Alert archive / Tennessee / Tornado Watches in 2000

Tornado Watch 189

April 20, 200037 counties in Tennessee

The Storm Prediction Center issued this tornado watch at Apr 20, 2000, 5:15 PM CDT for 37 counties in Tennessee. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 20, 2000, 5:15 PM CDT (22:15 UTC)
Expired
Apr 20, 2000, 9:00 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
All 37 counties

Bedford County, TN, Bledsoe County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Jackson County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Rutherford County, TN, Scott County, TN, Sequatchie County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Williamson County, TN, Wilson County, TN

The radar

The Nashville radar (KOHX), 70 km from the middle of the area, began a volume at 22:16 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

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

IssuedProductOfficeCountiesLasted
Apr 20, 5:27 PM CDTSevere Thunderstorm WarningOHXMaury48 min
Apr 20, 5:34 PM CDTSevere Thunderstorm WarningOHXMacon, Sumner, Trousdale41 min
Apr 20, 5:39 PM CDTTornado WarningOHXLewis, Maury51 min
Apr 20, 5:49 PM CDTTornado WarningOHXDavidson, Rutherford, Williamson26 min
Apr 20, 6:19 PM CDTTornado WarningOHXWilson26 min
Apr 20, 6:24 PM CDTSevere Thunderstorm WarningOHXMarshall21 min
Apr 20, 6:24 PM CDTTornado WarningOHXTrousdale, Wilson36 min
Apr 20, 6:24 PM CDTTornado WarningOHXMacon36 min
Apr 20, 6:37 PM CDTTornado WarningOHXDeKalb23 min
Apr 20, 6:41 PM CDTTornado WarningOHXBedford49 min
Apr 20, 6:54 PM CDTTornado WarningOHXPutnam51 min
Apr 20, 7:09 PM CDTTornado WarningOHXCoffee51 min
Apr 20, 7:15 PM CDTSevere Thunderstorm WarningOHXMarshall15 min
Apr 20, 7:31 PM CDTSevere Thunderstorm WarningOHXBedford44 min
Apr 20, 7:36 PM CDTSevere Thunderstorm WarningOHXOverton39 min
Apr 20, 7:41 PM CDTTornado WarningOHXWarren34 min
Apr 20, 7:53 PM CDTTornado WarningOHXFentress37 min
Apr 20, 7:58 PM CDTSevere Thunderstorm WarningOHXCoffee32 min
Apr 20, 8:08 PM CDTSevere Thunderstorm WarningMRXBledsoe, Sequatchie62 min
Apr 20, 8:11 PM CDTTornado WarningOHXCoffee, Grundy34 min
Apr 20, 8:12 PM CDTSevere Thunderstorm WarningMRXMorgan, Scott28 min
Apr 20, 8:16 PM CDTTornado WarningOHXVan Buren14 min
Apr 20, 8:23 PM CDTSevere Thunderstorm WarningOHXFentress37 min
Apr 20, 8:32 PM CDTSevere Thunderstorm WarningOHXFranklin28 min
Apr 20, 8:36 PM CDTSevere Thunderstorm WarningMRXCampbell, Scott44 min
Apr 20, 8:44 PM CDTTornado WarningMRXSequatchie46 min
Apr 20, 8:45 PM CDTTornado WarningMRXCampbell, Scott30 min
Apr 20, 8:48 PM CDTSevere Thunderstorm WarningMRXMarion62 min
Apr 20, 8:50 PM CDTSevere Thunderstorm WarningOHXGrundy25 min

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 10.3 hours before the alert went out and 57 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, Nashville Metro, TN at 12:00Z on 2000-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Nashville Metro, TN at 12:00Z on 2000-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 319 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1180 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
319 m²/s²
0-3 km storm-relative helicity
324 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

339 
WWUS9 KMKC 202154
SEL9  

SEL9  
MKC WW 202154
TNZ000-210200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 189
STORM PREDICTION CENTER NORMAN OK
454 PM CDT THU APR 20 2000

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

   MIDDLE TENNESSEE                          

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 515 PM UNTIL 900
PM CDT.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO
80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 75 STATUTE MILES EAST AND WEST
OF A LINE FROM 80 MILES SOUTH OF NASHVILLE TENNESSEE TO 50 MILES
NORTH NORTHWEST OF CROSSVILLE TENNESSEE.

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 187...WW 188...

DISCUSSION...THUNDERSTORMS HAVE INCREASED OVER MIDDLE TN...WITH
SOME POTENTIAL FOR SUPERCELLS GIVEN STRONG DEEP LAYER SHEAR.
ACTIVITY SHOULD BEGIN TO DIMINISH LATER THIS EVENING AS UPPER
SYSTEM MOVES BY THE AREA.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 24045.

...VESCIO

363,0840 345,0852 345,0880 363,0864

Nearby

Tornado Watches in Tennessee, 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.