Alert archive / Texas / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 2, NWS Houston/Galveston, TX

February 21, 2002Harris County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Feb 21, 2002, 5:23 PM CST for Harris County, Texas. It was in force for 37 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Feb 21, 2002, 5:23 PM CST (23:23 UTC)
Expired
Feb 21, 2002, 6:00 PM CST
In force
37 min
Issued by
NWS Houston/Galveston, TX
Area
Counties, with a storm outline in the text

County Harris County, TX

The radar

The Houston radar (KHGX), 59 km from the middle of the area, began a volume at 23:24 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

TimeReportWhereRemark
Feb 21, 5:23 PM CSTHail 1Jersey Village, TXStorm spotter reported 1.00 inch hail at FM 249 and Beltway 8.
Feb 21, 5:26 PM CSTHail 0.75Jersey Village, TXPolice department reported 3/4 inch hail at Jones Road and FM 1960.

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.

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 12:00Z, 11.4 hours before the alert went out and 210 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 12:00Z on 2002-02-21Temperature 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 12:00Z on 2002-02-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 square meters per square second.1939587897117Sfc1 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
2723 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
41 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 212323
SVRHOU
TXC201-220000-

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

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 600 PM CST

* AT 514 PM CST...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM NEAR 
  THE INTERSECTION OF HIGHWAY 290 AND BELTWAY 8...MOVING EAST AT 20  
  MPH.

* LOCATIONS IN THE PATH OF THE SEVERE THUNDERSTORM INCLUDE...
  JERSEY VILLAGE
  ALDINE
  BUSH-INTERCONTINENTAL AIRPORT
  HUMBLE
  LAKE HOUSTON DAM...SHELDON

HAIL UP TO THE SIZE OF DIMES IS LIKELY WITH THIS STORM. 

PUBLIC REPORTED DIME SIZED HAIL NEAR HIGHWAY 290 AND THE VICINITY OF 
BELTWAY 8 AT 517 PM.

MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR
BUSINESS. STAY AWAY FROM WINDOWS

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 3001 9559 2983 9558 2980 9504 3005 9504

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, 2 hours 43 minutes earlier.

Area forecast discussion, Feb 21, 2:40 PM CST, 2 hours 43 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, 4:34 PM CSTSevere Thunderstorm WarningHGXHarris, Waller41 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.