Alert archive / Texas / Tornado Watches in 1998

Tornado Watch 53

February 21, 19986 counties in Texas

The Storm Prediction Center issued this tornado watch at Feb 21, 1998, 4:00 PM CST for 6 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Feb 21, 1998, 4:00 PM CST (22:00 UTC)
Expired
Feb 21, 1998, 9:00 PM CST
In force
5 hr
Issued by
the Storm Prediction Center

Counties Brooks County, TX, Cameron County, TX, Hidalgo County, TX, Jim Hogg County, TX, Starr County, TX, Willacy County, TX

The radar

The Brownsville radar (KBRO), 129 km from the middle of the area, began a volume at 21:59 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.

Warnings issued inside it

6 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Feb 21, 4:20 PM CSTSevere Thunderstorm WarningBROStarr55 min
Feb 21, 4:35 PM CSTSevere Thunderstorm WarningBROJim Hogg60 min
Feb 21, 4:42 PM CSTSevere Thunderstorm WarningBROBrooks63 min
Feb 21, 5:18 PM CSTSevere Thunderstorm WarningBROHidalgo, Starr87 min
Feb 21, 5:51 PM CSTSevere Thunderstorm WarningBROBrooks, Kenedy59 min
Feb 21, 7:55 PM CSTSevere Thunderstorm WarningBROCameron60 min

The nearest sounding before it

Brownsville Intl, TX (KBRO), launched 12:00Z, 10.0 hours before the alert went out and 131 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, Brownsville Intl, TX at 12:00Z on 1998-02-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLEL10008507005003002001001 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, Brownsville Intl, TX at 12:00Z on 1998-02-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 200 square meters per square second.1939587897117136Sfc1 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
2 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
708 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
200 m²/s²
0-3 km storm-relative helicity
398 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.

911 
WWUS9 KMKC 212130
SEL3  
MKC WW 212130
TXZ000-220300-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 53
STORM PREDICTION CENTER NORMAN OK
330 PM CST SAT FEB 21 1998

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   SOUTHERN TEXAS                              
   AND ADJACENT COASTAL WATERS

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 400 PM UNTIL 900
PM CST.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 35 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 70 MILES NORTHWEST OF MCALLEN TEXAS TO 25
MILES NORTH NORTHEAST OF BROWNSVILLE TEXAS.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...  CONTINUE...WW 52...

DISCUSSION...THUNDERSTORMS INCREASING AHEAD OF SURFACE FRONT AND
UPPER LEVEL TROUGH IN VERY UNSTABLE AIR MASS WHERE CAPES ABOVE 
3000 J/KG. VEERING WIND PROFILE AND INCREASING FLOW ALOFT WILL 
RESULT IN FAVORABLE SHEAR FOR TORNADIC SUPERCELLS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. 
MEAN STORM MOTION VECTOR 26035.


...ROGASH

272,0990 264,0971 254,0971 262,0990

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 21, 3:00 PM CSTTornado WatchSPCAransas, Atascosa, Bandera, Bee, Bexar, Brooks and 27 more6 hr

Nearby

Tornado Watches in Texas, 1998Every tornado watch 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.