Alert archive / Iowa / Tornado Watches in 2003

Tornado Watch 698

July 9, 200371 counties in Iowa

The Storm Prediction Center issued this tornado watch at Jul 9, 2003, 2:00 PM CDT for 71 counties in Iowa. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 9, 2003, 2:00 PM CDT (19:00 UTC)
Expired
Jul 9, 2003, 8:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 71 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Benton County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Buena Vista County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Cherokee County, IA, Chickasaw County, IA, Clarke County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Dickinson County, IA, Emmet County, IA, Floyd County, IA, Franklin County, IA, Fremont County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Howard County, IA, Humboldt County, IA, Ida County, IA, Iowa County, IA, Jasper County, IA, Keokuk County, IA, Kossuth County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mills County, IA, Mitchell County, IA, Monroe County, IA, Montgomery County, IA, O'Brien County, IA, Osceola County, IA, Page County, IA, Palo Alto County, IA, Pocahontas County, IA, Polk County, IA, Pottawattamie County, IA, Poweshiek County, IA, Ringgold County, IA, Sac County, IA, Shelby County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Winnebago County, IA, Worth County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 42 km from the middle of the area, began a volume at 19:02 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.

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 9, 2:11 PM CDTSevere Thunderstorm WarningOAXShelby49 min
Jul 9, 2:52 PM CDTSevere Thunderstorm WarningOAXPottawattamie38 min
Jul 9, 2:58 PM CDTSevere Thunderstorm WarningOAXShelby32 min
Jul 9, 3:01 PM CDTSevere Thunderstorm WarningDMXAudubon59 min
Jul 9, 3:27 PM CDTSevere Thunderstorm WarningOAXShelby33 min
Jul 9, 3:38 PM CDTSevere Thunderstorm WarningDMXCass52 min
Jul 9, 4:03 PM CDTSevere Thunderstorm WarningDMXAudubon42 min
Jul 9, 4:08 PM CDTSevere Thunderstorm WarningOAXMills37 min
Jul 9, 4:13 PM CDTSevere Thunderstorm WarningDMXHardin47 min
Jul 9, 4:17 PM CDTSevere Thunderstorm WarningOAXPottawattamie28 min
Jul 9, 4:25 PM CDTSevere Thunderstorm WarningDMXCass50 min
Jul 9, 4:48 PM CDTSevere Thunderstorm WarningDMXAdair, Guthrie42 min
Jul 9, 4:58 PM CDTSevere Thunderstorm WarningDMXAdams47 min
Jul 9, 4:58 PM CDTSevere Thunderstorm WarningOAXMontgomery32 min
Jul 9, 5:51 PM CDTTornado WarningDMXHamilton9 min
Jul 9, 6:10 PM CDTSevere Thunderstorm WarningDMXRinggold50 min
Jul 9, 6:22 PM CDTSevere Thunderstorm WarningDMXHamilton, Hardin38 min
Jul 9, 6:22 PM CDTSevere Thunderstorm WarningDMXDavis53 min
Jul 9, 7:28 PM CDTSevere Thunderstorm WarningDMXDecatur, Wayne32 min
Jul 9, 7:36 PM CDTSevere Thunderstorm WarningDMXAppanoose, Wayne24 min
Jul 9, 7:53 PM CDTSevere Thunderstorm WarningDVNKeokuk52 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

Omaha, NE (KOAX), launched 12:00Z, 7.0 hours before the alert went out and 184 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, Omaha, NE at 12:00Z on 2003-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Omaha, NE at 12:00Z on 2003-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -30 square meters per square second.193958Sfc1 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
3 J/kg
Mixed-layer CIN
-462 J/kg
Mixed-layer LCL
2332 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-30 m²/s²
0-3 km storm-relative helicity
-17 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.

000 
WWUS20 KWNS 091902
SEL8  
SPC WW 091900
IAZ000-100100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 698 
NWS STORM PREDICTION CENTER NORMAN OK 
200 PM CDT WED JUL 9 2003

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

       IOWA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 200 PM UNTIL
800 PM CDT.

TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS ALONG AND 95 STATUTE MILES EAST AND WEST
OF A LINE FROM 35 MILES NORTHWEST OF MASON CITY IOWA TO 5 MILES
SOUTH SOUTHEAST OF LAMONI IOWA.

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 695...WW 696...WW 697...


DISCUSSION...TEMPERATURES HAVE WARMED INTO THE MID 80S IN SWRN IA
AND WILL OVERSPREAD THE AREA AS STRONG FORCING SPREADS EWD ACROSS
IA. 40-50 KT DEEP LAYER SHEAR AND MLCAPE VALUES INCREASING TO 2000
J/KG WILL BE FAVORABLE FOR SUPERCELLS. THE GREATEST THREAT WILL BE
LARGE HAIL AND WIND DAMAGE...THOUGH THE SHEAR/INSTABILITY IS ALSO
FAVORABLE FOR A FEW TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 26035.


...IMY

432,0915 403,0920 403,0954 432,0954

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 8, 8:59 PM CDTMesoscale DiscussionSPCAppanoose, Clarke, Davis, Decatur, Des Moines, Henry and 9 more2 hr
Jul 9, 1:10 AM CDTSevere Thunderstorm WatchSPCAdair, Adams, Appanoose, Audubon, Boone, Buena Vista and 55 more6 hr
Jul 9, 4:15 AM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Boone, Buena Vista and 50 more2 hr
Jul 9, 1:08 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Benton, Black Hawk, Boone and 47 more67 min
Jul 9, 3:15 PM CDTTornado WatchSPCAllamakee, Buchanan, Cedar, Clayton, Clinton, Delaware and 13 more6 hr
Jul 9, 5:38 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Benton, Black Hawk, Boone and 61 more97 min

Nearby

Tornado 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.