Alert archive / Illinois / Tornado Watches in 2003

Tornado Watch 351

May 10, 200317 counties in Illinois; 8 counties in Iowa; 10 counties in Wisconsin

The Storm Prediction Center issued this tornado watch at May 10, 2003, 9:35 PM CDT for 17 counties in Illinois; 8 counties in Iowa; 10 counties in Wisconsin. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 10, 2003, 9:35 PM CDT (02:35 UTC)
Expired
May 11, 2003, 1:00 AM CDT
In force
3 hr
Issued by
the Storm Prediction Center
All 35 counties

Cedar County, IA, Clinton County, IA, Des Moines County, IA, Dubuque County, IA, Jackson County, IA, Jones County, IA, Muscatine County, IA, Scott County, IA, Bureau County, IL, Carroll County, IL, Henderson County, IL, Henry County, IL, Jo Daviess County, IL, Knox County, IL, Lee County, IL, Marshall County, IL, Mercer County, IL, Ogle County, IL, Peoria County, IL, Rock Island County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Warren County, IL, Whiteside County, IL, Columbia County, WI, Crawford County, WI, Dane County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Lafayette County, WI, Richland County, WI, Sauk County, WI, Vernon County, WI

The radar

The Quad Cities radar (KDVN), 25 km from the middle of the area, began a volume at 02:36 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

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

IssuedProductOfficeCountiesLasted
May 10, 9:35 PM CDTTornado WarningMKXColumbia, Dane55 min
May 10, 9:36 PM CDTTornado WarningLOTLee39 min
May 10, 9:37 PM CDTSevere Thunderstorm WarningARXRichland53 min
May 10, 9:45 PM CDTTornado WarningILXMason, Tazewell60 min
May 10, 10:09 PM CDTFlash Flood WarningARXGrant3 hr
May 10, 10:36 PM CDTFlash Flood WarningARXRichland2 hr
May 10, 10:43 PM CDTTornado WarningILXMarshall47 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

Davenport, (KDVN), launched 00:00Z, 2.6 hours before the alert went out and 21 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, Davenport, at 00:00Z on 2003-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1566 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2003-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 234 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
1566 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
910 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
234 m²/s²
0-3 km storm-relative helicity
259 m²/s²
Significant tornado parameter
2.8
Supercell composite
12.7

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 110232
SEL1  
SPC WW 110235
IAZ000-ILZ000-WIZ000-110600-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 351 
NWS STORM PREDICTION CENTER NORMAN OK 
935 PM CDT SAT MAY 10 2003

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

       EASTERN IOWA
       WESTERN ILLINOIS
       SOUTHWEST WISCONSIN

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 935 PM UNTIL
100 AM CDT.

...THIS IS A PARTICULARLY DANGEROUS SITUATION...

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

THE TORNADO WATCH AREA IS ALONG AND 50 STATUTE MILES EAST AND WEST
OF A LINE FROM 35 MILES WEST SOUTHWEST OF PEORIA ILLINOIS TO 40
MILES NORTH OF LONEROCK WISCONSIN.

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...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 341...TORNADO WATCH NUMBER 346. WATCH NUMBER 341 346
WILL NOT BE IN EFFECT AFTER 935 PM CDT. CONTINUE...WW 341...WW
346...WW 347...WW 348...WW 349...WW 350...


DISCUSSION...INTENSE TORNADIC SUPERCELLS CONTINUE TO TRACK NEWD
AHEAD OF DEEPENING SURFACE LOW.  CONDITIONS WILL REMAIN FAVORABLE
FOR POTENTIALLY STRONG TORNADOES NEXT SEVERAL HOURS

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 24045.


...HALES

402,0911 434,0911 434,0891 402,0891

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 7:06 PM CDTMesoscale DiscussionSPCAlexander, Franklin, Hardin, Jackson, Johnson, Massac and 7 more54 min
May 10, 8:05 PM CDTTornado WatchSPCBoone, Cook, DeKalb, DuPage, Ford, Grundy and 12 more6 hr
May 10, 8:18 PM CDTMesoscale DiscussionSPCBureau, Carroll, Henderson, Henry, Jo Daviess, Knox and 8 more117 min
May 10, 8:41 PM CDTMesoscale DiscussionSPCCrawford, Lawrence, Richland, Wabash2 hr
May 10, 8:45 PM CDTTornado WatchSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more5 hr
May 10, 9:10 PM CDTTornado WatchSPCAdams, Bond, Brown, Calhoun, Cass, Champaign and 45 more5 hr
May 10, 10:56 PM CDTMesoscale DiscussionSPCBoone, Bureau, Cook, DeKalb, DuPage, Ford and 19 more94 min
May 11, 1:46 AM CDTMesoscale DiscussionSPCAdams, Bond, Brown, Calhoun, Cass, Champaign and 42 more89 min

Nearby

Tornado Watches in Illinois, 2003Tornado Watches in Wisconsin, 2003Tornado Watches in Iowa, 2003Every tornado watch in 2003

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.