Alert archive / Illinois / Severe Thunderstorm Warnings in 2005

Severe Thunderstorm Warning 21, NWS Quad Cities, IA

April 20, 2005Henderson County, Illinois; Des Moines County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Apr 20, 2005, 7:01 PM CDT for Henderson County, Illinois; Des Moines County, Iowa. It was in force for 60 min. 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 20, 2005, 7:01 PM CDT (00:01 UTC)
Expired
Apr 20, 2005, 8:01 PM CDT
In force
60 min
Issued by
NWS Quad Cities, IA
Area
Counties, with a storm outline in the text

Counties Des Moines County, IA, Henderson County, IL

The radar

The Quad Cities radar (KDVN), 78 km from the middle of the area, began a volume at 00:00 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, 0.0 hours before the alert went out and 82 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 2005-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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 2005-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 122 square meters per square second.1939Sfc1 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
5 J/kg
Mixed-layer CIN
-210 J/kg
Mixed-layer LCL
656 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
122 m²/s²
0-3 km storm-relative helicity
233 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.

000 
WUUS53 KDVN 210001
SVRDVN
IAC057-ILC071-210100-
/O.NEW.KDVN.SV.W.0021.050421T0001Z-050421T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
701 PM CDT WED APR 20 2005

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN DES MOINES COUNTY IN SOUTHEAST IOWA
  HENDERSON COUNTY IN WEST CENTRAL ILLINOIS
  THIS INCLUDES THE CITY OF OQUAWKA

* UNTIL 800 PM CDT

* AT 658 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 9 MILES
  NORTH OF OQUAWKA...AND MOVING SOUTH AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  OQUAWKA AND ROZETTA BY 720 PM CDT
  GLADSTONE AND 6 MILES WEST OF BIGGSVILLE BY 735 PM CDT

THIS IS A DANGEROUS STORM. MOVE IMMEDIATELY INDOORS AND STAY AWAY
FROM WINDOWS.

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE
WARNING.

THIS STORM IS ALSO PRODUCING HEAVY RAIN AND URBAN AND SMALL STREAM
FLOODING.

LAT...LON 4107 9085 4107 9099 4081 9115 4078 9085

$$

MCCLURE
4 follow-up statements
000 
WWUS53 KDVN 210013
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
711 PM CDT WED APR 20 2005

IAC057-ILC071-210100-
/O.CON.KDVN.SV.W.0021.000000T0000Z-050421T0100Z/
DES MOINES IA-HENDERSON IL-
711 PM CDT WED APR 20 2005

...A SEVERE THUNDERSTORM WARNING CONTINUES UNTIL 800 PM CDT FOR
NORTHERN HENDERSON AND NORTHEASTERN DES MOINES COUNTIES...

AT 710 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A   
SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL NEAR 
BIG RIVER STATE FOREST...OR ABOUT 7 MILES NORTH OF OQUAWKA...MOVING 
SOUTH AT 15 MPH. AT 658 PM CDT...A TRAINED SPOTTER REPORTED QUARTER 
SIZE HAIL IN KEITHSBURG. 

THE SEVERE THUNDERSTORM WILL BE NEAR...
  BIG RIVER STATE FOREST NOW
  BALD BLUFF BY 720 PM CDT
  DELABAR STATE PARK BY 725 PM CDT
  ROZETTA AND OQUAWKA BY 730 PM CDT
  GLADSTONE BY 745 PM CDT
  BIGGSVILLE BY 755 PM CDT

THIS IS A DANGEROUS STORM. MOVE IMMEDIATELY INDOORS AND STAY AWAY
FROM WINDOWS.

THIS STORM IS ALSO PRODUCING HEAVY RAIN AND URBAN AND SMALL STREAM
FLOODING.

LAT...LON 4107 9085 4107 9099 4082 9112 4078 9085

$$

MCCLURE
000 
WWUS53 KDVN 210015 CCA
SVSDVN

SEVERE WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
711 PM CDT WED APR 20 2005

IAC057-ILC071-210100-
/O.CON.KDVN.SV.W.0021.000000T0000Z-050421T0100Z/
DES MOINES IA-HENDERSON IL-
711 PM CDT WED APR 20 2005

...A SEVERE THUNDERSTORM WARNING CONTINUES UNTIL 800 PM CDT FOR  
HENDERSON AND EASTERN DES MOINES COUNTIES...

