Alert archive / Louisiana / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 49, NWS New Orleans, LA

July 11, 1990East Baton Rouge Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Jul 11, 1990, 3:33 PM CDT for East Baton Rouge Parish, Louisiana. It was in force for 27 min.

The area

The counties it named.

The facts

Issued
Jul 11, 1990, 3:33 PM CDT (20:33 UTC)
Expired
Jul 11, 1990, 4:00 PM CDT
In force
27 min
Issued by
NWS New Orleans, LA
Area
Whole counties

County East Baton Rouge 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, 8.6 hours before the alert went out and 138 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 12:00Z on 1990-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1815 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 12:00Z on 1990-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 square meters per square second.1939Sfc1 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
1815 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
787 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KBTR 112033
SVRBTR
LAC033-112100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BATON ROUGE LA
333 PM CDT WED JUL 11 1990
 
THE NATIONAL WEATHER SERVICE IN BATON ROUGE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  400 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN EAST CENTRAL LOUISIANA
 
   ...EAST BATON ROUGE PARISH
 
RADAR INDICATED A SEVERE THUNDERSTORM OVER BATON ROUGE
MOVING NORTH AT 10 MPH.
 
 
 
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.

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, Jul 11, 12:53 PM CDT, 2 hours 40 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-111900-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1240 PM CDT WED JUL 11 1990

AT 1230 PM...A FEW THUNDERSTORMS WITH HEAVY RAIN WERE OCCURRING OVER THE
GREATER NEW ORLEANS AREA. THESE THUNDERSTORMS ARE MOVING VERY SLOWLY TO
THE NORTH THEREFORE...MORTORIST CAN EXPECT POOR DRIVING CONDITIONS AS
BRIEF FLOODING OF STREETS AND LOW LYING AREAS MAY OCCUR ALONG WITH
DANGEROUS LIGHTNING AND STRONG GUSTY WINDS. BOATERS ON AREA LAKES SHOULD
ALSO EXERCISE CAUTION AS THESE STORMS ARE VERY LIKELY TO CAUSE HIGHER
WAVES.

A COUPLE OF OTHER THUNDRSTORMS WITH HEAVY RAIN WERE BETWEEN GRAND ISLE
AND HOUMA. MOSTLY SHOWERS WERE OCCURRING THE BATON ROUGE AREA.

A CLUSTER OF THUNDERSTORMS WITH HEAVY RAIN CONTINUED ACROSS SOUTHEAST
MISSISSIPPI FROM 15 MILES NORTH OF GULFPORT EAST INTO SOUTHWEST ALABAMA
TO 25 MILES NORTHWEST OF MOBILE
THE THUNDERSTORM ACTIVITY WAS MOVING SLOWLY TO THE NORTH.
Special weather statement, Jul 11, 1:36 PM CDT, 1 hour 57 minutes before
LAZ006-008-009-112130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
135 PM CDT WED JUL 11 1990

...THUNDERSTORMS WITH HEAVY RAIN MOVING ACROSS PARTS OF EAST CENTRAL
LOUISIANA...

RADAR SHOWED THUNDERSTORMS WITH HEAVY RAIN FROM DONALDSONVILLE AND
WHITE CASTLE NORTH ACROSS BATON ROUGE AND PORT ALLEN TO MORGANZA AND
CLINTON AND FROM GROSSE TETE TO OPELOUSAS.  MOVEMENT WAS NORTH AT
10 MPH.

THUNDERSTORMS WILL PRODUCE STRONG GUS2TY WINDS...VERY HEAVY RAIN WITH
TEMPORARY FLOODING OF STREETS AND LOW LYING AREAS...DANGEROUS LIGHTNING
WITH HAIL POSSIBLE FOR THE NEXT FEW HOURS.
Special weather statement, Jul 11, 1:52 PM CDT, 1 hour 41 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-112000-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
140 PM CDT WED JUL 11 1990

AT 130 PM...A FEW THUNDERSTORMS WITH HEAVY RAIN CONTINUED BETWEEN THE
GREATER NEW ORLEANS AREA AND THIBODAUX. THESE THUNDERSTORMS ARE MOVING
SLOW THE NORTHWEST THEREFORE...MORTORIST CAN EXPECT POOR DRIVING
CONDITIONS AS BRIEF FLOODING OF STREETS AND LOW LYING AREAS MAY OCCUR
ALONG WITH DANGEROUS LIGHTNING AND STRONG GUSTY WINDS. BOATERS ON AREA
LAKES SHOULD ALSO EXERCISE CAUTION AS THESE STORMS ARE VERY LIKELY TO
CAUSE HIGHER WAVES.

SCATTERED SHOWERS AND THUNDRSTORMS...A FEW WITH HEAVY RAIN...ALSO
CONTINUED GENERALLY BETWEEN BATON ROUGE AND LAFAYETTE.

