Alert archive / Illinois / Flash Flood Warnings in 2003

Flash Flood Warning 2, NWS Quad Cities, IA

April 30, 2003Henry County, Illinois

NWS Quad Cities, IA issued this flash flood warning at Apr 30, 2003, 9:24 PM CDT for Henry County, Illinois. It was in force for 5 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 30, 2003, 9:24 PM CDT (02:24 UTC)
Expired
May 1, 2003, 2:15 AM CDT
In force
5 hr
Issued by
NWS Quad Cities, IA
Area
Counties, with a storm outline in the text

County Henry County, IL

The radar

The Quad Cities radar (KDVN), 50 km from the middle of the area, began a volume at 02:28 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

Davenport, (KDVN), launched 00:00Z, 2.4 hours before the alert went out and 45 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, Davenport, at 00:00Z on 2003-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1022 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, Davenport, at 00:00Z on 2003-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 457 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
1022 J/kg
Mixed-layer CIN
-104 J/kg
Mixed-layer LCL
839 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
457 m²/s²
0-3 km storm-relative helicity
611 m²/s²
Significant tornado parameter
0.0
Supercell composite
12.6

Open this sounding in Storm Lab

The text

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

000 
WGUS53 KDVN 010224
FFWDVN
ILC073-010715-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
924 PM CDT WED APR 30 2003

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  HENRY COUNTY IN NORTHWEST ILLINOIS

* UNTIL 215 AM CDT

* AT 915 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAIN WERE OVER WESTERN HENRY COUNTY
  MOVING EAST AT 40 MPH.  THUNDERSTORMS OVER THE SOUTHERN HALF OF 
  THE COUNTY HAVE BEEN MOVING OVER THE SAME AREA REPEATEDLY OVER
  THE LAST HOUR. 

* NATIONAL WEATHER SERVICE DOPPLER RADAR ESTIMATES INDICATE THAT UP
  TO 4 TO 6 INCHES OF RAIN HAS FALLEN FROM THE CAMBRIDGE AREA WEST
  THROUGH OPHEIM SINCE 7 PM.  JUST SOUTH OF THIS AREA RADAR ESTIMATED
  A LARGE AREA OF 2 TO 3 INCHES OF RAIN. HEAVY RAIN PRODUCING THUNDERSTORMS
  WILL CONTINUE TO MOVE ACROSS THE SOUTHERN HALF OF THE COUNTY UNTIL AT
  LEAST 1030 PM AND COULD PRODUCE ANOTHER 2 INCHES OF RAIN. THE HENRY
  COUNTY SHERIFF HAS ALREADY REPORTED CONSIDERABLE FLOODING OF LOW LYING 
  AREAS...CITY STREETS AND SMALL CREEKS.  THE  ADDITIONAL RAINS WILL 
  ADD TO THE ONGOING FLOODING.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS AND STREAMS AND OTHER
LOW LYING AREAS ARE SUBJECT TO FLASH FLOODING.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED...
QUICKLY MOVE TO HIGHER GROUND TO ESCAPE FLOOD WATERS.

DO NOT DRIVE YOUR VEHICLE INTO WATER COVERED ROADWAYS. THE WATER MAY
BE TOO DEEP TO CROSS SAFELY OR THE ROAD COULD BE WASHED OUT. VEHICLES
CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.

LAT...LON 4148 8987 4116 8987 4115 9045 4147 9043

$$

DLF
2 follow-up statements
000 
WGUS73 KDVN 010421
FFSDVN
ILC073-010715-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1122 PM CDT WED APR 30 2003

...A FLASH FLOOD WARNING CONTINUES UNTIL 215 AM CDT FOR HENRY 
   COUNTY ILLINOIS...

AT 1102 PM CDT...THE HEAVY RAIN PRODUCING THUNDERSTORMS HAVE
MOVED OUT OF THE AREA.  HOWEVER...RADAR INDICATED SCATTERED THUNDERSTORMS
OVER MERCER AND ROCK ISLAND COUNTIES MOVING EAST AT 40 MPH.  THESE STORMS
WILL MOVE OVER HENRY COUNTY BY 1230 AM AND COULD PRODUCE ANOTHER ONE HALF
INCH OF RAIN IN A FEW LOCATIONS.