AT 710 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A   
SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL NEAR 
BIG RIVER STATE FOREST...OR ABOUT 7 MILES NORTH OF OQUAWKA...MOVING 
SOUTH AT 15 MPH. AT 658 PM CDT...A TRAINED SPOTTER REPORTED QUARTER 
SIZE HAIL IN KEITHSBURG. 

THE SEVERE THUNDERSTORM WILL BE NEAR...
  BIG RIVER STATE FOREST NOW
  BALD BLUFF BY 720 PM CDT
  DELABAR STATE PARK BY 725 PM CDT
  ROZETTA AND OQUAWKA BY 730 PM CDT
  GLADSTONE BY 745 PM CDT
  BIGGSVILLE BY 755 PM CDT

THIS IS A DANGEROUS STORM. MOVE IMMEDIATELY INDOORS AND STAY AWAY
FROM WINDOWS.

THIS STORM IS ALSO PRODUCING HEAVY RAIN AND URBAN AND SMALL STREAM
FLOODING.

LAT...LON 4107 9085 4107 9099 4082 9112 4078 9085

$$

MCCLURE
000 
WWUS53 KDVN 210024
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
723 PM CDT WED APR 20 2005

IAC057-210031-
/O.CAN.KDVN.SV.W.0021.000000T0000Z-050421T0100Z/
DES MOINES IA-
723 PM CDT WED APR 20 2005

...THE SEVERE THUNDERSTORM WARNING FOR DES MOINES COUNTY IS
CANCELLED...

THE THUNDERSTORM WHICH HAS PRODUCED LARGE HAIL HAS MOVED INTO
HENDERSON COUNTY AND NO LONGER POSES A THREAT TO DES MOINES COUNTY. 
THEREFORE THE SEVERE THUNDERSTORM WARNING HAS BEEN CANCELLED.

LAT...LON 4107 9085 4106 9093 4082 9099 4079 9083

$$

ILC071-210100-
/O.CON.KDVN.SV.W.0021.000000T0000Z-050421T0100Z/
HENDERSON IL-
723 PM CDT WED APR 20 2005

...A SEVERE THUNDERSTORM WARNING CONTINUES UNTIL 800 PM CDT FOR
CENTRAL HENDERSON COUNTY...

AT 721 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A SEVERE THUNDERSTORM WITH A HISTORY OF PRODUCING QUARTER 
SIZE HAIL NEAR BALD BLUFF...OR ABOUT 6 MILES NORTHEAST OF 
OQUAWKA...MOVING SOUTH AT 25 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  ROZETTA AND DELABAR STATE PARK BY 727 PM CDT
  OQUAWKA BY 730 PM CDT
  GLADSTONE BY 740 PM CDT
  BIGGSVILLE BY 745 PM CDT

THIS IS A DANGEROUS STORM. MOVE IMMEDIATELY INDOORS AND STAY AWAY
FROM WINDOWS.

THIS STORM IS ALSO PRODUCING HEAVY RAIN AND URBAN AND SMALL STREAM
FLOODING.

LAT...LON 4107 9085 4106 9093 4082 9099 4079 9083

$$

MCCLURE
000 
WWUS53 KDVN 210101
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
802 PM CDT WED APR 20 2005

ILC071-210112-
/O.EXP.KDVN.SV.W.0021.000000T0000Z-050421T0100Z/
HENDERSON IL-
802 PM CDT WED APR 20 2005

...THE SEVERE THUNDERSTORM WARNING FOR HENDERSON COUNTY EXPIRES AT 
800 PM CDT...

THE THUNDERSTORM THAT WAS CAPABLE OF PRODUCING SEVERE WEATHER HAS
WEAKENED. THEREFORE THE SEVERE THUNDERSTORM WARNING HAS BEEN ALLOWED
TO EXPIRE.

LAT...LON 4107 9085 4106 9093 4082 9099 4079 9083

$$

MCCLURE

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 7:35 PM CDTSevere Thunderstorm WarningDVNWarren42 min
Apr 21, 3:30 PM CDTSevere Thunderstorm WarningDVNHancock30 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2005Severe Thunderstorm Warnings in Iowa, 2005Every severe thunderstorm warning in 2005

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.