Alert archive / Louisiana / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 13, NWS New Orleans, LA

March 17, 1987Iberia Parish, Saint Martin Parish, St. Mary Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Mar 17, 1987, 4:31 PM CST for Iberia Parish, Saint Martin Parish, St. Mary Parish, Louisiana. It was in force for 59 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
Mar 17, 1987, 4:31 PM CST (22:31 UTC)
Expired
Mar 17, 1987, 5:30 PM CST
In force
59 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

TimeReportWhereRemark
Mar 17, 4:40 PM CSTThunderstorm Wind 0St. 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 12:00Z, 10.5 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.

Skew-T log-pSkew-T log-p diagram, Lake Charles Mun, LA at 12:00Z on 1987-03-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 133 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 12:00Z on 1987-03-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 544 square meters per square second.19395878Sfc1 km3 km6 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
133 J/kg
Mixed-layer CIN
-270 J/kg
Mixed-layer LCL
658 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
544 m²/s²
0-3 km storm-relative helicity
810 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KNEW 172231
SVRNEW
LAC045-099-101-172330-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
431 PM CST TUE MAR 17 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL  530 PM CST FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTHEAST LOUISIANA
          ...IBERIA...ST.MARTIN...ST.MARY
 
RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS EXTENDING NORTH TO
SOUTH OVER THE EXTREME WEST PORTION OF ST MARTIN AND IBERIA PARISHES
AND MOVING EAST AT 20 MPH WITH INDIVIDUALS CELLS MOVING NORTHEAST
AT 40 MPH.
 
A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA.  REMEMBER
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.  REMAIN CALM BUT BE ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS.
 
WHEN THUNDERSTORMS ARE OCCURRING...PEOPLE SHOULD MOVE INSIDE A
STRONG BUILDING.  DO NOT STAND BY WINDOWS.  DON'T USE TELEPHONES
OR ELECTRICAL APPLIANCES UNLESS IN AN EMERGENCY UNTIL THE STORM
HAS PASSED.  MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS.
 
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, Mar 17, 12:40 PM CST, 3 hours 51 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1237 PM CST TUE MAR 17 1987

...A TORNADO WATCH IS IN EFFECT FOR ALL OF SOUTHEAST LOUISIANA UNTIL
   4 PM CST THIS TUESDAY AFTERNOON...

SCATTERED THUNDERSTORMS...A FEW STRONG...WERE OCCURRING ACROSS CENTRAL
LOUISIANA AND EXTENDED INTO SOUTHWEST MISSISSIPPI. THE THUNDERSTORMS
WERE OCCURRING FROM MC COMB MISSISSIPPI TO JACKSON MISSISSIPPI WEST
ACROSS THE MISSISSIPPI RIVER TO BETWEEN ALEXANDRIA AND SIMMESPORT
LOUISIANA.

THESE THUNDERSTORMS ARE CAPABLE OF PRODUCING STRONG GUSTY WINDS...
DANGEROUS LIGHTNING...VERY HEAVY RAIN AND POSSIBLY SOME SMALL HAIL AS
THEY MOVE RAPIDLY NORTHEAST AT 50 MILES AN HOUR.

PERSONS IN THE WATCH AREA SHOULD REMAIN ALERT AND TAKE SHELTER IF
THREATENING WEATHER IS SIGHTED.
WIDELY SCATTERED SHOWERS WERE OCCURRING OVER SOUTHEAST LOUISIANA
FROM SIMMESPORT SOUTH TO THE GULF COAST NEAR MORGAN CITY.
Special weather statement, Mar 17, 1:29 PM CST, 3 hours 2 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
130 PM CST TUE MAR 17 1987

...A TORNADO WATCH REMAINS IN EFFECT UNTIL 4PM THIS AFTERNOON FOR ALL
OF EAST CENTRAL LOUISIANA...

RADAR SHOWED STRONG THUNDERSTORMS CONTINUED ACROSS CATAHOULA PARISH
NEAR HARRISONBURG TO MARKSVILLE IN AVOYELLES PARISH TO EUNICE LOUISIANA
IN ST LANDRY PARISH.  DUE TO THE SLOW MOVEMENT OF THIS AREA...HEAVY RAIN
WITH SOME FLOODING WILL OCCURE IN THE MENTIONED PARISHES.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES
AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.  PEOPLE IN
THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER
CONDITIONS AND LISTEN FOR LATER' STATEMENTS AND POSSIBLE WARNINGS.
Special weather statement, Mar 17, 1:37 PM CST, 2 hours 54 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE NEW ORLEANS LA
137 PM CST TUE MAR 17 1987

...A TORNADO WATCH IS IN EFFECT FOR ALL OF SOUTHEAST LOUISIANA UNTIL
   4 PM CST THIS TUESDAY AFTERNOON...

SCATTERED THUNDERSTORMS...A FEW WITH HEAVY RAIN...WERE OCCURRING ACROSS
SOUTH CENTRAL AND SOUTHWEST MISSISSIPPI AND EXTENDED INTO A SMALL PART
OF EAST CENTRAL LOUISIANA. THE THUNDERSTORMS WERE OCCURRING FROM JACKSON
TO MCCOMB MISSISSIPPI WEST ACROSS THE MISSISSIPPI RIVER TO BETWEEN
ALEXANDRIA AND SIMMESPORT LOUISIANA.

