Alert archive / Texas / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 83, NWS Austin/San Antonio, TX

May 10, 1999Travis County, Williamson County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 10, 1999, 5:05 PM CDT for Travis County, Williamson County, Texas. It was in force for 45 min. 2 reports 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: May 10, 1999, 5:05 PM CDT (22:05 UTC)
Expired: May 10, 1999, 5:50 PM CDT
In force: 45 min
Issued by: NWS Austin/San Antonio, TX
Area: Whole counties

Counties Travis County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 39 km from the middle of the area, began a volume at 22:05 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
May 10, 5:20 PM CDT	Hail 1	Jonestown, TX
May 10, 5:20 PM CDT	Hail 1	Cedar Park, TX

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 nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 10.1 hours before the alert went out and 263 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: 8 J/kg
Mixed-layer CIN: -449 J/kg
Mixed-layer LCL: 927 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 276 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.

999 
WUUS1 KSAT 102206 RRA
SVRSAT
TXC453-491-102250-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
505 PM CDT MON MAY 10 1999

THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WILLIAMSON COUNTY IN TEXAS
  NORTHERN TRAVIS COUNTY IN TEXAS

* UNTIL 550 PM CDT

* AT AT 500 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR
  INDICATED A SEVERE THUNDERSTORM THE TRAVIS COUNTY LINE NEAR
  SPICEWOOD... MOVING TO THE EAST NORTHEAST AT 25 MPH..

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  NORTHERN PORTIONS OF AUSTIN BY 515 PM
  AND ROUND ROCK BY 525 PM.

DAMAGING WINDS AND LARGE HAIL ARE LIKELY. GO INSIDE A STURDY
BUILDING AND STAY AWAY FROM WINDOWS

JPB

The office that day

Everything else NWS Austin/San Antonio, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 9, 11:07 PM CDT	Severe Thunderstorm Warning	EWX	Edwards, Val Verde	58 min
May 9, 11:58 PM CDT	Severe Thunderstorm Warning	EWX	Edwards	62 min
May 10, 12:18 AM CDT	Tornado Warning	EWX	Edwards	62 min
May 10, 12:25 AM CDT	Flash Flood Warning	EWX	Edwards	3 hr
May 10, 12:56 AM CDT	Severe Thunderstorm Warning	EWX	Burnet, Llano	59 min
May 10, 1:08 AM CDT	Severe Thunderstorm Warning	EWX	Edwards	62 min
May 10, 10:02 AM CDT	Severe Thunderstorm Warning	EWX	Williamson	58 min
May 10, 11:01 AM CDT	Severe Thunderstorm Warning	EWX	Williamson	59 min
May 10, 1:37 PM CDT	Flash Flood Warning	EWX	Burnet, Llano	3 hr
May 10, 2:08 PM CDT	Flash Flood Warning	EWX	Williamson	2 hr
May 10, 2:40 PM CDT	Severe Thunderstorm Warning	EWX	Travis, Williamson	65 min
May 10, 3:49 PM CDT	Severe Thunderstorm Warning	EWX	Lee	56 min
May 10, 4:50 PM CDT	Flash Flood Warning	EWX	Williamson	3 hr
May 10, 6:57 PM CDT	Severe Thunderstorm Warning	EWX	Caldwell, Gonzales, Guadalupe	48 min

Nearby

Severe Thunderstorm Warnings in Texas, 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.