Alert archive / Arkansas / Tornado Watches in 2004

Tornado Watch 860

October 18, 200426 counties in Arkansas; 17 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Oct 18, 2004, 5:50 PM CDT for 26 counties in Arkansas; 17 counties in Mississippi. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Oct 18, 2004, 5:50 PM CDT (22:50 UTC)
Expired
Oct 18, 2004, 11:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 43 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jefferson County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Nevada County, AR, Ouachita County, AR, Phillips County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Union County, AR, Bolivar County, MS, Carroll County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Lafayette County, MS, Leflore County, MS, Marshall County, MS, Montgomery County, MS, Panola County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tunica County, MS, Washington County, MS, Yalobusha County, MS

The radar

The Little Rock radar (KLZK), 84 km from the middle of the area, began a volume at 22:52 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

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

IssuedProductOfficeCountiesLasted
Oct 18, 5:50 PM CDTSevere Thunderstorm WarningLZKDallas40 min
Oct 18, 7:14 PM CDTSevere Thunderstorm WarningLZKDallas61 min
Oct 18, 7:26 PM CDTTornado WarningLZKDallas49 min
Oct 18, 7:32 PM CDTSevere Thunderstorm WarningLZKArkansas, Jefferson58 min
Oct 18, 9:01 PM CDTSevere Thunderstorm WarningLZKArkansas44 min
Oct 18, 9:04 PM CDTSevere Thunderstorm WarningLZKJefferson, Lincoln56 min
Oct 18, 10:21 PM CDTSevere Thunderstorm WarningMEGLee, Phillips39 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

Little Rock, AR (KLZK), launched 12:00Z, 10.8 hours before the alert went out and 186 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, Little Rock, AR at 12:00Z on 2004-10-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1504 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, Little Rock, AR at 12:00Z on 2004-10-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 390 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
1504 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
520 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
390 m²/s²
0-3 km storm-relative helicity
482 m²/s²
Significant tornado parameter
3.3
Supercell composite
16.6

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 182254
SEL0  
SPC WW 182250
ARZ000-MSZ000-190400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 860
NWS STORM PREDICTION CENTER NORMAN OK
550 PM CDT MON OCT 18 2004

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

       SOUTHERN ARKANSAS
       NORTHWESTERN MISSISSIPPI

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 550 PM UNTIL 1100
PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 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 45 MILES SOUTH SOUTHWEST OF HOT SPRINGS
ARKANSAS TO 15 MILES SOUTH SOUTHEAST OF OXFORD MISSISSIPPI.

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 857...WW 858...WW 859...

DISCUSSION...A WEAK AREA OF CONVERGENCE WITH CONVECTION EXTENDS FROM
SOUTH OF LIT TO TXK. STORMS ARE EXPECTED TO INTENSIFY ALONG THIS
AXIS AND SHIFT EWD DURING THE EVENING AS STRONG FORCING ASSOCIATED
WITH A 250 MB JET MAX INCREASES THE UPPER LEVEL DIVERGENCE/LOW LEVEL
CONVERGENCE.  A VERY MOIST BOUNDARY LAYER AND STRONG LOW LEVEL SHEAR
IS FAVORABLE FOR SUPERCELLS WITH LARGE HAIL AND A FEW TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.
MEAN STORM MOTION VECTOR 26030.


...IMY

344,0932 350,0892 331,0892 330,0932

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 17, 11:30 PM CDTSevere Thunderstorm WatchSPCBaxter, Clay, Fulton, Greene, Marion, Randolph and 1 more6 hr
Oct 18, 2:19 AM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Clark, Clay and 42 more56 min
Oct 18, 4:40 AM CDTMesoscale DiscussionSPCClay, Greene, Randolph, Sharp35 min
Oct 18, 7:44 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Clay, Cleburne and 43 more61 min
Oct 18, 9:45 AM CDTTornado WatchSPCArkansas, Calhoun, Cleveland, Dallas, Desha, Drew and 12 more5 hr
Oct 18, 11:29 AM CDTMesoscale DiscussionSPCArkansas, Calhoun, Cleveland, Dallas, Desha, Drew and 12 more91 min
Oct 18, 2:18 PM CDTMesoscale DiscussionSPCArkansas, Calhoun, Cleveland, Dallas, Desha, Drew and 12 more57 min
Oct 18, 4:05 PM CDTTornado WatchSPCBaxter, Clay, Cleburne, Craighead, Crittenden, Cross and 15 more5 hr
Oct 18, 5:21 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 22 more114 min

Nearby

Tornado Watches in Arkansas, 2004Tornado Watches in Mississippi, 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.