Alert archive / Alabama / Tornado Watches in 2004

Tornado Watch 857

October 18, 20048 counties in Alabama; Franklin County, Giles County, Lincoln County, Tennessee

The Storm Prediction Center issued this tornado watch at Oct 18, 2004, 3:20 PM CDT for 8 counties in Alabama; Franklin County, Giles County, Lincoln County, Tennessee. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Oct 18, 2004, 3:20 PM CDT (20:20 UTC)
Expired
Oct 18, 2004, 8:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Colbert County, AL, Franklin County, AL, Jackson County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Morgan County, AL, Franklin County, TN, Giles County, TN, Lincoln County, TN

The radar

The Northeast Alabama radar (KHTX), 99 km from the middle of the area, began a volume at 20:23 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

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

IssuedProductOfficeCountiesLasted
Oct 18, 3:35 PM CDTTornado WarningHUNColbert, Lauderdale40 min
Oct 18, 4:05 PM CDTTornado WarningHUNColbert, Lauderdale40 min
Oct 18, 4:42 PM CDTTornado WarningHUNLauderdale48 min
Oct 18, 5:28 PM CDTTornado WarningHUNLauderdale47 min
Oct 18, 5:53 PM CDTTornado WarningHUNLimestone37 min
Oct 18, 6:03 PM CDTTornado WarningOHXGiles, Lawrence27 min
Oct 18, 6:10 PM CDTTornado WarningHUNLauderdale35 min
Oct 18, 6:27 PM CDTTornado WarningHUNLimestone33 min
Oct 18, 6:31 PM CDTTornado WarningOHXGiles29 min
Oct 18, 6:57 PM CDTSevere Thunderstorm WarningHUNLincoln, Moore48 min
Oct 18, 7:27 PM CDTTornado WarningHUNLincoln48 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

Nashville Metro, TN (KBNA), launched 12:00Z, 8.3 hours before the alert went out and 150 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 2004-10-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Nashville Metro, TN at 12:00Z on 2004-10-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 198 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
920 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
198 m²/s²
0-3 km storm-relative helicity
142 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 182026
SEL7  
SPC WW 182020
ALZ000-TNZ000-190100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 857
NWS STORM PREDICTION CENTER NORMAN OK
320 PM CDT MON OCT 18 2004

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

       NORTHERN ALABAMA
       SOUTHERN MIDDLE TENNESSEE

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 320 PM UNTIL 800
PM CDT.

TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS ALONG AND 30 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 25 MILES WEST OF MUSCLE SHOALS ALABAMA TO 55
MILES EAST NORTHEAST OF HUNTSVILLE ALABAMA.

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 856...

DISCUSSION...INTENSE SUPERCELL NERN MS WILL MOVE EWD ALONG/TN/AL
BORDER WHERE SHEAR PROFILES REMAIN VERY SUPPORTIVE FOR ROTATION. AIR
MASS CONTINUES TO DESTABILIZE EWD INTO NRN AL THUS SUPERCELL
EXPECTED TO MAINTAIN INTENSITY WITH POSSIBLE TORNADOES THRU
REMAINDER OF AFTN.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 27035.


...HALES

351,0880 352,0855 343,0855 341,0880

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 18, 6:02 PM CDTMesoscale DiscussionSPCColbert, Franklin, Jackson, Lauderdale, Lawrence, Limestone and 2 more88 min
Oct 17, 11:30 PM CDTSevere Thunderstorm WatchSPCLake, Obion6 hr
Oct 18, 2:19 AM CDTMesoscale DiscussionSPCDyer, Lake, Obion56 min
Oct 18, 4:40 AM CDTMesoscale DiscussionSPCLake, Obion35 min
Oct 18, 7:44 AM CDTMesoscale DiscussionSPCCarroll, Chester, Crockett, Dyer, Fayette, Gibson and 10 more61 min
Oct 18, 9:45 AM CDTTornado WatchSPCFayette, Hardeman, McNairy, Shelby5 hr
Oct 18, 11:29 AM CDTMesoscale DiscussionSPCFayette, Hardeman, McNairy, Shelby91 min
Oct 18, 1:55 PM CDTMesoscale DiscussionSPCStewart95 min
Oct 18, 2:18 PM CDTMesoscale DiscussionSPCFayette, Hardeman, McNairy, Shelby57 min
Oct 18, 4:05 PM CDTTornado WatchSPCCarroll, Chester, Crockett, Dyer, Fayette, Gibson and 12 more5 hr

Nearby

Tornado Watches in Alabama, 2004Tornado Watches in Tennessee, 2004Every tornado watch in 2004

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.