Alert archive / Iowa / Tornado Watches in 2000

Tornado Watch 302

May 18, 200032 counties in Illinois; 36 counties in Iowa; Clark County, Schuyler County, Scotland County, Missouri

The Storm Prediction Center issued this tornado watch at May 18, 2000, 11:30 AM CDT for 32 counties in Illinois; 36 counties in Iowa; Clark County, Schuyler County, Scotland County, Missouri. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 18, 2000, 11:30 AM CDT (16:30 UTC)
Expired
May 18, 2000, 5:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 71 counties

Appanoose County, IA, Benton County, IA, Boone County, IA, Cedar County, IA, Clarke County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Des Moines County, IA, Henry County, IA, Iowa County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Keokuk County, IA, Lee County, IA, Louisa County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Muscatine County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Scott County, IA, Story County, IA, Tama County, IA, Union County, IA, Van Buren County, IA, Wapello County, IA, Warren County, IA, Washington County, IA, Wayne County, IA, Bureau County, IL, Champaign County, IL, DeWitt County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, LaSalle County, IL, Livingston County, IL, Logan County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Mercer County, IL, Peoria County, IL, Piatt County, IL, Putnam County, IL, Rock Island County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Woodford County, IL, Clark County, MO, Schuyler County, MO, Scotland County, MO

The radar

The Quad Cities radar (KDVN), 94 km from the middle of the area, began a volume at 16:31 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

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

IssuedProductOfficeCountiesLasted
May 18, 11:35 AM CDTSevere Thunderstorm WarningILXChampaign40 min
May 18, 11:48 AM CDTSevere Thunderstorm WarningDVNIowa, Johnson42 min
May 18, 11:51 AM CDTTornado WarningDMXPolk, Warren29 min
May 18, 11:55 AM CDTSevere Thunderstorm WarningDVNJefferson, Keokuk50 min
May 18, 11:56 AM CDTSevere Thunderstorm WarningILXVermilion49 min
May 18, 12:07 PM CDTTornado WarningDMXJasper, Marion28 min
May 18, 12:27 PM CDTSevere Thunderstorm WarningDVNCedar, Johnson, Linn48 min
May 18, 12:30 PM CDTSevere Thunderstorm WarningDVNJohnson, Washington45 min
May 18, 12:35 PM CDTTornado WarningDVNWashington25 min
May 18, 12:36 PM CDTSevere Thunderstorm WarningDMXJasper29 min
May 18, 12:43 PM CDTSevere Thunderstorm WarningDVNWhiteside47 min
May 18, 12:44 PM CDTSevere Thunderstorm WarningDVNJefferson, Keokuk46 min
May 18, 12:44 PM CDTSevere Thunderstorm WarningDVNIowa, Johnson46 min
May 18, 12:48 PM CDTSevere Thunderstorm WarningDMXPoweshiek32 min
May 18, 1:01 PM CDTSevere Thunderstorm WarningDVNJohnson, Louisa, Washington44 min
May 18, 1:15 PM CDTSevere Thunderstorm WarningDVNCedar, Johnson, Muscatine30 min
May 18, 1:32 PM CDTTornado WarningDVNMuscatine28 min
May 18, 1:46 PM CDTSevere Thunderstorm WarningDVNCedar29 min
May 18, 1:46 PM CDTSevere Thunderstorm WarningDVNLouisa29 min
May 18, 1:53 PM CDTSevere Thunderstorm WarningDVNCedar, Scott52 min
May 18, 1:59 PM CDTSevere Thunderstorm WarningDVNMuscatine46 min
May 18, 2:21 PM CDTTornado WarningDVNIowa24 min
May 18, 2:29 PM CDTSevere Thunderstorm WarningDVNHenry, Rock Island46 min
May 18, 3:14 PM CDTSevere Thunderstorm WarningDVNHenry31 min
May 18, 3:14 PM CDTTornado WarningDVNHenry31 min
May 18, 3:21 PM CDTTornado WarningDVNBureau24 min
May 18, 3:28 PM CDTSevere Thunderstorm WarningDVNWhiteside47 min
May 18, 3:43 PM CDTTornado WarningDVNBureau47 min
May 18, 3:47 PM CDTTornado WarningDVNHenry28 min
May 18, 4:00 PM CDTSevere Thunderstorm WarningILXPeoria, Stark45 min
May 18, 4:18 PM CDTSevere Thunderstorm WarningILXMarshall42 min
May 18, 4:23 PM CDTSevere Thunderstorm WarningLOTLaSalle67 min
May 18, 4:38 PM CDTTornado WarningILXMarshall37 min
May 18, 4:41 PM CDTTornado WarningDVNPutnam34 min
May 18, 4:46 PM CDTSevere Thunderstorm WarningILXPeoria44 min
May 18, 4:58 PM CDTSevere Thunderstorm WarningILXWoodford47 min
May 18, 5:00 PM CDTSevere Thunderstorm WarningLOTKendall60 min

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 4.5 hours before the alert went out and 101 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 12:00Z on 2000-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1779 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 12:00Z on 2000-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 178 square meters per square second.1939587897117Sfc1 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
1779 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
796 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
178 m²/s²
0-3 km storm-relative helicity
310 m²/s²
Significant tornado parameter
2.4
Supercell composite
10.8

Open this sounding in Storm Lab

The text

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

423 
WWUS9 KMKC 181553
SEL2  

SEL2  
MKC WW 181553
IAZ000-ILZ000-182200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 302
STORM PREDICTION CENTER NORMAN OK
1053 AM CDT THU MAY 18 2000

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

   SOUTHERN IOWA                               
   NORTHERN AND CENTRAL ILLINOIS                           

EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 1130 AM UNTIL
500 PM CDT.

TORNADOES...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 60 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 35 MILES WEST OF DES MOINES IOWA TO 30 MILES
NORTH OF DANVILLE ILLINOIS.

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 301...

DISCUSSION...RAPID DEVELOPMENT OF SEVERE THUNDERSTORMS OCCURING SRN
IA AHEAD OF SURFACE/UPPER LOW.  AIRMASS VERY UNSTABLE EWD ACROSS
SERN IA INTO IL WITH CAPES AOA 3000 J/KG.  E/W BOUNDARY ACROSS NRN
IL INTO IA WILL ENHANCE LOW LEVEL SHEAR PROFILES SUPPORTING
TORNADIC SUPERCELLS AS STORMS DEVELOP EWD FROM SRN IA.


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 25040.


...HALES

422,0942 413,0873 394,0873 403,0942

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 18, 3:00 PM CDTTornado WatchSPCAdams, Brown, Bureau, Calhoun, Cass, Christian and 39 more6 hr
May 18, 6:00 PM CDTTornado WatchSPCBond, Champaign, Christian, Clark, Clay, Clinton and 40 more5 hr
May 17, 8:00 PM CDTTornado WatchSPCFremont, Harrison, Mills, Monona, Montgomery, Page and 3 more5 hr

Nearby

Tornado Watches in Iowa, 2000Tornado Watches in Illinois, 2000Tornado Watches in Missouri, 2000Every tornado 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.