Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 106, NWS Quad Cities, IA

September 7, 2021Whiteside County, Illinois

NWS Quad Cities, IA issued this severe thunderstorm warning at Sep 7, 2021, 12:47 PM CDT for Whiteside County, Illinois. It was in force for 29 min. 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: Sep 7, 2021, 12:47 PM CDT (17:47 UTC)
Expired: Sep 7, 2021, 1:16 PM CDT
In force: 29 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Whiteside County, IL

The radar

The Quad Cities radar (KDVN), 65 km from the middle of the area, began a volume at 17:47 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
Sep 7, 12:48 PM CDT	HAIL 0.88	1 W Franklin Corners, IL	DELAYED PUBLIC REPORT. DIME TO NICKEL HAIL. TIME ESTIMATED FROM RADAR.
Sep 7, 12:57 PM CDT	HAIL 0.25	1 S Coleta, IL	DELAYED REPORT AND TIME ESTIMATED FROM RADAR.

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 5.8 hours before the alert went out and 59 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: 827 J/kg
Mixed-layer CIN: -263 J/kg
Mixed-layer LCL: 1475 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 185 m²/s²
0-3 km storm-relative helicity: 167 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

955 
WUUS53 KDVN 071747
SVRDVN
ILC195-071830-
/O.NEW.KDVN.SV.W.0106.210907T1747Z-210907T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
1247 PM CDT Tue Sep 7 2021

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northeastern Whiteside County in northwestern Illinois...

* Until 130 PM CDT.

* At 1246 PM CDT, a severe thunderstorm was located near Fairhaven,
  or near Morrison, moving east at 45 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Coleta around 100 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
sturdy building.

&&

LAT...LON 4188 9005 4193 9005 4190 8963 4182 8963
TIME...MOT...LOC 1746Z 278DEG 40KT 4190 9000 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

08

3 follow-up statements

360 
WWUS53 KDVN 071759
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1259 PM CDT Tue Sep 7 2021

ILC195-071830-
/O.CON.KDVN.SV.W.0106.000000T0000Z-210907T1830Z/
Whiteside IL-
1259 PM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 PM CDT
FOR NORTHEASTERN WHITESIDE COUNTY...

At 1258 PM CDT, a severe thunderstorm was located near Coleta, or 7
miles northeast of Morrison, moving east at 45 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Trained weather spotters.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of
northeastern Whiteside County, including the following locations...
Penrose.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
sturdy building.

&&

LAT...LON 4186 8984 4191 8984 4191 8977 4190 8963
      4182 8963
TIME...MOT...LOC 1758Z 278DEG 40KT 4189 8987 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

08

982 
WWUS53 KDVN 071809
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
109 PM CDT Tue Sep 7 2021

ILC195-071830-
/O.CON.KDVN.SV.W.0106.000000T0000Z-210907T1830Z/
Whiteside IL-
109 PM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 PM CDT
FOR NORTHEASTERN WHITESIDE COUNTY...

At 108 PM CDT, a severe thunderstorm was located near Dixon, moving
east at 50 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of
northeastern Whiteside County, including the following locations...
Penrose.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
sturdy building.

&&

LAT...LON 4185 8971 4190 8971 4191 8977 4190 8963
      4182 8963
TIME...MOT...LOC 1808Z 281DEG 42KT 4187 8960 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

08

634 
WWUS53 KDVN 071816
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
116 PM CDT Tue Sep 7 2021

ILC195-071826-
/O.CAN.KDVN.SV.W.0106.000000T0000Z-210907T1830Z/
Whiteside IL-
116 PM CDT Tue Sep 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN WHITESIDE COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
northwestern Illinois.

LAT...LON 4185 8971 4190 8971 4191 8977 4190 8963
      4182 8963
TIME...MOT...LOC 1815Z 278DEG 40KT 4186 8948 

$$

08

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 12:37 PM CDT	Special Weather Statement	DVN	Carroll	38 min
Sep 7, 2:20 PM CDT	Special Weather Statement	DVN	Bureau	25 min
Sep 7, 2:47 PM CDT	Special Weather Statement	DVN	Putnam	28 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2021 Every severe thunderstorm warning in 2021

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.