Alert archive / Illinois / Tornado Watches in 2021

Tornado Watch 559

December 10, 20214 states

The Storm Prediction Center issued this tornado watch at Dec 10, 2021, 11:03 PM CST for 4 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Dec 10, 2021, 11:03 PM CST (05:03 UTC)
Expired
Dec 11, 2021, 3:48 AM CST
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 56 counties

Alexander County, IL, Clinton County, IL, Edwards County, IL, Fayette County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Johnson County, IL, Marion County, IL, Massac County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Saline County, IL, Union County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Gibson County, IN, Pike County, IN, Posey County, IN, Spencer County, IN, Vanderburgh County, IN, Warrick County, IN, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Daviess County, KY, Fulton County, KY, Graves County, KY, Henderson County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, McLean County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Union County, KY, Webster County, KY, Bollinger County, MO, Cape Girardeau County, MO, Mississippi County, MO, Perry County, MO, Scott County, MO

The radar

The Evansville,IN radar (KVWX), 49 km from the middle of the area, began a volume at 05:02 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
80%
One or more EF2 to EF5 tornadoes
70%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Dec 10, 11:06 PM CSTSevere Thunderstorm WarningPAHBollinger, Cape Girardeau, Perry39 min
Dec 10, 11:10 PM CSTTornado WarningLSXClinton, Marion, Washington50 min
Dec 10, 11:11 PM CSTSevere Thunderstorm WarningPAHCrittenden, Hopkins, Union, Webster36 min
Dec 10, 11:17 PM CSTTornado WarningPAHWebster28 min
Dec 10, 11:33 PM CSTSevere Thunderstorm WarningPAHFranklin, Jackson, Jefferson, Perry, Union, Williamson42 min
Dec 10, 11:37 PM CSTTornado WarningPAHSpencer34 min
Dec 10, 11:40 PM CSTTornado Warning Tornado observedConsiderable damage threatPAHCalloway15 min
Dec 11, 12:03 AM CSTTornado Warning Tornado observedConsiderable damage threatPAHChristian, Trigg42 min
Dec 11, 12:08 AM CSTSevere Thunderstorm WarningPAHFranklin, Hamilton, Jefferson, Saline, Wayne, White and 1 more32 min
Dec 11, 12:29 AM CSTTornado Warning Tornado observedConsiderable damage threatPAHTodd21 min
Dec 11, 1:46 AM CSTFlash Flood WarningPAHCalloway, Christian, Todd, Trigg8 hr
Dec 11, 1:49 AM CSTSevere Thunderstorm WarningPAHChristian, Todd26 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 5.1 hours before the alert went out and 241 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, Lincoln, IL at 00:00Z on 2021-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 119 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, Lincoln, IL at 00:00Z on 2021-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 341 square meters per square second.1939587897Sfc1 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
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.

737 
WWUS20 KWNS 110458
SEL9  
SPC WW 110458
ILZ000-INZ000-KYZ000-MOZ000-111100-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 559
NWS Storm Prediction Center Norman OK
1100 PM CST Fri Dec 10 2021

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southern Illinois
  Southwest Indiana
  Western Kentucky
  Southeast Missouri

* Effective this Friday night and Saturday morning from 1100 PM
  until 500 AM CST.

* Primary threats include...
  Several tornadoes and a couple intense tornadoes likely
  Scattered damaging wind gusts to 70 mph possible

SUMMARY...Near-term tornado threat will be greatest with a
long-track strong to potentially violent tornado in western
Kentucky. A tornado and wind threat should persist with an upstream
line of storms across southern Illinois into southeast Missouri.

The tornado watch area is approximately along and 65 statute miles
east and west of a line from 30 miles northeast of Salem IL to 45
miles southeast of Paducah KY. For a complete depiction of the watch
see the associated watch outline update (WOUS64 KWNS WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 552...WW 553...WW
554...WW 555...WW 556...WW 557...WW 558...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 1 inch. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean
storm motion vector 23040.