A CLUSTER OF THUNDERSTORMS WITH HEAVY RAIN CONTINUED OVER SOUTHEAST
MISSISSIPPI 20 MILES SOUTHEAST OF HATTIESBURG. AND ANOTHER CLUSTER OF
THUNDERSTORMS WITH HEAVY RAIN CONTINUED OVER SOUTHWEST ALABAMA
BETWEEN 30 MILES AND 80 MILERS NORTH OF MOBILE.

MOVEMENT WAS TO THE NORTH AND NORTHWEST AT 5 TO 10 MILES AN HOUR.
Special weather statement, Jul 11, 2:07 PM CDT, 1 hour 26 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-112100-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
140 PM CDT WED JUL 11 1990

AT 130 PM...A FEW THUNDERSTORMS WITH HEAVY RAIN CONTINUED BETWEEN THE
GREATER NEW ORLEANS AREA AND THIBODAUX. THESE THUNDERSTORMS ARE MOVING
SLOWLY TO THE NORTHWEST. MOTORIST CAN EXPECT POOR DRIVING CONDITIONS
AS BRIEF FLOODING OF STREETS AND LOW LYING AREAS MAY OCCUR ALONG
WITH DANGEROUS LIGHTNING AND STRONG GUSTY WINDS. BOATERS ON AREA
LAKES SHOULD ALSO EXERCISE CAUTION AS THESE STORMS ARE VERY LIKELY TO
CAUSE HIGHER WAVES.

SCATTERED SHOWERS AND THUNDRSTORMS...A FEW WITH HEAVY RAIN...ALSO
CONTINUED GENERALLY BETWEEN BATON ROUGE AND LAFAYETTE.

A CLUSTER OF THUNDERSTORMS WITH HEAVY RAIN CONTINUED OVER SOUTHEAST
MISSISSIPPI 20 MILES SOUTHEAST OF HATTIESBURG. AND ANOTHER CLUSTER OF
THUNDERSTORMS WITH HEAVY RAIN CONTINUED OVER SOUTHWEST ALABAMA
BETWEEN 30 MILES AND 80 MILES NsORTH OF MOBILE.

MOVEMENT WAS TO THE NORTH AND NORTHWEST AT 5 TO 10 MILES AN HOUR.
Special weather statement, Jul 11, 2:50 PM CDT, 43 minutes before
LAZ006-008-009-112200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
250 PM CDT WED JUL 11 1990

...STRONG THUNDERSTORMS WITH HEAVY RAIN MOVING ACROSS PARTS OF EAST
CENTRAL LOUISIANA...

RADAR SHOWED STRONG THUNDERSTORMS WITH HEAVY RAIN FROM WHITE CASTLE...
DONALDSONVILLE AND LAKE MAUREPAS NORTH ACROSS GROSSE TETE AND DENHAM
SPRINGS TO ANGOLA AND CLINTON AND FROM PORT BARRE AND MORGANZA TO
MARKSVILLE AND SIMMESPORT.  MOVEMENT WAS NORTH AT 10 MPH.

THUNDERSTORMS WILL PRODUCE STRONG GUSTY WINDS...VERY HEAVY RAIN WITH
TEMPORARY FLOODING OF STREETS AND LOW LYING AREAS...DANGEROUS LIGHTNING
AND POSSIBLY SOME HAIL FOR THE NEXT FEW HOURS.
Special weather statement, Jul 11, 2:53 PM CDT, 40 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-112100-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
250 PM CDT WED JUL 11 1990

AT 230 PM...A FEW THUNDERSTORMS WITH HEAVY RAIN CONTINUED BETWEEN THE
GREATER NEW ORLEANS AREA AND AVERY ISLAND. THESE THUNDERSTORMS ARE
MOVING SLOWLY NORTHWEST. MOTORIST CAN EXPECT POOR DRIVING CONDITIONS
AS BRIEF FLOODING OF STREETS AND LOW LYING AREAS MAY OCCUR...AS WELL AS
DANGEROUS LIGHTNING AND STRONG GUSTY WIND. BOATERS ON AREA LAKES
SHOULD ALSO EXERCISE CAUTION AS THESE THUNDERSTORM WINDS WILL LIKELY
CAUSE ROUGH SEAS.

SCATTERED SHOWERS AND THUNDERSTORMS...A FEW WITH HEAVY RAIN...ALSO WERE
OCCURRING SOUTHEAST OF LAFAYETTE...BETWEEN SLIDELL AND COVINGTON...AND
ALONG THE NORTHERN HALF OF THE MISSISSIPPI RIVER DELTA.

A CLUSTER OF STRONG THUNDERSTORMS WITH HEAVY RAIN CONTINUED OVER
SOUTHWEST ALABAMA.

ELSEWHERE...SCATTERED SHOWERS AND THUNDERSTORMS SPREAD ACROSS SOUTH
LOUISIANA AND THE COASTAL WATERS EASTWARD ACROSS SOUTHEAST MISSISSIPPI
AND INTO SOUTHWEST ALABAMA.

MOVEMENT WAS TOWARDS THE NORTHWEST AT 5 TO 10 MILES AN HOUR.

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.