Alert archive / Illinois / Tornado Watches in 1997

Tornado Watch 218

April 30, 199726 counties in Illinois; 11 counties in Indiana

The Storm Prediction Center issued this tornado watch at Apr 30, 1997, 2:30 PM CDT for 26 counties in Illinois; 11 counties in Indiana. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Apr 30, 1997, 2:30 PM CDT (19:30 UTC)
Expired: Apr 30, 1997, 9:00 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center

All 37 counties

Bond County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Fayette County, IL, Jasper County, IL, Jefferson County, IL, Lawrence County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Montgomery County, IL, Moultrie County, IL, Richland County, IL, Sangamon County, IL, Shelby County, IL, Washington County, IL, Wayne County, IL, Clay County, IN, Daviess County, IN, Fountain County, IN, Greene County, IN, Knox County, IN, Martin County, IN, Owen County, IN, Parke County, IN, Sullivan County, IN, Vermillion County, IN, Vigo County, IN

The radar

The Lincoln radar (KILX), 107 km from the middle of the area, began a volume at 19:29 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

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

Issued	Product	Office	Counties	Lasted
Apr 30, 2:33 PM CDT	Tornado Warning	LSX	Macoupin	42 min
Apr 30, 2:51 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Fayette	54 min
Apr 30, 2:58 PM CDT	Severe Thunderstorm Warning	LSX	Montgomery	47 min
Apr 30, 3:15 PM CDT	Tornado Warning	ILX	Christian	45 min
Apr 30, 3:29 PM CDT	Severe Thunderstorm Warning	LSX	Washington	46 min
Apr 30, 3:32 PM CDT	Tornado Warning	ILX	Macon	43 min
Apr 30, 3:43 PM CDT	Severe Thunderstorm Warning	LSX	Fayette	32 min
Apr 30, 4:19 PM CDT	Severe Thunderstorm Warning	PAH	Jefferson, Wayne	41 min
Apr 30, 4:30 PM CDT	Severe Thunderstorm Warning	ILX	Coles, Cumberland	30 min
Apr 30, 4:40 PM CDT	Severe Thunderstorm Warning	ILX	Clark, Edgar	50 min
Apr 30, 5:04 PM CDT	Tornado Warning	IND	Parke, Vermillion	26 min
Apr 30, 5:36 PM CDT	Severe Thunderstorm Warning	ILX	Lawrence, Richland	29 min
Apr 30, 5:52 PM CDT	Severe Thunderstorm Warning	IND	Knox	38 min
Apr 30, 6:06 PM CDT	Severe Thunderstorm Warning	IND	Daviess	39 min
Apr 30, 6:24 PM CDT	Severe Thunderstorm Warning	IND	Greene	36 min
Apr 30, 6:43 PM CDT	Severe Thunderstorm Warning	IND	Daviess, Knox	32 min
Apr 30, 7:16 PM CDT	Severe Thunderstorm Warning	IND	Lawrence, Martin	29 min

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.5 hours before the alert went out and 99 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1130 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 166 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

520 
WWUS9 KMKC 301848
SEL8  
MKC WW 301848
ILZ000-INZ000-010200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 218
STORM PREDICTION CENTER NORMAN OK
148 PM CDT WED APR 30 1997

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

CENTRAL AND SOUTHERN ILLINOIS                           
WESTERN INDIANA                            

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 230 PM UNTIL
900 PM CDT.

TORNADOES...HAIL TO 1 3/4 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS ALONG AND 55 STATUTE MILES EITHER SIDE OF
A LINE FROM ALTON ILLINOIS TO 25 MILES EAST OF TERRE HAUTE INDIANA.


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.

DISCUSSION...BAND OF STRONG THUNDERSTORMS HAS DEVELOPED SOUTHWARD
AHEAD OF COLD FRONTAL BULGE.  THIS ACTIVITY IS EXPECTED TO INTENSFY
AND MOVE RAPIDLY EAST NORTHEASTWARD WITH THE POSSIBLITY SUPERCELLS
AND TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 3/4 INCHES.  EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450.  MEAN STORM MOTION VECTOR 24040.


...JOHNS

394,0901 401,0870 384,0863 380,0894

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 30, 12:30 PM CDT	Tornado Watch	SPC	Adams, Brown, Bureau, Carroll, Cass, DeKalb and 28 more	7 hr
Apr 30, 3:30 PM CDT	Tornado Watch	SPC	Champaign, Cook, DuPage, Ford, Grundy, Iroquois and 8 more	6 hr
Apr 30, 5:30 PM CDT	Tornado Watch	SPC	Clark, Coles, Crawford, Cumberland, Douglas, Edgar and 6 more	6 hr
Apr 30, 6:30 PM CDT	Severe Thunderstorm Watch	SPC	Gallatin, Hardin, Johnson, Massac, Pope, Saline and 1 more	6 hr

Nearby

Tornado Watches in Illinois, 1997 Tornado Watches in Indiana, 1997 Every tornado watch in 1997

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.