Alert archive / Louisiana / Tornado Watches in 1997

Tornado Watch 52

February 20, 199729 parishes in Louisiana; Newton County, Sabine County, Texas

The Storm Prediction Center issued this tornado watch at Feb 20, 1997, 7:30 PM CST for 29 parishes in Louisiana; Newton County, Sabine County, Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Feb 20, 1997, 7:30 PM CST (01:30 UTC)
Expired: Feb 21, 1997, 1:00 AM CST
In force: 6 hr
Issued by: the Storm Prediction Center

All 31 counties

Acadia Parish, LA, Allen Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Evangeline Parish, LA, Grant Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Sabine Parish, LA, Saint Landry Parish, LA, Union Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA, Newton County, TX, Sabine County, TX

The radar

The Ft Polk radar (KPOE), 63 km from the middle of the area, began a volume at 01:32 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.

Issued	Product	Office	Counties	Lasted
Feb 20, 8:35 PM CST	Severe Thunderstorm Warning	SHV	Bossier	40 min
Feb 20, 8:44 PM CST	Severe Thunderstorm Warning	SHV	Webster	61 min
Feb 20, 8:51 PM CST	Flash Flood Warning	SHV	Bossier, Caddo, Webster	3 hr
Feb 20, 9:20 PM CST	Severe Thunderstorm Warning	SHV	Claiborne	55 min
Feb 20, 9:51 PM CST	Severe Thunderstorm Warning	SHV	Bienville	69 min
Feb 20, 10:02 PM CST	Severe Thunderstorm Warning	SHV	Lincoln	58 min
Feb 20, 10:12 PM CST	Severe Thunderstorm Warning	SHV	Union	63 min
Feb 20, 10:16 PM CST	Severe Thunderstorm Warning	SHV	Claiborne	29 min
Feb 20, 11:54 PM CST	Severe Thunderstorm Warning	SHV	Ouachita	51 min
Feb 20, 11:55 PM CST	Severe Thunderstorm Warning	LCH	Acadia, Jefferson Davis	50 min
Feb 21, 12:48 AM CST	Severe Thunderstorm Warning	LCH	Avoyelles, Saint Landry	42 min

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 1.5 hours before the alert went out and 128 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: 820 J/kg
Mixed-layer CIN: -3 J/kg
Mixed-layer LCL: 620 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 302 m²/s²
0-3 km storm-relative helicity: 415 m²/s²
Significant tornado parameter: 1.9
Supercell composite: 7.0

Open this sounding in Storm Lab

The text

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

366 
WWUS9 KMKC 210112
SEL2  
MKC WW 210112
LAZ000-210700-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 52
STORM PREDICTION CENTER NORMAN OK
712 PM CST THU FEB 20 1997

A...THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR

   PARTS OF WESTERN AND CENTRAL LOUISIANA                         
   AND ADJACENT COASTAL WATERS

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING UNTIL 100 AM CST.

TORNADOES...LARGE HAIL...DANGEROUS LIGHTNING AND DAMAGING
THUNDERSTORM WINDS ARE POSSIBLE IN THESE AREAS.


THE TORNADO WATCH AREA IS ALONG AND 55 STATUTE MILES EAST AND WEST
OF A LINE FROM 65 MILES NORTHEAST OF SHREVEPORT LOUISIANA TO 45
MILES WEST SOUTHWEST OF INTRACOASTAL CITY LOUISIANA.

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.
$$

C...TORNADOES AND A FEW SVR TSTMS WITH HAIL SFC AND ALF TO 1
INCHES.  EXTRM TURBC AND SFC WIND GUSTS TO 70 KNOTS.  A FEW CBS
WITH MAX TOPS TO 450.  MEAN WIND VECTOR 19040.

D...LINE OF THUNDERSTORMS APPROACHING WATCH AREA ALONG STRONG MID
LEVEL VORT AXIS. CAPES MARGINAL...NEAR 1000 J/KG...BUT 50 KT LOW
LEVEL JET AND 70 KT MID LEVEL FLOW INDICATES SHEAR MAY SUPPORT A
FEW SUPERCELLS.

E...OTR TSTMS...  CONT..WW 50..WW 51..

...ROGASH

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 20, 11:45 PM CST	Tornado Watch	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Caldwell and 32 more	5 hr
Feb 20, 6:00 PM CST	Tornado Watch	SPC	Cass	6 hr

Nearby

Tornado Watches in Louisiana, 1997 Tornado Watches in Texas, 1997 Every tornado watch in 1997

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.