

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  ALTON...BETHALTO...CARLINVILLE...GILLESPIE...GODFREY...
  JERSEYVILLE...STAUNTON...VIRDEN...WOOD RIVER...BENLD...BRIGHTON...
  BUNKER HILL...DORSEY...ELSAH...GIRARD...GRAFTON...HARTFORD...
  KEMPER...MOUNT OLIVE...PALMYRA...PRAIRIETOWN...ROXANA...SHIPMAN...
  WILSONVILLE AND WORDEN.

A STORM SPOTTER 1 MILE SOUTH OF MEDORA REPORTED 2.4 INCHES SO FAR 
THIS EVENING.

THIS WARNING ALSO INCLUDES...
INTERSTATE 55 IN ILLINOIS FROM EXIT 41 TO EXIT 44.

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 3952 8970 3900 8971 3881 9011 3885 9011
      3891 9022 3897 9042 3897 9048 3895 9052
      3899 9057 3911 9061 3918 9058 3918 9051
      3916 9050 3918 9049 3918 9031 3922 9031
      3923 9020 3925 9020 3926 9015 3952 9015

$$

TRUETT
1 follow-up statement
242 
WGUS73 KLSX 210922
FFSLSX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
422 AM CDT TUE MAY 21 2013

ILC083-117-119-210937-
/O.EXP.KLSX.FF.W.0010.000000T0000Z-130521T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
JERSEY IL-MACOUPIN IL-MADISON IL-
422 AM CDT TUE MAY 21 2013

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR NORTHWESTERN
MADISON...MACOUPIN AND JERSEY COUNTIES WILL BE ALLOWED TO EXPIRE AT
430 AM CDT...

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 3952 8970 3900 8971 3881 9011 3885 9011
      3891 9022 3897 9042 3897 9048 3895 9052
      3899 9057 3911 9061 3918 9058 3918 9051
      3916 9050 3918 9049 3918 9031 3922 9031
      3923 9020 3925 9020 3926 9015 3952 9015

$$

PHILLIPSON

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 7:27 PM CDTSevere Thunderstorm WarningLSXAdams, Brown, Pike48 min
May 20, 7:30 PM CDTTornado Warning Tornado observedLSXAdams, Pike30 min
May 20, 9:28 PM CDTSevere Thunderstorm WarningLSXMacoupin, Madison47 min
May 20, 9:36 PM CDTSevere Thunderstorm WarningLSXCalhoun39 min
May 20, 9:39 PM CDTFlash Flood WarningLSXCalhoun6 hr
May 20, 10:10 PM CDTSevere Thunderstorm WarningLSXMadison, Monroe, Saint Clair35 min
May 20, 10:17 PM CDTSevere Thunderstorm WarningLSXMacoupin, Madison, Montgomery43 min
May 20, 10:31 PM CDTSevere Thunderstorm WarningLSXBond, Clinton, Madison, Montgomery, Saint Clair59 min
May 20, 10:38 PM CDTSevere Thunderstorm WarningLSXMonroe, Randolph67 min
May 20, 11:29 PM CDTRiver Flood WarningLSXMadison3 days

Nearby

Flash Flood Warnings in Illinois, 2013Every flash flood warning in 2013

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.