...Grams

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 10, 7:02 PM CSTMesoscale DiscussionSPCCalhoun, Greene, Jersey, Macoupin, Madison, Monroe and 4 more58 min
Dec 10, 7:18 PM CSTMesoscale DiscussionSPCChampaign, Christian, Clark, Clay, Coles, Crawford and 18 more87 min
Dec 10, 7:47 PM CSTTornado WatchSPCChampaign, Clark, Clay, Coles, Crawford, Cumberland and 21 more8 hr
Dec 10, 8:53 PM CSTMesoscale DiscussionSPCBond, Champaign, Christian, Clark, Clay, Coles and 21 more97 min
Dec 10, 9:36 PM CSTMesoscale DiscussionSPCClark, Coles, Cumberland, Edgar, Effingham, Shelby54 min
Dec 10, 10:09 PM CSTMesoscale DiscussionSPCMassac96 min
Dec 10, 11:28 PM CSTMesoscale DiscussionSPCAlexander, Clark, Clay, Coles, Crawford, Cumberland and 24 more92 min
Dec 10, 6:21 PM CSTTornado WatchSPCClark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more10 hr
Dec 10, 8:35 PM CSTMesoscale DiscussionSPCHarrison85 min
Dec 10, 10:25 PM CSTMesoscale DiscussionSPCBartholomew, Benton, Blackford, Boone, Brown, Carroll and 50 more95 min
Dec 10, 11:08 PM CSTMesoscale DiscussionSPCDearborn, Decatur, Delaware, Fayette, Franklin, Hamilton and 16 more67 min
Dec 10, 11:20 PM CSTTornado WatchSPCAdams, Allen, Blackford, Carroll, Cass, Dearborn and 27 more6 hr
Dec 11, 1:46 AM CSTMesoscale DiscussionSPCBartholomew, Brown, Daviess, Dearborn, Decatur, Delaware and 21 more59 min
Dec 10, 6:22 PM CSTMesoscale DiscussionSPCFulton, Graves, Hickman53 min
Dec 10, 7:41 PM CSTMesoscale DiscussionSPCFulton64 min
Dec 10, 8:48 PM CSTMesoscale DiscussionSPCCarlisle, Fulton, Graves, Hickman, Lyon, Marshall57 min
Dec 10, 9:48 PM CSTMesoscale DiscussionSPCCaldwell, Graves, Hopkins, Lyon, Marshall57 min
Dec 10, 10:44 PM CSTMesoscale DiscussionSPCCaldwell, Grayson, Hopkins, McLean, Muhlenberg, Ohio61 min
Dec 10, 11:36 PM CSTMesoscale DiscussionSPCCalloway, Christian, Logan, Simpson, Todd, Trigg54 min
Dec 10, 11:53 PM CSTMesoscale DiscussionSPCBreckinridge, Bullitt, Grayson, Hardin, Jefferson, Meade and 3 more67 min
Dec 11, 1:02 AM CSTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bath, Bourbon and 51 more88 min
Dec 11, 1:05 AM CSTMesoscale DiscussionSPCBarren, Butler, Edmonson, Green, Hart, Logan and 2 more55 min
Dec 11, 1:27 AM CSTTornado WatchSPCAdair, Allen, Anderson, Barren, Bath, Bourbon and 51 more7 hr
Dec 11, 2:51 AM CSTMesoscale DiscussionSPCBoyle, Casey, Clark, Estill, Garrard, Jessamine and 4 more54 min
Dec 11, 5:32 AM CSTMesoscale DiscussionSPCBell, Breathitt, Clark, Clay, Estill, Jackson and 18 more88 min
Dec 10, 7:54 PM CSTMesoscale DiscussionSPCChristian, Crawford, Dallas, Dent, Douglas, Greene and 10 more2 hr
Dec 10, 9:40 PM CSTMesoscale DiscussionSPCDunklin, Pemiscot2 hr

Nearby

Tornado Watches in Illinois, 2021Tornado Watches in Kentucky, 2021Tornado Watches in Indiana, 2021Every tornado watch 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.