RADAR RAINFALL ESTIMATES SHOWED AN AREA OF 3 TO 6 INCHES OF RAIN OVER
SOUTHERN HENRY COUNTY THROUGH WOODHULL...BISHOP HILL AND GALVA. AT 
10 PM CDT A SPOTTER REPORTED 6 INCHES OF RAIN HAD FALLEN IN 3 HOURS NEAR
NEW WINDSOR IN EXTREME SOUTHWEST HENRY COUNTY.  

EVEN THROUGH MOST OF THE HEAVY RAIN HAS ENDED...SCATTERED THUNDERSTORMS
THROUGH 2 AM AND EXCESSIVE RUNOFF FROM EARLIER RAINS WILL AGGRAVATE 
ONGOING FLOODING.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED...
QUICKLY MOVE TO HIGHER GROUND TO ESCAPE FLOOD WATERS.

DO NOT DRIVE YOUR VEHICLE INTO WATER COVERED ROADWAYS. THE WATER MAY
BE TOO DEEP TO CROSS SAFELY OR THE ROAD COULD BE WASHED OUT. VEHICLES
CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.

$$

DLF
000 
WGUS73 KDVN 010725
FFSDVN
ILC073-010740-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
218 AM CDT THU MAY 1 2003

...THE FLASH FLOOD WARNING WHICH WAS IN EFFECT UNTIL 215 AM CDT FOR 
HENRY COUNTY ILLINOIS...HAS BEEN ALLOWED TO EXPIRE...

AT 212 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT THE HEAVY RAINFALL HAS SUBSIDED OVER THE WARNED AREA.  
ADDITIONAL RAIN WITH SOME EMBEDDED THUNDERSTORMS WILL CONTINUE IN 
HENRY COUNTY THROUGH AT LEAST 4 AM...BUT AGAIN THE HEAVY RAIN THREAT 
HAS SHIFTED EAST AND SOUTH OF THE AREA.  PEOPLE WITH INTERESTS ALONG 
SPRING CREEK AND THE EDWARDS RIVER SHOULD STILL MONITOR THOSE AREAS 
FOR HIGH WATER...BUT OTHER STREAMS AND CREEKS HAVE RECEDED OR WERE 
BEGINNING TO RECEDE. EVEN THOUGH STREAMS AND CREEKS WERE RECEDING... 
SOME ROADWAYS MAY STILL BE COVERED WITH WATER. MOTORISTS ARE ADVISED 
TO AVOID DRIVING THROUGH FLOODED ROADWAYS. 

HENRY COUNTY OFFICIALS REPORTED THAT THE MAJOR STREET FLOODING HAS 
SUBSIDED. BUT NUISANCE FLOODING AND OTHER MINOR FLOODING PROBLEMS... 
WILL LAST INTO THURSDAY MORNING IN MUCH OF HENRY COUNTY.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED...
QUICKLY MOVE TO HIGHER GROUND TO ESCAPE FLOOD WATERS.

$$

12

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 30, 7:20 PM CDTTornado WarningDVNHenry55 min
Apr 30, 8:00 PM CDTFlash Flood WarningDVNMercer5 hr
Apr 30, 8:22 PM CDTTornado WarningDVNHenry38 min
Apr 30, 8:25 PM CDTSevere Thunderstorm WarningDVNRock Island50 min
Apr 30, 8:36 PM CDTSevere Thunderstorm WarningDVNMercer39 min
Apr 30, 8:44 PM CDTTornado WarningDVNBureau61 min
Apr 30, 8:55 PM CDTTornado WarningDVNBureau50 min
Apr 30, 9:02 PM CDTSevere Thunderstorm WarningDVNHenry58 min
Apr 30, 9:37 PM CDTTornado WarningDVNPutnam38 min
Apr 30, 9:42 PM CDTSevere Thunderstorm WarningDVNHenderson48 min
Apr 30, 9:48 PM CDTTornado WarningDVNBureau57 min
Apr 30, 10:02 PM CDTSevere Thunderstorm WarningDVNWarren43 min
Apr 30, 10:15 PM CDTTornado WarningDVNPutnam45 min

Nearby

Flash Flood Warnings in Illinois, 2003Every flash flood warning in 2003

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.