Alert archive / Louisiana / Tornado Warnings in 1990

Tornado Warning 6, NWS New Orleans, LA

March 15, 1990Plaquemines Parish, Louisiana

NWS New Orleans, LA issued this tornado warning at Mar 15, 1990, 3:30 AM CST for Plaquemines Parish, Louisiana. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Mar 15, 1990, 3:30 AM CST (09:30 UTC)
Expired
Mar 15, 1990, 5:30 AM CST
In force
2 hr
Issued by
NWS New Orleans, LA
Area
Whole counties

County Plaquemines 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, 9.5 hours before the alert went out and 79 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-pSkew-T log-p diagram, Slidell Radar S, LA at 00:00Z on 1990-03-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 267 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 00:00Z on 1990-03-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 170 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
267 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
712 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
170 m²/s²
0-3 km storm-relative helicity
194 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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, Mar 14, 11:33 PM CST, 3 hours 57 minutes before
LAZ006-008-009-150630-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
1135 PM CST WED MAR 14 1990

...RAIN AND THUNDERSTORMS MOVING ACROSS PARTS OF EAST CENTRAL
LOUISIANA...

RADAR SHOWED RAIN AND THUNDERSTORMS FROM VICKSBURG MISSISSIPPI
TO ALEXANDRIA...SIMMESPORT AND OPELOUSAS.  PRECIPITATION WAS MOVING
SOUTHEAST AT 20 MPH.

PEOPLE IN EAST CENTRAL LOUISIANA CAN EXPECT PERIODS OF HEAVY RAIN
WITH FLOODING OF STREETS AND OTHER LOW LYING AREAS AND GUSTY WINDS.
Special weather statement, Mar 15, 12:37 AM CST, 2 hours 53 minutes before
LAZ-008-009-150730-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
1230 AM CST THU MAR 15 1990

...THUNDERSTORMS WITH VERY HEAVY RAIN WERE MOVING ACROSS PARTS OF THE
BATON ROUGE METROPOLITAN AREA...

RADAR SHOWED A 10 MILE WIDE SOLID LINE OF THUNDERSTORMS WITH VERY HEAVY
RAIN EXTENDING FROM SOUTHWEST MISSISSIPPI SOUTHWEST ACROSS WEST
FELICIANA AND POINTE COUPEE PARISHES TO LAFAYETTE.  MOVEMENT WAS
SOUTHEAST ABOUT 25 MPH.

PEOPLE THROUGHOUT EAST BATON ROUGE AND SURROUNDING PARISHES CAN EXPECT
FLOODING OF STREETS AND OTHER LOW LYING AREAS AND STRONG AND GUSTY WIND
SHIFTING TO NORTHWEST AS THESE THUNDERSTORMS PASS THROUGH FOR THE NEXT
FEW HOURS.

ELSEWHERE...RADAR SHOWED SCATTERED SHOWERS AND A FEW THUNDERSTORMS FROM
MCCOMB TO BOGALUSA...EXTENDING SOUTHWEST TO NEW IBERIA AND MORGAN CITY.
A SOLID BAND OF MOSTLY LIGHT RAIN AND ISOLATED THUNDERSTORMS
EXTENDED FROM NORTHEAST LOUISIANA SOUTHWEST ACROSS ALEXANDRIA
TO LAKE CHARLES.
Special weather statement, Mar 15, 1:30 AM CST, 2 hours before
LAZ-006-008-009-150830-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
130 AM CST THU MAR 15 1990

...THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUE MOVING ACROSS PARTS OF
THE BATON ROUGE METROPOLITAN AREA...

RADAR SHOWED A 10 MILE WIDE SOLID LINE OF THUNDERSTORMS WITH VERY HEAVY
RAIN EXTENDING FROM SOUTHWEST MISSISSIPPI SOUTHWEST BETWEEN CLINTON AND
GREENSBURG...ACROSS BATON ROUGE TO NEAR PLAQUEMINE...CONTINUING
SOUTHWEST TO THE COAST.  MOVEMENT WAS SOUTHEAST ABOUT 25 MPH.

PEOPLE THROUGHOUT EAST BATON ROUGE AND SURROUNDING PARISHES CAN EXPECT
FLOODING OF STREETS AND OTHER LOW LYING AREAS AND STRONG AND GUSTY WIND
SHIFTING TO NORTHWEST AS THESE THUNDERSTORMS PASS THROUGH FOR THE NEXT
FEW HOURS.

ELSEWHERE...RADAR SHOWED SCATTERED SHOWERS AND A FEW THUNDERSTORMS FROM
MCCOMB TO BOGALUSA...EXTENDING SOUTHWEST TO NEW IBERIA AND MORGAN CITY.
LARGE SOLID AREAS OF MOSTLY LIGHT RAIN AND A FEW THUNDERSTORMS
EXTENDED FROM ?NORTHEAST LOUISIANA SOUTHWEST ACROSS ALEXANDRIA
TO LAKE CHARLES...AND BETWEEN JONESVILLE AND NATZHEZ SOUTH TO
BETWEEN BATON ROUGE AND LAFAYETTE.

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 15, 3:30 AM CSTTornado WarningLIXJefferson, Lafourche2 hr
Mar 15, 3:50 AM CSTTornado WarningLIXSaint Bernard100 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.