Alert archive / Louisiana / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 39, NWS Shreveport, LA

March 17, 1987Jackson Parish, Winn Parish, Louisiana

NWS Shreveport, LA issued this severe thunderstorm warning at Mar 17, 1987, 10:10 AM CST for Jackson Parish, Winn Parish, Louisiana. It was in force for 70 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, 10:10 AM CST (16:10 UTC)
Expired
Mar 17, 1987, 11:20 AM CST
In force
70 min
Issued by
NWS Shreveport, LA
Area
Whole counties

Counties Jackson Parish, LA, Winn 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, 10:30 AM CSTThunderstorm Wind 0Jackson, 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

Longview/Gregg, TX (KGGG), launched 12:00Z, 4.2 hours before the alert went out and 190 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, Longview/Gregg, TX at 12:00Z on 1987-03-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 376 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, Longview/Gregg, TX at 12:00Z on 1987-03-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 274 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
376 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
724 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
274 m²/s²
0-3 km storm-relative helicity
386 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSHV 171613
SVRSHV
LAC049-127-171720-

BULLETIN...IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
1010 AM CST TUE MAR 17 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 1120 AM CST  FOR PEOPLE IN THE FOLLOWING PARISHES IN

NORTH LOUISIANA...JACKSON AND WINN

AT 1010 AM CST THE NATIONAL WEATHER SERVICE RADAR IN SHREVEPORT SHOWED
A STRONG LINE OF THUNDERSTORMS FROM NEAR HOMER LOUISIANA TO NEAR ARCADIA
TO 15 MILES WEST OF JONESBORO TO MOVING EAST OF NATCHITOCHES TO 25
MILES WEST OF ALEXANDRIA ON SOUTHWARD.

THE LINE WAS MOVING EAST AT AN AVERAGE SPEED OF 35 MPH...EXCEPT THAT
PART APPROCHING THE WESTERN PART OF JACKSON AND WESTERN WINN PARISHES
...FOWARD SPEED INCREASING TO 50 MPH.

HIGH DAMAGING WINDS POSSIBLE WITH THAT PART OF THE LINE OVER THE
NEXT HOUR.

TORNADO WATCH REMAINS IN EFFECT ALONG AND AHEAD OF THE LINE OF STRONG
THUNDERSTORMS OVER NORTHCENTRAL AND NORTHEAST LOUISIANA. ISOLATED
STRONG THUNDERSTORMS WERE AHEAD OF THE LINE FROM 30 SOUTHWEST OF
MONROE TO NORTH OF ALEXANDRIA TO SOUTHWEST OF ALEXANDRIA..MOVING
RAPIDLY NORTHEAST.

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 16, 10:50 PM CSTSevere Thunderstorm WarningSHVCaddo80 min
Mar 16, 11:10 PM CSTSevere Thunderstorm WarningSHVDe Soto75 min
Mar 17, 8:00 AM CSTSevere Thunderstorm WarningSHVDe Soto, Red River75 min
Mar 17, 11:20 AM CSTSevere Thunderstorm WarningSHVMadison, Tensas70 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.