Alert archive / Louisiana / Severe Thunderstorm Warnings in 1990
Severe Thunderstorm Warning 69, NWS New Orleans, LA
NWS New Orleans, LA issued this severe thunderstorm warning at Sep 4, 1990, 9:34 PM CDT for Lafourche Parish, Saint Charles Parish, Saint John the Baptist Parish, Louisiana. It was in force for 56 min.
The area
The counties it named.
The facts
- Issued
- Sep 4, 1990, 9:34 PM CDT (02:34 UTC)
- Expired
- Sep 4, 1990, 10:30 PM CDT
- In force
- 56 min
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
Counties Lafourche Parish, LA, Saint Charles Parish, LA, Saint John the Baptist Parish, LA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 00:00Z, 2.6 hours before the alert went out and 82 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.
- Mixed-layer CAPE
- 1824 J/kg
- Mixed-layer CIN
- -54 J/kg
- Mixed-layer LCL
- 1659 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 104 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.3
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KNEW 050236 SVRNEW LAC057-089-093-095-050330- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE NEW ORLEANS LA 934 PM CDT TUE SEP 4 1990 THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1030 PM CDT FOR RESIDENTS IN THE FOLLOWING PARISHES IN SOUTHEAST LOUISIANA ...NORTHERN LAFOURCHE PARISH...ST.CHARLES PARISH...ST.JAMES PARISH ...ST.JOHN.BAPTIST PARISH AT 940 PM RADAR INDICATES HHAN AREA OF HEAVY THUNDERSTORMS IN NORTHERN ST CHARLES PARISH. THESE STORMS ARE MOVING TOWARD THE WEST SOUTHWEST AROUND 20 MPH. SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...DESTRUCTIVE HAIL...DEADLYV 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.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, Sep 4, 8:09 PM CDT, 1 hour 25 minutes before
LAZ009-050300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 810 PM CDT TUE SEP 4 1990 ...A BAND OF THUNDERSTORMS WERE MOVING TOWARD THE BATON ROUGE METROPOLITAN AREA... RADAR SHOWED THUNDERSTORMS FROM NEAR INDIAN MOUND TO MONTPELIER. MOVING WEST SOUTHWEST AT 15 MPH. AS THESE THUNDERSTORMS MOVE THROUGH THE AREA...THEY WILL PRODUCE STRONG GUSTY WINDS...HEAVY RAINS...FREQUENT LIGHTNING WITH SOME SMALL HAIL. THESE CONDITIONS SHOULD LAST UNTIL 10 PM TONIGHT.
Special weather statement, Sep 4, 9:03 PM CDT, 31 minutes before
LAZ009-050400- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 905 PM CDT TUE SEP 4 1990 ...BAND OF THUNDERSTORMS CONTINED OVER THE BATON ROUGE METROPOLITAN AREA... RADAR SHOWED THUNDERSTORMS FROM PORT BARRE THROUGH BATON ROUGE SOUTHEAST TO LAKE PONTCHARTRAIN. MOVEMENT WAS WEST AT 20 MPH. AS THESE THUNDERSTORMS MOVE THROUGH THE AREA...THEY WILL PRODUCE STRONG GUSTY WINDS...HEAVY RAINS...FREQUENT LIGHTNING WITH SOME SMALL HA5IL. THESE CONDITIONS SHOULD LAST UNTIL 10 PM TONIGHT.
The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 4, 8:55 PM CDT | Severe Thunderstorm Warning | LIX | Jefferson, Saint Charles, Saint John the Baptist | 65 min |
| Sep 4, 8:55 PM CDT | Severe Thunderstorm Warning | LIX | Tangipahoa | 65 min |
| Sep 4, 8:55 PM CDT | Severe Thunderstorm Warning | LIX | Orleans | 65 min |
| Sep 4, 9:34 PM CDT | Severe Thunderstorm Warning | LIX | Saint James | 56 min |
| Sep 4, 10:45 PM CDT | Severe Thunderstorm Warning | LIX | Iberia, Saint Martin, St. Mary | 105 min |
Nearby
Severe Thunderstorm Warnings in Louisiana, 1990Every 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; the sounding from the Mesonet's radiosonde archive.