Alert archive / Louisiana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 149, NWS Lake Charles, LA

August 30, 1998Calcasieu Parish, Louisiana

NWS Lake Charles, LA issued this severe thunderstorm warning at Aug 30, 1998, 4:39 PM CDT for Calcasieu Parish, Louisiana. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 30, 1998, 4:39 PM CDT (21:39 UTC)
Expired
Aug 30, 1998, 5:40 PM CDT
In force
61 min
Issued by
NWS Lake Charles, LA
Area
Whole counties

County Calcasieu Parish, LA

The radar

The Lake Charles radar (KLCH), 18 km from the middle of the area, began a volume at 21:42 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 9.7 hours before the alert went out and 19 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 1998-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2927 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, Lake Charles Mun, LA at 12:00Z on 1998-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
2927 J/kg
Mixed-layer CIN
-30 J/kg
Mixed-layer LCL
906 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
18 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.

640 
WUUS1 KLCH 302140 RRA
SVRLCH
LAC019-302240-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LAKE CHARLES LA
439 PM CDT SUN AUG 30 1998

THE NATIONAL WEATHER SERVICE IN LAKE CHARLES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CALCASIEU PARISH IN SOUTHWESTERN LOUISIANA

* UNTIL 540 PM CDT

* AT 434 PM CDT... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A SEVERE THUNDERSTORM 23 MILES NORTHWEST OF LAKE CHARLES OR 3
  MILES NORTH OF DEQUINCY MOVING SOUTH AT 5 MPH.

* THIS STORM CAN BE EXPECTED NEAR...
  DEQUINCY BY 510 PM...SULPHUR BY 530 PM.


THIS IS A VERY DANGEROUS STORM. FOR YOUR PROTECTION...SEEK
SHELTER IN A STRONG BUILDING. MOVE TO AN INTERIOR ROOM...SUCH
AS A CLOSET OR BATHROOM ON THE LOWEST FLOOR OF YOUR HOME OR
BUSINESS. DO NOT STAND BY WINDOWS.

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.

NWS Lake Charles, LA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 30, 2:53 PM CDT, 1 hour 46 minutes earlier.

Area forecast discussion, Aug 30, 2:53 PM CDT, 1 hour 46 minutes before
SOUTHEAST TEXAS..SOUTHWEST AND CENTRAL LOUISIANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
253 PM CDT SUN AUG 30 1998

OUTFLOW BOUNDARY FROM THIS MORNINGs MCS NORTH OF THE LCH CWA FIRED
UP A LINE OF THUNDERSTORMS ACROSS EAST CENTRAL LA LATE THIS MORNING.
DOPPLER RADAR ESTIMATED BETWEEN 2 TO 4 INCHES OF RAINFALL IN WESTERN
ST LANDRY PARISH IN LESS THAN AN HOUR...THUS JUSTIFYING THE FFW.
SURFACE TROUGH EXTENDING ACROSS EAST TEXAS AND CENTRAL LA BECOMING
REAL DIFFUSE AND IS EXPECTED TO WASH OUT IN THE NEXT 24H. STILL
THOUGH...EXPECT SCATTERED WIDELY SCATTERED ACTIVITY FOR THE REMAINDER
OF THE AFTERNOON IN THE VICINITY OF THE SURFACE TROUGH AND SHEAR AXIS
AT 50H.

MAIN FORECAST PROBLEM WILL BE EXPECTED DEVELOPMENT OF TROPICAL LOW
IN THE SOUTHWEST GULF OF MEXICO. ALL THREE MODELS...AVN...ETA AND NGM
DEVELOP THE LOW BY MONDAY MORNING. THE ETA IS THE QUICKEST AND THE
AVN A CLOSE SECOND. THE NGM IS CONSIDERABLY SLOWER AND WEAKER WITH
ITS SOLUTION. PREFER THE SLOWER NGM AT THIS TIME BASED ON CLIMATOLOGY
AND THE FACT THAT DEVELOPMENT HAS YET TO OCCUR. IN ADDITION...STEERING
WINDS LIKELY TO BE LIGHT. WINDS WILL GRADUALLY STRENGTHEN THROUGH THE
PERIOD FROM THE EAST. THIS TRAJECTORY CONDUCIVE FOR COASTAL FLOODING
(EKMAN EFFECT) PENDING DEVELOPMENT OF THE LOW. IN THE MEANTIME...WILL
GO WITH LOW CHANCE POPS DURING THE SECOND AND FOURTH PERIODS WITH
ISOLATED EARLY EVENING ACTIVITY. CONVECTIVE DEBRIS FROM ACTIVITY
ALONG THE WESTERN GULF OF MEXICO WILL KEEP CLOUD COVER OVER THE
FORECAST AREA THIS EVENING. THIS WILL HOLD TEMPS UP A BIT THIS EVENING
AS COMPARED TO THE LOWER OUTPUT FROM MOS. WILL USE A COMPROMISE OF
THE AVN AND NGM MOS FOR THE REMAINING PERIODS.

A LOT OF VARIABLES IN THIS FORECAST PACKAGE WITH THE POTENTIAL FOR
BIG CHANGES IN RELATIVELY SHORT AMOUNT OF TIME. WILL NEED TO CLOSELY
MONITOR THE SITUATION.

5

BPT 78/93/74/91 1213
LCH 78/93/74/91 1213
LFT 77/93/74/93 1213
AEX 75/95/71/9`3 2322

In the hours before

Local storm report, Aug 30, 11:59 AM CDT, 4 hours 40 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1159 AM CDT SUN AUG 30 1998

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0800 PM    GIST                      TX   WIND DAMAGE
08/29/98   JASPER                         HIGH WINDS BLEW DOWN TREES,
                                          PHONE LINES, AND POWER LINES
                                          IN GIST. A TREE FELL INTO A
                                          HOUSE. POWER AND PHONE
                                          SERVICE WAS RESTORED BY 630
                                          THIS MORNING.
Local storm report, Aug 30, 2:56 PM CDT, 1 hour 43 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
256 PM CDT SUN AUG 30 1998

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0250 PM    5 W WOODVILLE             TX   0.50 INCH HAIL
08/30/98   TYLER                          MARBLE SIZED HAIL REPORTED
                                          BY KFDM CH 6 METEOROLOGIST
                                          ALONG HIGHWAY 190 WEST OF
                                          WOODVILLE.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 11:51 AM CDTFlash Flood WarningLCHSaint Landry114 min
Aug 30, 3:22 PM CDTSevere Thunderstorm WarningLCHAvoyelles, Rapides63 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 1998Every severe thunderstorm warning in 1998

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; radar from the NEXRAD Level II archive.