Alert archive / Illinois / Tornado Warnings in 2021

Tornado Warning 25, NWS Quad Cities, IA

August 25, 2021Henry County, Illinois

NWS Quad Cities, IA issued this tornado warning at Aug 25, 2021, 3:43 PM CDT for Henry County, Illinois. It was in force for 17 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: Aug 25, 2021, 3:43 PM CDT (20:43 UTC)
Expired: Aug 25, 2021, 4:00 PM CDT
In force: 17 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Tornado: Observed
Hail: 0.0 in

County Henry County, IL

The radar

The Quad Cities radar (KDVN), 38 km from the middle of the area, began a volume at 20:46 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 12:00Z, 8.7 hours before the alert went out and 33 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: 818 J/kg
Mixed-layer CIN: -238 J/kg
Mixed-layer LCL: 1355 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -32 m²/s²
0-3 km storm-relative helicity: -10 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted.

764 
WFUS53 KDVN 252043
TORDVN
ILC073-252100-
/O.NEW.KDVN.TO.W.0025.210825T2043Z-210825T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Quad Cities IA/IL
343 PM CDT Wed Aug 25 2021

The National Weather Service in the Quad Cities has issued a

* Tornado Warning for...
  Central Henry County in northwestern Illinois...

* Until 400 PM CDT.

* At 343 PM CDT, a confirmed tornado was located near Geneseo, or 7
  miles north of Cambridge, moving east at 20 mph.

  HAZARD...Damaging tornado.

  SOURCE...Law enforcement confirmed tornado.

  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.

* The tornado will be near...
  Geneseo around 350 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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.

&&

LAT...LON 4140 9033 4147 9028 4144 9005 4130 9014
TIME...MOT...LOC 2043Z 292DEG 17KT 4140 9024 

TORNADO...OBSERVED
MAX HAIL SIZE...0.00 IN

$$

Gibbs

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 24, 7:22 PM CDT	Special Weather Statement	DVN	Henry	53 min
Aug 25, 3:37 PM CDT	Special Weather Statement	DVN	Henry	53 min
Aug 25, 3:39 PM CDT	Severe Thunderstorm Warning	DVN	Henry	36 min
Aug 25, 4:11 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DVN	Henry	49 min
Aug 25, 4:46 PM CDT	Severe Thunderstorm Warning	DVN	Bureau	29 min
Aug 25, 4:59 PM CDT	Severe Thunderstorm Warning	DVN	Bureau, Putnam	46 min
Aug 25, 6:12 PM CDT	Special Weather Statement	DVN	McDonough	33 min

Nearby

Tornado Warnings in Illinois, 2021 Every tornado warning in 2021 Tornadoes 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.