Alert archive / Texas / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 3, NWS Houston/Galveston, TX

February 21, 2002Brazoria County, Galveston County, Harris County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Feb 21, 2002, 6:18 PM CST for Brazoria County, Galveston County, Harris County, Texas. It was in force for 27 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Feb 21, 2002, 6:18 PM CST (00:18 UTC)
Expired
Feb 21, 2002, 6:45 PM CST
In force
27 min
Issued by
NWS Houston/Galveston, TX
Area
Counties, with a storm outline in the text

Counties Brazoria County, TX, Galveston County, TX, Harris County, TX

The radar

The Houston radar (KHGX), 24 km from the middle of the area, began a volume at 00:19 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 0.3 hours before the alert went out and 212 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, Lake Charles Mun, LA at 00:00Z on 2002-02-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Lake Charles Mun, LA at 00:00Z on 2002-02-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -11 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2422 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
-11 m²/s²
0-3 km storm-relative helicity
14 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.

000 
WUUS54 KHGX 220018
SVRHOU
TXC039-167-201-220045-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
617 PM CST THU FEB 21 2002

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  HARRIS COUNTY IN SOUTHEAST TEXAS
  BRAZORIA COUNTY IN SOUTHEAST TEXAS
  GALVESTON COUNTY IN SOUTHEAST TEXAS

* UNTIL 645 PM CST

* AT 614 PM CST...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 7
  MILES WEST OF BROOKSIDE VILLAGE...MOVING EAST AT 30 MPH.

* LOCATIONS IN THE PATH OF THE SEVERE THUNDERSTORM INCLUDE...
  BROOKSIDE VILLAGE
  PEARLAND
  FRIENDSWOOD...ELLINGTON FIELD
  WEBSTER

THIS STORM MAY PRODUCE LARGE DAMAGING HAIL...RESULTING IN EXTENSIVE
PROPERTY DAMAGE OR SERIOUS INJURY. AVOID WINDOWS AND TAKE COVER NOW

PLEASE REPORT SEVERE WEATHER TO THE COUNTY SHERIFF...LOCAL POLICE...
OR DEPARTMENT OF PUBLIC SAFETY. THEY WILL RELAY YOUR REPORT TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 2962 9542 2954 9543 2940 9514 2963 9509

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 Houston/Galveston, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Feb 21, 2:40 PM CST, 3 hours 38 minutes earlier.

Area forecast discussion, Feb 21, 2:40 PM CST, 3 hours 38 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
240 PM CST THU FEB 21 2002

WE ARE BACK IN BUSINESS AFTER AN AWIPS SOFTWARE UPGRADE. THANKS TO
SURROUNDING OFFICES FOR KEEPING AN EYE ON THINGS.

WILL BE DOING SOME SIG REVISIONS TO THE TNGT PERIOD OF THE FCST. ALL
MODELS CONT TO SHOW INCRG MOISTURE ASSOCIATED WITH FROPA TNGT. UPR
TROF IS ALSO FAIRLY HEALTHY...AND RADAR TRENDS SHOW SLOW INCR IN
ACTIVITY JUST N OF CWA. WITH THE ABV IN MIND...WILL USE HI CHC AND
LKLY POPS TNGT.

DRYING TAKES PLACE FROM N TO S TMRW MORNING. WILL MAINTAIN SLGT CHC
POPS COAST EARLY.

NEXT CDFNT THROUGH ON MON. LOOKS LIKE IT MIGHT HAVE SLIGHTLY MORE
MOISTURE TO WORK WITH THAN PREV RUNS. WILL INCLUDE A SLGT CHC FOR
MON.

WILL HOIST AN SCA THIS UPDATE. TIGHT GRADIENT AND CAA BEHIND FNT SHD
LEAD TO 20 KT OR HIGHER SPEEDS OVR THE MARINE AREA TNGT.

46/45/39/BT

.HGX...SMALL CRAFT ADVISORY ALL WATERS.

PRELIMS...
CLL UU 045/062 033/071 048 500
IAH BU 045/062 034/071 049 610
GLS BU 048/062 046/064 055 720 (510 SW)

The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 21, 6:20 PM CSTSpecial Marine WarningHGX115 min
Feb 21, 7:19 PM CSTSpecial Marine WarningHGX116 min

Nearby

Severe Thunderstorm Warnings in Texas, 2002Every severe thunderstorm warning in 2002

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.