Alert archive / Illinois / Tornado Warnings in 2021

Tornado Warning 20, NWS Quad Cities, IA

August 9, 2021Bureau County, Illinois

NWS Quad Cities, IA issued this tornado warning at Aug 9, 2021, 6:50 PM CDT for Bureau County, Illinois. It was in force for 25 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
Aug 9, 2021, 6:50 PM CDT (23:50 UTC)
Expired
Aug 9, 2021, 7:15 PM CDT
In force
25 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.0 in

County Bureau County, IL

The radar

The Chicago radar (KLOT), 103 km from the middle of the area, began a volume at 23:52 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
Aug 9, 6:57 PM CDTTORNADO1 Ne Zearing, ILEF1 TORNADO BEGAN IN A CORN FIELD CAUSING DAMAGE TO CROPS. AS IT MOVED TO THE EAST THE TORNADO CAUSED DAMAGE TO FOUR FARMSTEADS. EF1 DAMAGE WAS FOUND AT THE FIRST AND SECOND FARMSTEAD WHERE TREES WERE SNAPPED AND THREE SHEDS WERE COMPLETELY DESTROYED. ANOTHER
Aug 9, 7:09 PM CDTTORNADO1 W Arlington, ILRAIN WRAPPED TORNADO.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 9, 2:43 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.8 hours before the alert went out and 101 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 12:00Z on 2021-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1676 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 12:00Z on 2021-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 171 square meters per square second.193958Sfc1 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
1676 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
705 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
171 m²/s²
0-3 km storm-relative helicity
208 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted.

661 
WFUS53 KDVN 092350
TORDVN
ILC011-100015-
/O.NEW.KDVN.TO.W.0020.210809T2350Z-210810T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
650 PM CDT Mon Aug 9 2021

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Northeastern Bureau County in north central Illinois...

* Until 715 PM CDT.
    
* At 650 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near La Moille, or 10 miles northeast of Princeton,
  moving east at 30 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This tornadic thunderstorm will remain over mainly rural areas of
  northeastern Bureau County, including the following locations...
  Cherry, Zearing and Arlington.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4145 8940 4153 8939 4154 8917 4139 8917
TIME...MOT...LOC 2350Z 279DEG 25KT 4148 8931 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

Gibbs
1 follow-up statement
904 
WWUS53 KDVN 100001
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
701 PM CDT Mon Aug 9 2021

ILC011-100015-
/O.CON.KDVN.TO.W.0020.000000T0000Z-210810T0015Z/
Bureau IL-
701 PM CDT Mon Aug 9 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 715 PM CDT FOR
NORTHEASTERN BUREAU COUNTY...
    
At 701 PM CDT, a severe thunderstorm capable of producing a tornado
was located near La Moille, or 9 miles southwest of Mendota, moving
east at 15 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Arlington.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4147 8935 4150 8935 4152 8917 4143 8917
TIME...MOT...LOC 0001Z 275DEG 13KT 4148 8928 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

Gibbs

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 4:59 AM CDTSpecial Weather StatementDVNStephenson31 min
Aug 9, 7:08 AM CDTSpecial Weather StatementDVNStephenson22 min
Aug 9, 7:38 AM CDTSpecial Weather StatementDVNStephenson22 min
Aug 9, 5:55 PM CDTTornado WarningDVNBureau50 min

Nearby

Tornado Warnings in Illinois, 2021Every tornado warning in 2021Tornadoes 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.