Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 113, NWS Chicago, IL

December 10, 2021Ford County, Iroquois County, Livingston County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Dec 10, 2021, 9:27 PM CST for Ford County, Iroquois County, Livingston County, Illinois. It was in force for 48 min. 1 report 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: Dec 10, 2021, 9:27 PM CST (03:27 UTC)
Expired: Dec 10, 2021, 10:15 PM CST
In force: 48 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Ford County, IL, Iroquois County, IL, Livingston County, IL

The radar

The Chicago radar (KLOT), 107 km from the middle of the area, began a volume at 03:28 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.

What was reported inside it

Time	Report	Where	Remark
Dec 10, 9:30 PM CST	TSTM WND DMG	Gibson City, IL	ROOF PARTIALLY BLOWN OFF A RESIDENTIAL BUILDING AND A COUPLE TREES DOWNED.

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.

Issued	Product	Office	Lasted
Dec 10, 7:47 PM CST	Tornado Watch	SPC	8 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 3.5 hours before the alert went out and 66 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: 119 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 662 m above ground
0-6 km bulk shear: 73 kt
0-1 km storm-relative helicity: 341 m²/s²
0-3 km storm-relative helicity: 357 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

840 
WUUS53 KLOT 110327
SVRLOT
ILC053-075-105-110415-
/O.NEW.KLOT.SV.W.0113.211211T0327Z-211211T0415Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Chicago/Romeoville
927 PM CST Fri Dec 10 2021

The National Weather Service in Chicago has issued a

* Severe Thunderstorm Warning for...
  Southeastern Livingston County in central Illinois...
  Ford County in east central Illinois...
  Western Iroquois County in east central Illinois...

* Until 1015 PM CST.

* At 926 PM CST, severe thunderstorms were located along a line
  extending from near Forrest to near Saybrook, moving northeast at
  70 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Paxton, Gibson City, Gilman, Clifton, Chatsworth, Onarga, Forrest,
  Chebanse, Cissna Park, Piper City, Ashkum, Buckley, Crescent City,
  Danforth, Melvin, Loda, Roberts, Elliott, Sibley and Thawville.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 200 AM CST for central and
east central Illinois.

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

&&

LAT...LON 4062 8846 4062 8850 4082 8837 4100 8792
      4100 8786 4049 8785 4049 8794 4040 8793
      4040 8846
TIME...MOT...LOC 0326Z 238DEG 61KT 4072 8838 4040 8860 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Kluber

2 follow-up statements

975 
WWUS53 KLOT 110346
SVSLOT

Severe Weather Statement
National Weather Service Chicago/Romeoville
946 PM CST Fri Dec 10 2021

ILC105-110356-
/O.CAN.KLOT.SV.W.0113.000000T0000Z-211211T0415Z/
Livingston IL-
946 PM CST Fri Dec 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LIVINGSTON COUNTY
IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 200 AM CST for central and
east central Illinois.

LAT...LON 4062 8824 4062 8823 4063 8824 4072 8819
      4090 8807 4100 8792 4100 8786 4049 8785
      4049 8794 4040 8793 4040 8835
TIME...MOT...LOC 0346Z 238DEG 61KT 4089 8803 4057 8825 

$$

ILC053-075-110415-
/O.CON.KLOT.SV.W.0113.000000T0000Z-211211T0415Z/
Ford IL-Iroquois IL-
946 PM CST Fri Dec 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1015 PM CST
FOR SOUTHEASTERN FORD AND WESTERN IROQUOIS COUNTIES...

At 946 PM CST, severe thunderstorms were located along a line
extending from near Ashkum to 10 miles northeast of Gibson City,
moving northeast at 70 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Paxton, Gilman, Clifton, Onarga, Chebanse, Cissna Park, Ashkum,
Buckley, Crescent City, Danforth, Melvin, Loda, Roberts, Elliott,
Thawville and Clarence.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 200 AM CST for central and
east central Illinois.

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

&&

LAT...LON 4062 8824 4062 8823 4063 8824 4072 8819
      4090 8807 4100 8792 4100 8786 4049 8785
      4049 8794 4040 8793 4040 8835
TIME...MOT...LOC 0346Z 238DEG 61KT 4089 8803 4057 8825 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Kluber

034 
WWUS53 KLOT 110406
SVSLOT

Severe Weather Statement
National Weather Service Chicago/Romeoville
1006 PM CST Fri Dec 10 2021

ILC053-075-110416-
/O.EXP.KLOT.SV.W.0113.000000T0000Z-211211T0415Z/
Ford IL-Iroquois IL-
1006 PM CST Fri Dec 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN FORD AND WESTERN
IROQUOIS COUNTIES WILL EXPIRE AT 1015 PM CST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 200 AM CST for central and
east central Illinois.

LAT...LON 4062 8824 4062 8823 4063 8824 4072 8819
      4090 8807 4100 8792 4100 8786 4049 8785
      4049 8794 4040 8793 4040 8835
TIME...MOT...LOC 0406Z 238DEG 61KT 4106 8767 4074 8789 

$$

Kluber

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 10, 9:26 PM CST	Severe Thunderstorm Warning	LOT	Grundy, Will	28 min
Dec 10, 9:46 PM CST	Severe Thunderstorm Warning	LOT	Kankakee, Will	44 min
Dec 10, 9:55 PM CST	Special Weather Statement	LOT	Iroquois	65 min
Dec 10, 10:00 PM CST	Tornado Warning	LOT	Will	16 min
Dec 10, 10:18 PM CST	Special Marine Warning	LOT		27 min
Dec 11, 5:56 PM CST	Small Craft Advisory	LOT		39 hr

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.