THE THUNDERSTORMS ARE CAPABLE OF PRODUCING STRONG GUSTY WINDS..DANGEROUS
LIGHTNING..VERY HEAVY RAIN AND POSSIBLY SOME SMALL HAIL.  THE STORMS
ARE MOVING RAPIDLY NORTHEAST AT 50 MILES AN HOUR.

PERSONS IN THE WATCH AREA SHOULD REMAIN ALERT AND TAKE SHELTER IF
THREATENING WEATHER IS SIGHTED.
<

ONLY WIDELY SCATTERED SHOWERS WERE OCCURRING OVER PARTS OF SOUTHEAST
AND SOUTH CENTRAL LOUISIAN5A AT THIS TIME.  HOWEVER...THUNDERSTORMS
ARE EXPECTED TO DEVELOP OVER PARTS OF SOUTHEAST LOUISIANA WITHIN THE
NEXT COUPLE OF HOURS.
Special weather statement, Mar 17, 2:44 PM CST, 1 hour 47 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
245 PM CST TUE MAR 17 1987

...A TORNADO WATCH REMAINS IN EFFECT UNTIL 4PM THIS AFTERNOON FOR ALL
OF EAST CENTRAL LOUISIANA...

RADAR SHOWED STRONG THUNDERSTORMS FROM CONCORDIA PARISH SOUTH ACROSS
AVOYELLES INTO ST LANDRY PARISH.  OTHER STRONG THUNDERSTORMS WERE
FROM DOWNTOWN BATON ROUGE NORTH TO CLINTON.  THE STRONG THUNDERSTORMS
WILL PRODUCE HEAVY RAINS CAUSING SOME FLOODING OF LOW AREAS ACROSS THE
ABOVE PARISHES DURING THE AFTERNOON.  SMALL HAIL WAS REPORTED IN THE
SOUTHERN PART OF EAST BATON ROUGE PARISH DURING THE PAST HOUR.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES
AND SEVERE THUNDERSTORMsS IN AND CLOSE TO THE WATCH AREA.  PEOPLE IN
THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER
CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS.
Special weather statement, Mar 17, 3:00 PM CST, 1 hour 31 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
330 PM CST TUE MAR 17 1987

...STRONG SOUTHEAST WINDS WILL CONTINUE TO PRODUCE TIDES WELL
   ABOVE NORMAL ALONG THE LOUISIANA COAST...

A STRONG LOW PRESSURE SYSTEM..CENTERED OVER THE CENTRAL PLAIN
STATES..IN COMBINATION WITH A HIGH PRESSURE SYSTEM..OVER THE
ATLANTIC SEABOARD..IS PRODUCING STRONG SOUTH AND SOUTHEAST WINDS
WINDS OVER THE GULF OF MEXICO.  WINDS OF 25 TO 35 MPH WITH HIGHER
GUSTS ARE PRODUCING 8 TO 12 FOOT SEAS OVER THE LOUISIANA COASTAL
WATERS..AND TIDES OF 2 TO 4 FEET ABOVE NORMAL.  RISING WATER
HAS PRODUCED SOME MINOR FLOODING IN SOUTHEAST ORLEANS PARISH AND
ALONG THE INTERCOASTAL WATERWAY.

STRONG SOUTHEAST WINDS ARE EXPECTED TO PERSIST THROUGH TONIGHT AND
MAY CAUSE TIDES TO RISE..IN SOME AREAS..AS MUCH AS 4 FEET ABOVE
NORMAL BY WEDNESDAY MORNING.
<
RESIDENTS ALONG THE SOUTHEAST AND SOUTH LOUISIANA COASTS AND ALL
MARINE INTERESTS SHOULD MONITOR FUTURE WEATHER FORECASTS FOR
ADDITIONAL INFORMATION.
Special weather statement, Mar 17, 4:04 PM CST, 27 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BATON ROUGE LA
405 PM CST TUE MAR 17 1987

...A TORNADO WATCH IS IN EFFECT UNTIL 10 PM THIS EVENING FOR ALL
OF EAST CENTRAL LOUISIANA EXCEPT CATAHOULA PARISH...

RADARS SHOWED A 25 MILE WIDE BAND OF STRONG THUNDERSTORMS FROM THE
ACME AREA IN SOUTHERN CONCORDIA PARISH SOUTH ACROSS PARTS OF POINTE
COUPEE...AVOYELLES AND INTO ST LANDRY PARISH. THE THUNDERSTORMS WILL
PRODUCE HEAVY RAINS CAUSING SOME FLOODING OF LOW AREAS IN THE ABOVE
PARISHES DURING THE AFTERNOON.  THUNDERSTORMS WILL CONTINUE TO MOVE
SLOWLY EASTWARD INTO THE EVENING HOURS.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR TORNADOES
AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.  PEOPLE IN
THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER
CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS.

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 17, 9:50 AM CSTSevere Thunderstorm WarningLIXIberville, Pointe Coupee40 min
Mar 17, 10:05 AM CSTSevere Thunderstorm WarningLIXWest Baton Rouge40 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 1987Every severe thunderstorm warning in 1987

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.