Alert archive / Louisiana / Tornado Warnings in 1990
Tornado Warning 20, NWS New Orleans, LA
NWS New Orleans, LA issued this tornado warning at Dec 18, 1990, 10:58 AM CST for Saint Charles Parish, Louisiana. It was in force for 62 min.
The area
The counties it named.
The facts
- Issued
- Dec 18, 1990, 10:58 AM CST (16:58 UTC)
- Expired
- Dec 18, 1990, 12:00 PM CST
- In force
- 62 min
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
County Saint Charles 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 12:00Z, 5.0 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.
- Mixed-layer CAPE
- 97 J/kg
- Mixed-layer CIN
- -40 J/kg
- Mixed-layer LCL
- 593 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 39 m²/s²
- 0-3 km storm-relative helicity
- 118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KNEW 181659 TORNEW LAC089-103-105-181800- BULLETIN - EBS ACTIVATION REQUESTED TORNADO AND SPECIAL MARINE WARNING NATIONAL WEATHER SERVICE NEW ORLEANS LA 1058 AM CST TUE DEC 18 1990 THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A TORNADO AND SPECIAL MARINE WARNING EFFECTIVE UNTIL NOON CST FOR RESIDENTS IN THE FOLLOWING PARISHES IN SOUTHEAST LOUISIANA ...ST.CHARLES PARISH...NORTHERN ST.TAMMANY PARISH ...SOUTHERN TANGIPAHOA PARISH AND FOR LAKE PONTCHERTRAIN. AT 1017 AM CST THE ST JAMES SHERIFF'S DEPARTMENT REPORTED A TORNADO TOUCHING DOWN BRIEFLY AT LUTCHER KNOKING DOWN POWER LINES AND A SHED. THIS TORNADO IS ASSOCIATED WITH A LINE OF HEAVY SHOWERS MOVING INTO THE WESTERN PROTION OF LAKE PONTCHETRAIN. THE LINE IS MOVING SOUTHEAST AROUND 25 MPH. SHOWERS ARE MOVING NORTHEAST AROUND 45 MPH. IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.
What forecasters said that day
The local office's own words before this tornado 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, Dec 18, 7:14 AM CST, 3 hours 44 minutes before
LAZ006-008-009-181600- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 715 AM CST TUE DEC 18 1990 ...SHOWERS AND A FEW THUNDERSTORMS MOVING ACROSS MOST OF EAST CENTRAL LOUISIANA... RADAR SHOWED AN AREA OF SHOWERS AND A FEW THUNDERSTORMS EXTENDING FROM EUNICE AND OPELOUSAS NORTHEAST TO NATCHEZ MISSISSIPPI...LIVONIA TO NORWOOD...AND DONALDSONVILLE TO KENTWOOD. MOVEMENT WAS SOUTHEAST AT 20 MPH. AS THE SHOWERS AND THUNDERSTORMS MOVE ACROSS THE AREA...THEY WILL PRODUCE GUSTY WINDS...HEAVY RAIN AND DANGEROUS LIGHTNING. THE HEAVY RAIN MAY CAUSE FLOODING OF STREETS...UNDERPASSES AND OTHER LOW LYING AREAS. SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS EAST CENTRAL LOUISIANA FOR: THE NEXT FEW HOURS.
Special weather statement, Dec 18, 8:22 AM CST, 2 hours 36 minutes before
LAZ009-181600- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 820 AM CST TUE DEC 18 1990 ...SHOWERS AND A FEW THUNDERSTORMS WERE APPROACHING BATON ROUGE... RADAR SHOWED A 10 MILE WIDE SOLID LINE OF SHOWERS AND A FEW THUNDERSTORMS FROM SOUTHWEST MISSISSIPPI EXTENDING SOUTHWEST NEAR CLINTON...ACROSS THE NEW ROADS/ST. FRANCIVILLE AREAS TO NEAR NEW IBERIA. MOVEMENT WAS SOUTHEAST ABOUT 25 MPH. THIS LINE WILL MOVE TO BATON ROUGE WITHIN THE NEXT HALF HOUR. AS THESE SHOWERS AND THUNDERSTORMS MOVE ACROSS THE BATON ROUGE METRO FOR THE NEXT TWO TO THREE HOURS...THEY WILL PRODUCE STRONG GUSTY WIND AND BRIEF VERY HEAVY RAIN. THE HEAVY RAIN WILL CAUSE TEMPORARY FLOODING OF STREETS...UNDERPASSES AND OTHER LOW LYING AREAS.
Special weather statement, Dec 18, 9:14 AM CST, 1 hour 44 minutes before
LAZ009-181700- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 915 AM CST TUE DEC 18 1990 ...A COLD FRONT...ACCOMPANIED BY SHOWERS AND A FEW THUNDERSTORMS... MOVED THROUGH THE BATON ROUGE AREA... RADAR SHOWED A 15 MILE WIDE SOLID LINE OF SHOWERS AND A FEW THUNDERSTORMS FROM SOUTHWEST MISSISSIPPI EXTENDING SOUTHWEST ACROSS WATSON AND DENHAM SPRINGS TO JUST EAST OF PLAQUEMINE...CONTINUING SOUTHWEST TO THE COAST. MOVEMENT WAS SOUTHEAST ABOUT 25 MPH. THIS LINE WILL MOVE OUT OF THE BATON ROUGE METRO AREA WITHIN THE NEXT ONE TO TWO HOURS. THE TEMPERATURE WAS 58 DEGREES...WHICH IS A 14 DEGREE DROP FROM THE PREVIOUS HOUR...THE WIND GUSTED TO 35 MPH AND WE RECEIVED LESS THAN A QUARTER OF AN INCH OF RAIN AS THE COLD FRONT MOVED THROUGH. < AS THIS LINE MOVES THROUGH...BRIEF VERY HEAVY RAIN AND WIND GUST 35 TO 40 MPH CAN BE EXPECTED. SOME TEMPORARY FLOODING OF STREETS AND LOW LYING AREAS MAY ALSO OCCUR.
The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 18, 10:58 AM CST | Tornado Warning | LIX | Saint Tammany, Tangipahoa | 62 min |
| Dec 18, 11:31 AM CST | Tornado Warning | LIX | Washington | 29 min |
Nearby
Tornado Warnings in Louisiana, 1990Every tornado warning in 1990Tornadoes 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.