Alert archive / Texas / Tornado Warnings in 1999

Tornado Warning 53, NWS Shreveport, LA

May 4, 1999Upshur County, Texas

NWS Shreveport, LA issued this tornado warning at May 4, 1999, 2:20 PM CDT for Upshur County, Texas. It was in force for 40 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: May 4, 1999, 2:20 PM CDT (19:20 UTC)
Expired: May 4, 1999, 3:00 PM CDT
In force: 40 min
Issued by: NWS Shreveport, LA
Area: Whole counties

County Upshur County, TX

The radar

The Shreveport radar (KSHV), 108 km from the middle of the area, began a volume at 19:20 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

Shreveport, LA (KSHV), launched 12:00Z, 7.3 hours before the alert went out and 115 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: 1116 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 498 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 275 m²/s²
0-3 km storm-relative helicity: 392 m²/s²
Significant tornado parameter: 2.0
Supercell composite: 12.5

Open this sounding in Storm Lab

The text

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

999 
WFUS1 KSHV 041922 RRA
TORSHV
TXC459-042000-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
220 PM CDT TUE MAY 4 1999

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
  UPSHUR COUNTY IN NORTHEAST TEXAS

* UNTIL 300 PM CDT

* AT 220 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 9 MILES WEST OF
  GILMER...MOVING NORTHEAST AT 50 MPH.

TORNADOES ASSOCIATED WITH THIS TYPE OF THUNDERSTORM USUALLY OCCUR ON
THE EAST TO SOUTH PART OF THE STORM.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN SHREVEPORT.

What forecasters said that day

The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Shreveport, LA wrote its last area forecast discussion before this tornado warning went out at May 4, 10:00 AM CDT, 4 hours 20 minutes earlier.

Area forecast discussion, May 4, 10:00 AM CDT, 4 hours 20 minutes before

FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
1000 AM CDT TUE MAY 4 1999

CURRENT FORECAST STILL ON TRACK. LATEST ETA RUN SHOWS MID LEVEL JET
KICKING IN AROUND 18Z OVER CWA. ONLY SAVING GRACE AT THIS TIME IS
THE CLOUD COVER...WHICH IS HELPING TO HOLD STABILITY DOWN A TAD AS
WELL AS SURFACE WIND BELOW WIND ADVISORY THRESHOLD. THIS MAY CHANGE
IF LARGE UNANTICIPATED BREAKS OCCUR. BUT UNTIL ANY UNFORESEEN CHANGES
OCCUR..FORECAST CAN CONTINUE AS IS.

14

In the hours before

Special weather statement, May 4, 10:10 AM CDT, 4 hours 10 minutes before

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-041630-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
1010 AM CDT TUE MAY 4 1999

...AN OUTBREAK OF SEVERE WEATHER COULD AFFECT MOST OF THE THE
FOUR STATE REGION TODAY AND TONIGHT...

THERE IS HIGH RISK OF SEVERE THUNDERSTORMS TODAY AND TONIGHT FOR ALL
OF NORTHEAST TEXAS...NORTH LOUISIANA...SOUTHERN ARKANSAS AND
MC CURTAIN COUNTY IN SOUTHEAST OKLAHOMA.  THE AIRMASS ACROSS THE
AREA IS MOIST AND UNSTABLE.  A STRONG UPPER LEVEL STORM SYSTEM WILL
MOVE ACROSS THE CENTRAL PLAINS TODAY AND TONIGHT.  THUNDERSTORMS
WILL LIKELY DEVELOP ACROSS NORTHEAST TEXAS AND SOUTHERN OKLAHOMA BY
EARLY THIS AFTERNOON AND CONTINUE THROUGH THE EVENING HOURS.

WINDS IN THE LOWER LEVELS OF THE ATMOSPHERE REMAIN FAVORABLE FOR THE
DEVELOPMENT OF ROTATING STORMS. THEREFORE THE THREAT WILL EXIST FOR
A FEW TORNADOES IN ADDITION TO LARGE HAIL AND DAMAGING STRAIGHT LINE
WIND.

THIS IS A POTENTIALLY DANGEROUS WEATHER SITUATION. RESIDENTS IN THE
FOUR STATE REGION ARE URGED TO REVIEW SEVERE WEATHER SAFETY RULES AND
TO LISTEN TO RADIO...TELEVISION AND NOAA WEATHER RADIO FOR POSSIBLE
WATCHES...WARNINGS AND STATEMENTS LATER TODAY.

ACTIVATION OF STORM SPOTTERS...EMERGENCY MANAGEMENT OFFICIALS AND
HAM RADIO OPERATORS WILL LIKELY BE REQUIRED THIS AFTERNOON AND
TONIGHT.

14

The office that day

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

Issued	Product	Office	Counties	Lasted
May 4, 2:35 AM CDT	Severe Thunderstorm Warning	SHV	Red River	45 min
May 4, 1:32 PM CDT	Tornado Warning	SHV	Franklin, Red River	48 min
May 4, 1:38 PM CDT	Tornado Warning	SHV	Smith	47 min
May 4, 2:05 PM CDT	Tornado Warning	SHV	Wood	40 min
May 4, 2:05 PM CDT	Tornado Warning	SHV	Titus	45 min
May 4, 2:33 PM CDT	Tornado Warning	SHV	Red River	47 min
May 4, 2:45 PM CDT	Tornado Warning	SHV	Bowie	45 min
May 4, 3:01 PM CDT	Tornado Warning	SHV	Gregg, Rusk	39 min
May 4, 3:29 PM CDT	Tornado Warning	SHV	Harrison	61 min
May 4, 4:03 PM CDT	Tornado Warning	SHV	Cass	47 min
May 4, 4:48 PM CDT	Severe Thunderstorm Warning	SHV	Wood	62 min
May 4, 5:06 PM CDT	Tornado Warning	SHV	Wood	49 min
May 4, 5:46 PM CDT	Severe Thunderstorm Warning	SHV	Smith	64 min
May 4, 6:26 PM CDT	Tornado Warning	SHV	Smith	64 min

Nearby

Tornado Warnings in Texas, 1999 Every tornado warning in 1999 Tornadoes 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.