Alert archive / Arkansas / Tornado Watches in 1999

Tornado Watch 721

December 4, 199931 counties in Arkansas; 9 parishes in Louisiana

The Storm Prediction Center issued this tornado watch at Dec 4, 1999, 4:00 PM CST for 31 counties in Arkansas; 9 parishes in Louisiana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Dec 4, 1999, 4:00 PM CST (22:00 UTC)
Expired: Dec 4, 1999, 9:00 PM CST
In force: 5 hr
Issued by: the Storm Prediction Center

All 40 counties

Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleburne County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Dallas County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Jefferson County, AR, Johnson County, AR, Lafayette County, AR, Logan County, AR, Lonoke County, AR, Miller County, AR, Montgomery County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Pope County, AR, Pulaski County, AR, Saline County, AR, Union County, AR, Van Buren County, AR, White County, AR, Yell County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Ouachita Parish, LA, Union Parish, LA, Webster Parish, LA

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Dec 4, 4:00 PM CST	Severe Thunderstorm Warning	LZK	Logan	50 min
Dec 4, 4:16 PM CST	Severe Thunderstorm Warning	LZK	Hot Spring	64 min
Dec 4, 4:49 PM CST	Severe Thunderstorm Warning	LZK	Garland	51 min
Dec 4, 4:57 PM CST	Tornado Warning	LZK	Hot Spring	48 min
Dec 4, 5:23 PM CST	Tornado Warning	LZK	Saline	47 min
Dec 4, 5:32 PM CST	Severe Thunderstorm Warning	LZK	Pope	63 min
Dec 4, 5:47 PM CST	Severe Thunderstorm Warning	LZK	Conway, Perry, Yell	48 min
Dec 4, 5:49 PM CST	Severe Thunderstorm Warning	LZK	Grant	51 min
Dec 4, 5:58 PM CST	Severe Thunderstorm Warning	LZK	Calhoun, Ouachita	47 min
Dec 4, 6:05 PM CST	Severe Thunderstorm Warning	LZK	Pulaski	65 min
Dec 4, 6:13 PM CST	Severe Thunderstorm Warning	LZK	Saline	17 min
Dec 4, 6:25 PM CST	Severe Thunderstorm Warning	LZK	Faulkner	50 min
Dec 4, 6:32 PM CST	Severe Thunderstorm Warning	LZK	Van Buren	63 min
Dec 4, 6:36 PM CST	Severe Thunderstorm Warning	LZK	Pope	19 min
Dec 4, 6:55 PM CST	Severe Thunderstorm Warning	LZK	Lonoke	65 min

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 10.0 hours before the alert went out and 137 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 143 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 602 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 348 m²/s²
0-3 km storm-relative helicity: 374 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.1

Open this sounding in Storm Lab

The text

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

147 
WWUS9 KMKC 042129
SEL1  
MKC WW 042129
ARZ000-LAZ000-050300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 721
STORM PREDICTION CENTER NORMAN OK
329 PM CST SAT DEC 4 1999

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

   ARKANSAS                           
   NORTHERN LOUISIANA                          

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 400 PM UNTIL 900
PM CST.

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

THE TORNADO WATCH AREA IS ALONG AND 60 STATUTE MILES EAST AND WEST
OF A LINE FROM 50 MILES EAST SOUTHEAST OF SHREVEPORT LOUISIANA TO
75 MILES NORTH NORTHWEST OF LITTLE ROCK ARKANSAS.

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...THIS TORNADO WATCH REPLACES SEVERE
THUNDERSTORM WATCH NUMBER 720.  WATCH NUMBER 720 WILL NOT BE IN
EFFECT AFTER 400 PM CST.

DISCUSSION...THREAT FOR DAMAGING WIND GUSTS AND ISOLATED TORNADOES
EXPECTED TO CONTINUE THIS EVENING AHEAD OF STRONG UPPER TROUGH. LOW
LEVEL WINDS HAVE BACKED SUBSTANTIALLY DURING THE PAST HOUR...WHICH
HAS INCREASED LOW LEVEL HODOGRAPH CURVATURE.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. 
MEAN STORM MOTION VECTOR 23035.


...VESCIO

321,0940 354,0934 354,0914 321,0920

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 3, 8:45 PM CST	Severe Thunderstorm Watch	SPC	Benton, Boone, Carroll, Washington	5 hr
Dec 4, 11:00 AM CST	Severe Thunderstorm Watch	SPC	Hempstead, Howard, Lafayette, Little River, Miller, Montgomery and 5 more	6 hr

Nearby

Tornado Watches in Arkansas, 1999 Tornado Watches in Louisiana, 1999 Every tornado watch in 1999

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.