Alert archive / Louisiana / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 65, NWS New Orleans, LA

September 4, 1990Tangipahoa Parish, Washington Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Sep 4, 1990, 6:51 PM CDT for Tangipahoa Parish, Washington Parish, Louisiana. It was in force for 69 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: Sep 4, 1990, 6:51 PM CDT (23:51 UTC)
Expired: Sep 4, 1990, 8:00 PM CDT
In force: 69 min
Issued by: NWS New Orleans, LA
Area: Whole counties

Counties Tangipahoa Parish, LA, Washington 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
Sep 4, 7:00 PM CDT	Thunderstorm Wind 0	Washington, LA
Sep 4, 7:15 PM CDT	Thunderstorm Wind 0	Tangipahoa, 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 12:00Z, 11.9 hours before the alert went out and 74 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: 1207 J/kg
Mixed-layer CIN: -92 J/kg
Mixed-layer LCL: 1245 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 80 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KNEW 042353
SVRNEW
LAC105-117-050100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
651 PM CDT TUE SEP 4 1990
 
THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  800 PM CDT
FOR RESIDENTS IN THE FOLLOWING PARISHES
 
IN SOUTHEAST LOUISIANA
 
   ...NORTHERN TANGIPAHOA PARISH...NORTHWESTERN WASHINGTON PARISH
 
AT 650 PM CDT RADAR INDICATED A SEVERE THUNDERSTORMS 15 MILES
NORTHWEST OF FRANKLINTON LOUISIANA IN WASHINGTON PARISH. THIS
STORM WAS MOVING TOWARDS THE SOUTHWEST AT ABOUT 20 MILES AN HOUR.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

Nearby

Severe Thunderstorm Warnings in Louisiana, 1990 Every severe thunderstorm warning 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.