Alert archive / Illinois / Severe Thunderstorm Watches in 2000

Severe Thunderstorm Watch 663

August 9, 200012 counties in Illinois; 10 counties in Indiana

The Storm Prediction Center issued this severe thunderstorm watch at Aug 9, 2000, 5:00 AM CDT for 12 counties in Illinois; 10 counties in Indiana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Aug 9, 2000, 5:00 AM CDT (10:00 UTC)
Expired: Aug 9, 2000, 10:00 AM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 22 counties

Champaign County, IL, DeWitt County, IL, Ford County, IL, Iroquois County, IL, Kankakee County, IL, LaSalle County, IL, Livingston County, IL, McLean County, IL, Piatt County, IL, Putnam County, IL, Vermilion County, IL, Woodford County, IL, Benton County, IN, Fountain County, IN, Jasper County, IN, Montgomery County, IN, Newton County, IN, Parke County, IN, Tippecanoe County, IN, Vermillion County, IN, Warren County, IN, White County, IN

The radar

The Chicago radar (KLOT), 99 km from the middle of the area, began a volume at 09:59 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.

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Aug 9, 6:27 AM CDT	Severe Thunderstorm Warning	IWX	White	23 min

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 10.0 hours before the alert went out and 71 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: 1188 J/kg
Mixed-layer CIN: -210 J/kg
Mixed-layer LCL: 1135 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 100 m²/s²
0-3 km storm-relative helicity: 251 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

378 
WWUS9 KMKC 090949
SEL3  

SEL3  
MKC WW 090944
ILZ000-INZ000-091500-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 663
STORM PREDICTION CENTER NORMAN OK
444 AM CDT WED AUG 9 2000

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   EASTCENTRAL ILLINOIS                           
   WESTCENTRAL INDIANA                            

EFFECTIVE THIS WEDNESDAY MORNING FROM 500 AM UNTIL 1000 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 45 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 30 MILES NORTHWEST OF BLOOMINGTON
ILLINOIS TO 20 MILES EAST SOUTHEAST OF LAFAYETTE INDIANA.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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 662...

DISCUSSION...SEVERE THUNDERSTORMS MOVING ACROSS CENTRAL IL ALONG
AXIS OF STRONG INSTABILITY AND IN AREA OF FAVORABLE DEEP LAYER
SHEAR.  STORMS EXPECTED TO CONTINUE THREAT OF WIND
DAMAGE...PARTICULARLY IN STORMS THAT TAKE ON BOW CONFIGURATION.


AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600.  MEAN STORM
MOTION VECTOR 29035.


...HALES

412,0891 405,0863 393,0863 400,0891

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 9, 1:00 AM CDT	Severe Thunderstorm Watch	SPC	Bureau, Fulton, Hancock, Henderson, Henry, Knox and 10 more	5 hr
Aug 9, 7:00 AM CDT	Severe Thunderstorm Watch	SPC	Blackford, Boone, Carroll, Cass, Clinton, Delaware and 18 more	5 hr
Aug 9, 3:15 PM CDT	Severe Thunderstorm Watch	SPC	Bartholomew, Blackford, Boone, Brown, Clay, Clinton and 37 more	6 hr
Aug 9, 6:00 PM CDT	Severe Thunderstorm Watch	SPC	Ohio, Switzerland	6 hr

Nearby

Severe Thunderstorm Watches in Illinois, 2000 Severe Thunderstorm Watches in Indiana, 2000 Every severe thunderstorm watch in 2000

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.