Alert archive / Louisiana / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 40, NWS Lake Charles, LA

March 13, 1999Vernon Parish, Louisiana

NWS Lake Charles, LA issued this severe thunderstorm warning at Mar 13, 1999, 1:01 AM CST for Vernon Parish, Louisiana. It was in force for 64 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 13, 1999, 1:01 AM CST (07:01 UTC)
Expired: Mar 13, 1999, 2:05 AM CST
In force: 64 min
Issued by: NWS Lake Charles, LA
Area: Whole counties

County Vernon Parish, LA

The radar

The Ft Polk radar (KPOE), 20 km from the middle of the area, began a volume at 07:00 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.

What was reported inside it

Time	Report	Where	Remark
Mar 13, 1:22 AM CST	Hail 1.75	Anacoco, 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Mar 12, 10:30 PM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 7.0 hours before the alert went out and 110 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 892 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 549 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 213 m²/s²
0-3 km storm-relative helicity: 327 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 9.8

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Mar 12, 8:04 PM CST, 4 hours 57 minutes earlier.

Area forecast discussion, Mar 12, 8:04 PM CST, 4 hours 57 minutes before

SOUTHWEST...CENTRAL LOUISIANA AND SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
804 PM CST FRI MAR 12 1999

850 MB UPPER LEVEL CHART INDICATES JET WITH 35 TO 50 KNOT ALONG
SABINE RIVER THIS EVENING. MOISTURE CONTINUING TO POOL JUST WEST
OF SE TX COUNTY WARNING AREA WITH DEWPOINTS IN THE MID TO UPPER
60S. APPEARS TO BE DECENT LOW LEVEL CONVERGENCE WITH OPPOSING
WINDS MEETING NORTHWEST OF LUFKIN TO NEAR COLLEGE STATION TO
NEAR HONDO TX. SATELLITE AND RADAR INDICATING SUPERCELL DEVELOPMENT
ALONG SOUTHWEST FLANK OF THE CONVERGENCE LINE NEAR A 970 MB SFC
LOW NEAR KCOT. HOUSTON RADAR INDICATED A FEW CELLS DEVELOPING BUT
AT THIS MOMENT JUST IN BEGINNING STAGE. THEIR IS DEFINITELY A CAP
TONIGHT IN OUR CWA AREA BETWEEN 710 MB TO 640 MB. IT MAY TAKE SOME
TIME FOR DEVELOPMENT...BUT ALL THE INGREDIENTS ARE PRESENT FOR
SCATTERED SUPERCELL DEVELOPMENT TO OCCUR IN TORNADO WATCH AREA OVER SE
TX IN THE NEXT FEW HOURS. HEAVY RAIN A THREAT WITH PWS RUNNING
1.50 INCHES. COASTAL FLOOD WATCH LOOKS OK AS SE TO EAST FLOW
CONTINUES AT 15 KNOTS ALONG COASTAL AREA. WILL CONTINUE WITH
CURRENT PACKAGE. 06

BPT TA 067/075 045/060 040 6800
LCH TA 065/075 047/062 040 6800
LFT TA 063/072 050/057 040 3840
AEX TA 057/068 045/055 036 6820

AFTERNOON DISCUSSION 230 PM

BOTH THE MAPS GUIDANCE AND THE LAGRANGIAN TRAJECTORY GUIDANCE
MAXIMIZE THE UPDRAFT POTENTIAL (CAPE) AND THE ROTATIONAL POTENTIAL
(HELICITY) ACROSS THE EASTERN TEXAS COUNTIES BY EARLY TOMORROW
MORNING. THE MAIN DYNAMIC PLAYERS APPEAR TO BE THE BRANCHING CIRRUS-
LEVEL WESTERLIES AND THE EKMAN-LAYER INERTIAL JET (LOW LEVEL JET).
DEEPENING ISALLOBARS ACROSS LOUISIANA TOMORROW MORNING SUGGEST
THAT THIS CONVECTIVE EVENT WILL MARCH EASTWARD UNIMPEDED TROUGH THE
FCST AREA.

