Alert archive / Iowa / Tornado Watches in 2000

Tornado Watch 648

August 5, 200064 counties in Iowa

The Storm Prediction Center issued this tornado watch at Aug 5, 2000, 6:30 PM CDT for 64 counties in Iowa. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Aug 5, 2000, 6:30 PM CDT (23:30 UTC)
Expired
Aug 6, 2000, 12:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
All 64 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, Chickasaw County, IA, Clarke County, IA, Crawford County, IA, Dallas County, IA, Decatur County, IA, Emmet County, IA, Fayette 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, Jasper 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, 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, Winneshiek County, IA, Worth County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 34 km from the middle of the area, began a volume at 23:39 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

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

IssuedProductOfficeCountiesLasted
Aug 5, 7:31 PM CDTTornado WarningOAXHarrison, Shelby29 min
Aug 5, 7:45 PM CDTSevere Thunderstorm WarningDMXCrawford30 min
Aug 5, 7:57 PM CDTTornado WarningOAXShelby33 min
Aug 5, 8:30 PM CDTSevere Thunderstorm WarningOAXShelby30 min
Aug 5, 8:34 PM CDTTornado WarningOAXPottawattamie31 min
Aug 5, 8:35 PM CDTSevere Thunderstorm WarningDMXCass40 min
Aug 5, 9:12 PM CDTSevere Thunderstorm WarningDMXAdair, Cass33 min
Aug 5, 9:43 PM CDTSevere Thunderstorm WarningDMXAdair32 min

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.5 hours before the alert went out and 193 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 2000-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2290 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 2000-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 152 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
2290 J/kg
Mixed-layer CIN
-181 J/kg
Mixed-layer LCL
813 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
152 m²/s²
0-3 km storm-relative helicity
173 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

072 
WWUS9 KMKC 052306
SEL8  

SEL8  
MKC WW 052259
IAZ000-060500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 648
STORM PREDICTION CENTER NORMAN OK
559 PM CDT SAT AUG 5 2000

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

   MOST OF IOWA                               

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 630 PM UNTIL
MIDNIGHT CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 85 STATUTE MILES EAST AND WEST
OF A LINE FROM 10 MILES WEST OF LAMONI IOWA TO 25 MILES NORTH OF
MASON CITY 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.


DISCUSSION...THUNDERSTORMS INCREASING ALONG SURFACE TROUGH AND IN
ADVANCE OF UPPER LEVEL SHORT WAVE AS THEY APPROACH AREA OF CAPES
AOA 3000 J/KG. A FEW TORNADOES MAY DEVELOP NEAR INTERSECTION OF
SURFACE LOW AND OUTFLOW BOUNDARY WHERE LOW LEVEL FORCING AND
VERTICAL WIND SHEAR WILL BE ENHANCED. ELSEWHERE PRIMARY THREAT WILL
BE LARGE HAIL AND DAMAGING WINDS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 26035.


...ROGASH

433,0913 403,0923 403,0954 433,0950

Nearby

Tornado Watches in Iowa, 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.