Alert archive / Arkansas / Tornado Watches in 2001

Tornado Watch 851

December 16, 200110 counties in Arkansas; 6 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Dec 16, 2001, 9:45 PM CST for 10 counties in Arkansas; 6 counties in Mississippi. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Dec 16, 2001, 9:45 PM CST (03:45 UTC)
Expired: Dec 17, 2001, 3:00 AM CST
In force: 5 hr
Issued by: the Storm Prediction Center

Counties Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Cleveland County, AR, Columbia County, AR, Desha County, AR, Drew County, AR, Lincoln County, AR, Union County, AR, Bolivar County, MS, Grenada County, MS, Leflore County, MS, Sunflower County, MS, Tallahatchie County, MS, Washington County, MS

The radar

The Little Rock radar (KLZK), 161 km from the middle of the area, began a volume at 03:49 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

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

Issued	Product	Office	Counties	Lasted
Dec 17, 12:37 AM CST	Flash Flood Warning	LZK	Arkansas, Bradley, Calhoun, Cleveland, Desha, Drew and 5 more	4 hr
Dec 17, 1:07 AM CST	Flash Flood Warning	JAN	Ashley, Chicot	3 hr
Dec 17, 2:42 AM CST	Flash Flood Warning	JAN	Humphreys, Leflore, Sunflower	3 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 3.8 hours before the alert went out and 201 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: 875 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 500 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 243 m²/s²
0-3 km storm-relative helicity: 295 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 6.2

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 170339
SEL1  
SPC WW 170329
ARZ000-MSZ000-170900-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 851
STORM PREDICTION CENTER NORMAN OK
929 PM CST SUN DEC 16 2001

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

   SOUTHEAST ARKANSAS                           
   WESTERN MISSISSIPPI                        

EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 945 PM UNTIL
300 AM CST.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 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 35 MILES EAST SOUTHEAST OF EL DORADO ARKANSAS TO 40
MILES NORTH NORTHEAST OF GREENVILLE 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 850...

DISCUSSION...SURFACE LOW NOW N OF SHV EXPECTED TO TRACK NEWD
THROUGH THE OVERNIGHT.  SQUALL LINE EXTENDING S FROM LOW EXPECTED
TO BUILD SOMEWHAT TO THE N AS THE LINE CONTINUES EWD.  STRENGTH OF
SHEAR SUGGESTS THAT LINE WILL CONTINUE TO CONTAIN EMBEDDED
SUPERCELLS...AND POSSIBLY AN ISOLATED TORNADO OR TWO.  THREAT WILL
ALSO EXIST FOR ISOLATED TORNADOES IMMEDIATELY AHEAD OF LOW
TRACK...WHERE BOTH LOW LEVEL AND DEEP SHEAR WILL BE MAXIMIZED AND
AIR MASS RECOVERY WILL CONTINUE.  

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH...EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. 
MEAN STORM MOTION VECTOR 23040.

...CORFIDI

340,0892 330,0905 330,0933 340,0920

Nearby

Tornado Watches in Arkansas, 2001 Tornado Watches in Mississippi, 2001 Every tornado watch in 2001

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.