FROM A SATELLITE PERSPECTIVE...MY EYES FOCUS-IN ON THE CUT-OFF LOW
CURRENTLY OVER NEW MEXICO. THE MAPS GUIDANCE FORECASTS THIS CUT-OFF TO
TREK EAST-SOUTHEAST AND DEEPEN. A VIGOROUS BAROCLINIC ENERGY
CONVERSION IS ANTICIPATED AS THIS DEEP COLD POOL OF AIR OVER TEXAS
JUXTAPOSES THE DEEP WARM POOL OF AIR ACROSS THE REMAINING SOUTHEAST
UNITED STATES.

WHEN THE FIREWORKS END...THE TROPOPAUSE LEVEL WILL SINK TO THE
500 MB LEVEL...QUITE A TROPOPAUSE FOLD.

AFTER TALKING WITH SLIDELL...WE AGREE THAT A COASTAL FLOOD WATCH WILL
BE IN-EFFECT FOR TONIGHT. EASTERLY WINDS ACROSS THE COASTAL WATERS
ARE AROUND 20 KT. WITH TIDES RUNNING ABOVE NORMAL...SOME PILING-UP
OF THE WATER IS EXPECTED ALONG THE COAST. THE FLASH FLOOD WATCH
REMAINS IN-EFFECT.

21

BPT TA 067/075 045/060 040 6800
LCH TA 065/075 047/062 040 6800
LFT TA 063/072 050/057 040 3840
AEX TA 057/068 045/055 036 6820

In the hours before

Local storm report, Mar 12, 9:55 PM CST, 3 hours 6 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
955 PM CST FRI MAR 12 1999

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

0940 PM    CHESTER                   TX   1.00 INCH HAIL
03/12/99   TYLER

Local storm report, Mar 12, 11:07 PM CST, 1 hour 54 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1107 PM CST FRI MAR 12 1999

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

1035 PM                              TX   0.75 INCH HAIL
03/12/99   TYLER

Local storm report, Mar 12, 11:26 PM CST, 1 hour 35 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1126 PM CST FRI MAR 12 1999

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

1035 PM    WOODVILLE                 TX   WIND DAMAGE
03/12/99   TYLER                          POWERLINES DOWN

Local storm report, Mar 12, 11:44 PM CST, 1 hour 17 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1144 PM CST FRI MAR 12 1999

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

1132 PM    JASPER                    TX   0.75 INCH HAIL
03/12/99   JASPER

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 13, 8:02 AM CST	Tornado Warning	LCH	Evangeline	63 min
Mar 13, 8:22 AM CST	Tornado Warning	LCH	Saint Landry	33 min
Mar 13, 11:33 AM CST	Tornado Warning	LCH	Vermilion	47 min
Mar 13, 12:34 PM CST	Tornado Warning	LCH	Saint Martin	46 min
Mar 12, 9:28 PM CST	Severe Thunderstorm Warning	LCH	Tyler	62 min
Mar 12, 10:04 PM CST	Tornado Warning	LCH	Tyler	66 min
Mar 12, 10:54 PM CST	Tornado Warning	LCH	Jasper	61 min
Mar 12, 11:43 PM CST	Tornado Warning	LCH	Newton	62 min
Mar 13, 12:25 AM CST	Flash Flood Warning	LCH	Jasper, Newton	2 hr
Mar 13, 12:25 AM CST	Flash Flood Warning	LCH	Tyler	2 hr
Mar 13, 2:15 AM CST	Flash Flood Warning	LCH	Jasper, Newton	3 hr
Mar 13, 2:15 AM CST	Flash Flood Warning	LCH	Tyler	3 hr
Mar 13, 2:26 AM CST	Tornado Warning	LCH	Tyler	64 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 1999 Every severe thunderstorm warning in 1999

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; radar from the NEXRAD Level II archive.