Alert archive / Louisiana / Severe Thunderstorm Warnings in 1990
Severe Thunderstorm Warning 71, NWS New Orleans, LA
NWS New Orleans, LA issued this severe thunderstorm warning at Sep 4, 1990, 10:45 PM CDT for Iberia Parish, Saint Martin Parish, St. Mary Parish, Louisiana. It was in force for 105 min. 1 report 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, 10:45 PM CDT (03:45 UTC)
- Expired
- Sep 5, 1990, 12:30 AM CDT
- In force
- 105 min
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
Counties Iberia Parish, LA, Saint Martin Parish, LA, St. Mary 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, 10:54 PM CDT | Thunderstorm Wind 61 | St. Mary, 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
Lake Charles Mun, LA (KLCH), launched 00:00Z, 3.8 hours before the alert went out and 156 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
- 2374 J/kg
- Mixed-layer CIN
- -30 J/kg
- Mixed-layer LCL
- 1219 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
- 53 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 2.9
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KNEW 050408 SVRNEW LAC045-099-101-050445- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING NATIONAL WEATHER SERVICE NEW ORLEANS LA 1045 PM CDT TUE SEP 4 1990 THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING EFFECTIVE UNTIL 1230 AM CDT FOR RESIDENTS IN THE FOLLOWING PARISHES IN SOUTHEAST LOUISIANA ...IBERIA PARISH...LOWER ST MARTIN PARISH AND ST MARY PARISH... AND THE ADJACENT COASTAL WATERS OF SOUTHEAST LOUISIANA. AT 11 PM CDT RADAR INDICATED A CLUSTER OF SEVERE THUNDERSTORMS OVER ST MARTIN PARISH. THESE STORMS WERE MOVING TOWARDS THE WEST 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. THESE THUNDERSTORMS WILL PRODUCE WINDS EXCEEDING GALE FORCE... ROUGH SEAS... HEAVY RAINFALL... DANGEROUS LIGHTNING AND THE POSSIBILITY OF WATERSPOUTS. SMALL CRAFT SHOULD SEEK SAFE HARBOR IMMEDIATELY.
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, 2 hours 36 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, 1 hour 42 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.
Special weather statement, Sep 4, 10:06 PM CDT, 39 minutes before
LAZ009-050500- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 1005 PM CDT TUE SEP 4 1990 ...BAND OF THUNDERSTORMS CONTINUED OVER PORTIONS OF EAST CENTRAL LOUISIANA... RADAR SHOWED STRONG THUNDERSTORMS NEAR EUNICE...MELVILLE AND PLAQUEMINE LOUISIANA. MOVEMENT WAS WEST AT 20 MPH. RAIN AND THUNDERSTORMS WERE FROM EUNICE THROUGH DONALDSONVILLE TO LAKE PONTCHARTRAIN. MOVEMENT WAS WEST AT 20 MPH. THE SHERIFFS OFFICE AT OPELOUSAS REPORTED SMALL HAIL WITH HEAVY RAIN AND GUSTY WINDS AT PORT BARRE AND KROTZ SPRINGS LOUISIANA. AS THESE THUNDERSTORMS MOVE THROUGH THE AREA...THEY WILL PRODUCE STRONG GUSTY WINDS...HEAVY RAINS...FREQUENT LIGHTNING WITH SOME SMALL HAIL. THESE vCONDITIONS SHOULD LAST UNTIL AROUND MIDNIGHT.
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 | Lafourche, Saint Charles, Saint John the Baptist | 56 min |
| Sep 4, 9:34 PM CDT | Severe Thunderstorm Warning | LIX | Saint James | 56 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.