Alert archive / Arkansas / Tornado Warnings in 1999

Tornado Warning 77, NWS Shreveport, LA

May 5, 1999Union County, Arkansas

NWS Shreveport, LA issued this tornado warning at May 5, 1999, 7:07 AM CDT for Union County, Arkansas. It was in force for 63 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 5, 1999, 7:07 AM CDT (12:07 UTC)
Expired: May 5, 1999, 8:10 AM CDT
In force: 63 min
Issued by: NWS Shreveport, LA
Area: Whole counties

County Union County, AR

The radar

The Shreveport radar (KSHV), 141 km from the middle of the area, began a volume at 12:09 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, 0.1 hours before the alert went out and 132 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: 2215 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 624 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 208 m²/s²
0-3 km storm-relative helicity: 255 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 9.7

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLIT 051225
TORSHV

ARC139-051325-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
ISSUED BY NATIONAL WEATHER SERVICE LITTLE ROCK AR
707 AM CDT WED MAY 5 1999

THE NATIONAL WEATHER SERVICE IN LITTLE ROCK HAS ISSUED A

* TORNADO WARNING FOR...
  UNION COUNTY COUNTY IN SOUTHWESTERN ARKANSAS

* UNTIL 810 AM CDT

* AT 705 AM CDT... DOPPLER WEATHER RADAR INDICATED A TORNADO 1035 MILES
  SOUTHWEST OF STRONG...MOVING NORTHEAST AT 305 MPH.

THE TORNADO IS EXPECTED TO REMAIN MOSTLY IN RURAL AREAS.

A DOPPLER RADAR DETECTED TORNADO MEANS THAT THERE IS STRONG ROTATION
WITHIN A STORM. THE STORM MAY NOT BE PRODUCING A TORNADO AT THE MOMENT.
..BUT IS EXPECTED TO DURING THE WARNING PERIOD. FOR YOUR SAFETY...GO
INDOORS NOW TO AN INTERIOR ROOM AWAY FROM WINDOWS.

29

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 5, 2:50 AM CDT, 4 hours 17 minutes earlier.

Area forecast discussion, May 5, 2:50 AM CDT, 4 hours 17 minutes before

FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
250 AM CDT WED MAY 5 1999

STUBBORN AREA OF SHOWERS AND THUNDERSTORMS STILL OCCURRING JUST
NORTHWEST AND NORTH OF SHV. IR SATELLITE SHOWS UPPER LOW SPINNING
OVER THE NORTHERN PLAINS WITH LARGE AREA OF SHOWERS AND
THUNDERSTORMS OVER TENNESSESS...EASTERN ARKANSAS AND NORTHEAST
LOUISIANA. SURFACE LOW CENTERED OVER NEBRASKA WITH DRY LINE OVER
CENTRAL OKLAHOMA INTO NORTH CENTRAL TEXAS. MODELS SHOW 5H LOW
CONTINUEING TO SPIN ACROSS THE NORTHERN PLAINS AND GRADUALLY WORK TO
THE EAST INTO THE WESTERN GREAT LAKES BY THURSDAY NIGHT AS UPPER
RIDGE DEVELOPS OVER THE ROCKIES. SURFACE COLD FRONT WILL MOVE
THROUGH CWA TODAY AND WITH LOW LEVEL MOISTURE IN PLACE AND UPPER
LEVEL DIVERGENCE AND JET MAX COMING ACROSS TEXAS SCATTERED SHOWERS
AND THUNDERSTORMS MAY DEVELOP JUST AHEAD OF THE FRONT IN LOUISIANA
AND ARKANSAS. WITH CAPE VALUES PROGGED TO BE OVER 2000 AND LITTLE
CAP SOME STORMS MAY BE SEVERE IN SOUTH CENTRAL ARKANSAS AND NORTH
CENTRAL LOUISIANA THIS AFTERNOON AND EARLY THIS EVENING. AS MUCH DRIER
AIR MOVES IN TONIGHT SKIES WILL CLEAR AND TEMPERATURES WILL BE
COOLER. HIGHS SHOULD BE ABOUT 5 DEGREES COOLER THURSDAY.

POPS GUIDANCE SEEM TOO LOW SO WENT HIGHER AND LOWERED MAX TEMPS
SLIGHTLY TODAY AND RAISED TEMPS FOR OTHER PERIODS. BELIEVE MLU MAY
AREA MAY SEE CHANCE OF THUNDERSTORMS WELL INTO THIS EVENING. CLOUDY
SKIES THIS MORNING SHOULD BECOME PARTLY CLOUDY TODAY EXCEPT OVER
NORTH CENTRAL LOUISIANA.

SHV  85/58/79/53 3311   MLU  86/60/80/53 4511   TXK  83/52/77/50 3110
TYR  83/55/78/51 2110   LFK  87/57/80/52 3210

09

In the hours before

Local storm report, May 5, 5:02 AM CDT, 2 hours 5 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SHREVEPORT LA
502 AM CDT WED MAY 05 1999

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

0430 AM    LAKE CLAIBORNE            LA   1 INCH HAIL
05/05/99   CLAIBORNE                      FROM S.O.

IV

The office that day

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

Issued	Product	Office	Counties	Lasted
May 4, 7:15 PM CDT	Tornado Warning	SHV	Union	30 min
May 5, 6:29 AM CDT	Severe Thunderstorm Warning	SHV	Union	56 min
May 5, 1:06 PM CDT	Severe Thunderstorm Warning	SHV	Union	19 min
May 5, 2:35 PM CDT	Severe Thunderstorm Warning	SHV	Columbia	35 min
May 5, 2:47 PM CDT	Severe Thunderstorm Warning	SHV	Union	33 min
May 5, 2:57 PM CDT	Severe Thunderstorm Warning	SHV	Columbia	48 min
May 5, 4:42 PM CDT	Severe Thunderstorm Warning	SHV	Union	48 min

Nearby

Tornado Warnings in Arkansas, 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.