Alert archive / Louisiana / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 21, NWS New Orleans, LA

May 21, 1990East Feliciana Parish, West Feliciana Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at May 21, 1990, 2:51 PM CDT for East Feliciana Parish, West Feliciana Parish, Louisiana. It was in force for 69 min.

The area

The counties it named.

The facts

Issued
May 21, 1990, 2:51 PM CDT (19:51 UTC)
Expired
May 21, 1990, 4:00 PM CDT
In force
69 min
Issued by
NWS New Orleans, LA
Area
Whole counties

Counties East Feliciana Parish, LA, West Feliciana 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, 7.9 hours before the alert went out and 162 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 1990-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2055 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 1990-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 square meters per square second.193958Sfc1 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
2055 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
807 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.4

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KBTR 211951
SVRBTR
LAC037-091-125-212100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BATON ROUGE LA
251 PM CDT MON MAY 21 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 FELICIANA PARISH...ST.HELENA PARISH...WEST FELICIANA PARISH
 
RADAR AT 255 PM CDT SHOWED A LINE OF STRONG THUNDERSTORMS ALONG THE
LOUISIANA/MISSISSIPPI BORDER FROM NORTH OF ANGOLA EAST TO NORTH OF
KENTWOOD.  THIS LINE IS MOVING SOUTH AT 25 TO 30 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, May 21, 12:49 PM CDT, 2 hours 2 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-211900-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1235 PM CDT MON MAY 21 1990

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON
PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT...

AN AREA OF THUNDERSTORMS WERE OCCURRING OVER SOUTHERN MISSISSIPPI
BETWEEN JACKSON AND NATCHEZ EXTENDING EAST TO NEAR MERIDIAN. THE
AREA WAS MOVING SOUTH AT 25 MILES AN HOUR.

SCATTERED PATCHES OF LIGHT RAIN AND SHOWERS WERE ALSO OCCURRING OVER
EXTREME SOUTHEAST MISSISSIPPI AND SOUTHWEST WEST ALABAMA.

THERE ARE NO THUNDERSTORMS OVER SOUTHEAST LOUISIANA AT THE PRESENT
TIME HOWEVER THUNDERSTORM ACTIVITY MAY DEVELOP A*CROSS THE AREA THIS
AFTERNOON. THESE THUNDERSTORMS COULD BE CAPABLE OF PRODUCING STONG
GUSTY WINDS...FREQUENT LIGHTNING...POSSIBE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 12:53 PM CDT, 1 hour 58 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-211900-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1235 PM CDT MON MAY 21 1990

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON
PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT...

AN AREA OF THUNDERSTORMS WERE OCCURRING OVER SOUTHERN MISSISSIPPI
BETWEEN JACKSON AND NATCHEZ EXTENDING EAST TO NEAR MERIDIAN. THE
AREA WAS MOVING SOUTH AT 25 MILES AN HOUR.

SCATTERED PATCHES OF LIGHT RAIN AND SHOWERS WERE ALSO OCCURRING OVER
EXTREME SOUTHEAST MISSISSIPPI AND SOUTHWEST ALABAMA.

THERE ARE NO THUNDERSTORMS OVER SOUTHEAST LOUISIANA AT THE PRESENT
TIME HOWEVER THUNDERSTORM ACTIVITY MAY DEVELOP AC/ROSS THE AREA THIS
AFTERNOON. THESE THUNDERSTORMS COULD BE CAPABLE OF PRODUCING STRONG
GUSTY WINDS...FREQUENT LIGHTNING...POSSIBLE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 1:55 PM CDT, 56 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-212000-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
145 PM CDT MON MAY 21 1990

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON
PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT...

A LINE OF THUNDERSTORMS WAS OCCURRING FROM SOUTH OF MERIDIAN EXTENDING
SOUTHWEST TO BETWEEN HAZELHURST AND MC COMB AND CONTINUING SOUTHWEST TO
BETWEEN NATCHEZ MISSISSIPPI AND SIMMESPORT LOUISIANA.

OTHERWISE PATCHES OF LIGHT RAIN WITH SHOWERS AND THUNDESTORMS CONTINUED
ACROSS SOUTHERN MISSISSIPPI AND SOUTHWEST ALABAMA.

THERE IS NO THUNDERSTORM ACTIVITY OVER SOUTHEAST LOUISIANA HOWEVER
PRECIPITATION IS DEVELOPING NEAR THE AREA AND THE THUNDERSTORM ACTIVITY
OVER MISSISSIPPI IS SOUTH. THUNDERSTORMS ARE POSSIBLE AND WILL BE
CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING...POSSIBLE
HAIL AND HEAVY RAINS.
Special weather statement, May 21, 1:59 PM CDT, 52 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-212000-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
145 PM CDT MON MAY 21 1990

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON
PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT...

A LINE OF THUNDERSTORMS WAS OCCURRING FROM SOUTH OF MERIDIAN EXTENDING
SOUTHWEST TO BETWEEN HAZELHURST AND MC COMB AND CONTINUING SOUTHWEST TO
BETWEEN NATCHEZ MISSISSIPPI AND SIMMESPORT LOUISIANA.

OTHERWISE PATCHES OF LIGHT RAIN WITH SHOWERS AND THUNDESTORMS CONTINUED
ACROSS SOUTHERN MISSISSIPPI AND SOUTHWEST ALABAMA.

THERE IS NO THUNDERSTORM ACTIVITY OVER SOUTHEAST LOUISIANA HOWEVER
PRECIPITATION IS DEVELOPING NEAR THE AREA AND THE THUNDERSTORM ACTIVITY
OVER MISSISSIPPI IS MOVING SOUTH. THUNDERSTORMS ARE POSSIBLE AND WILL
BE CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING...
POSSIBLE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 2:31 PM CDT, 20 minutes before
LAZ009-212030-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
230 PM CDT MON MAY 21 1990

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 5 PM CDT FOR EAST
CENTRAL LOUISIANA EXCEPT FOR ASCENSION PARISH...

RADAR SHOWED AN AREA OF THUNDERSTORMS EXTENDING EAST TO WEST ALONG THE
MISSISSIPPI/LOUISIANA BORDER FROM NORTHEAST OF KENTWOOD WESTWARD NORTH
OF ANGOLA CONTINUING INTO LOUISIANA NEAR JUST NORTH OF MARKSVILLE.  THE
THUNDERSTORMS WERE MOVING SOUTHWARD AROUND 25 MPH.

THESE THUNDERSTORMS WILL PRODUCE STRONG GUSTY WINDS AND SMALL HAIL AS
THEY MOVE INTO EAST AND WEST FELICIANA AND ST. HELENA PARISHES DURING
THE NEXT HOUR.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE
FOR SEVERE THUNDERSTORMS IN...AND CLOSE TO...THE WATCH AREA.  PERSONS
IN EAST CENTRAL LOUISIANA SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND/OR WARNINGS.

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 12:31 PM CDTSevere Thunderstorm WarningLIXCatahoula, Concordia74 min
May 21, 2:42 PM CDTSevere Thunderstorm WarningLIXTangipahoa, Washington63 min
May 21, 2:51 PM CDTSevere Thunderstorm WarningLIXSaint Helena69 min
May 21, 4:11 PM CDTSevere Thunderstorm WarningLIXSaint Bernard49 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.