Alert archive / Louisiana / Tornado Warnings in 1990

Tornado Warning 12, NWS New Orleans, LA

March 29, 1990Saint Tammany Parish, Louisiana

NWS New Orleans, LA issued this tornado warning at Mar 29, 1990, 11:24 PM CST for Saint Tammany Parish, Louisiana. It was in force for 66 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Mar 29, 1990, 11:24 PM CST (05:24 UTC)
Expired: Mar 30, 1990, 12:30 AM CST
In force: 66 min
Issued by: NWS New Orleans, LA
Area: Whole counties

County Saint Tammany Parish, LA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

Time	Report	Where	Remark
Mar 29, 11:50 PM CST	Thunderstorm Wind 55	St. Tammany, LA
Mar 30, 12:10 AM CST	Thunderstorm Wind 0	St. Tammany, LA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 5.4 hours before the alert went out and 30 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: 16 J/kg
Mixed-layer CIN: -222 J/kg
Mixed-layer LCL: 1008 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 78 m²/s²
0-3 km storm-relative helicity: 158 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KNEW 300526
TORNEW
LAC103-300630-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1124 PM CST THU MAR 29 1990
 
THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL 1230 AM CST
FOR RESIDENTS IN THE FOLLOWING PARISHES
 
IN SOUTHEAST LOUISIANA
 
   ...ST.TAMMANY PARISH
 
NATIONAL WEATHER SERVICE RADAR AT SLIDELL AT 1118 PMCST INDICATED
A POSSIBLE TORNADO OVER THE WEST PORTION OF LAKE PONTCHARTRAIN
MOVING NORTHEAST ABOUT 40 MPH. THIS STORM HAS PRODUCED POSSIBLE
TORNADOES AND WIND DAMAGE WEST OF THE NEW ORLEANS METRO AREA
DURING THE PAST ONE TO ONE AND HALF HOURS.
 
 
THIS IS A DANGEROUS STORM SITUATION.  ACT QUICKLY.  IF YOU ARE
IN THE PATH OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF
AVAILABLE.  OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST
FLOOR POSSIBLE.  AVOID WINDOWS.  ABANDON CARS AND MOBILE HOMES
FOR A REINFORCED BUILDING OR GET INTO A DITCH OR CULVERT.

The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 29, 8:06 PM CST	Severe Thunderstorm Warning	LIX	Iberia, Saint Martin, St. Mary	69 min
Mar 29, 8:24 PM CST	Severe Thunderstorm Warning	LIX	Saint Landry	51 min
Mar 29, 8:58 PM CST	Severe Thunderstorm Warning	LIX	Iberville, Pointe Coupee	62 min
Mar 29, 9:17 PM CST	Severe Thunderstorm Warning	LIX	Assumption, Lafourche, Saint James, Terrebonne	58 min
Mar 29, 9:25 PM CST	Severe Thunderstorm Warning	LIX	West Baton Rouge, West Feliciana	65 min
Mar 29, 9:43 PM CST	Severe Thunderstorm Warning	LIX	Ascension, East Baton Rouge, East Feliciana	62 min
Mar 29, 10:11 PM CST	Severe Thunderstorm Warning	LIX	Livingston, Saint Helena	64 min
Mar 29, 10:17 PM CST	Severe Thunderstorm Warning	LIX	Lafourche, Saint Charles, Saint John the Baptist	58 min
Mar 29, 10:17 PM CST	Severe Thunderstorm Warning	LIX	Terrebonne	58 min
Mar 29, 10:34 PM CST	Tornado Warning	LIX	Lafourche	26 min
Mar 29, 10:44 PM CST	Tornado Warning	LIX	Jefferson, Saint Charles	61 min
Mar 29, 10:56 PM CST	Tornado Warning	LIX	Orleans	64 min
Mar 30, 12:22 AM CST	Tornado Warning	LIX	Saint Tammany	48 min

Nearby

Tornado Warnings in Louisiana, 1990 Every tornado warning in 1990 Tornadoes in 1990

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.