Alert archive / Texas / Tornado Warnings in 2012

Tornado Warning 24, NWS Houston/Galveston, TX

March 20, 2012Harris County, Texas

NWS Houston/Galveston, TX issued this tornado warning at Mar 20, 2012, 7:45 AM CDT for Harris County, Texas. It was in force for 30 min. 3 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
Mar 20, 2012, 7:45 AM CDT (12:45 UTC)
Expired
Mar 20, 2012, 8:15 AM CDT
In force
30 min
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon

County Harris County, TX

The radar

The Houston radar (KHGX), 54 km from the middle of the area, began a volume at 12:45 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
Mar 20, 7:50 AM CDTFUNNEL CLOUD2 Sw Bunker Hill Villag, TXFUNNEL CLOUD SIGHTED FROM MARATHON TOWER. APPEARED TO BE IN CONTACT WITH THE GROUND SO POSSIBLE TORNADO. NO DAMAGE CONFIRMED.
Mar 20, 8:00 AM CDTTSTM WND DMG2 Sw Bunker Hill Villag, TXTREES DOWN AND FENCES BLOWN DOWN. TIME ESIMATED BASED ON RADAR.
Mar 20, 8:00 AM CDTTSTM WND DMGPiney Point Village, TXMANY TREES DOWN AND DAMAGE TO HOMES. POSSIBLE TORNADO.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Mar 20, 12:48 AM CDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 0.8 hours before the alert went out and 230 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 2012-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1368 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2012-03-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 225 square meters per square second.193958Sfc1 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
1368 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
555 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
225 m²/s²
0-3 km storm-relative helicity
338 m²/s²
Significant tornado parameter
1.2
Supercell composite
8.8

Open this sounding in Storm Lab

The text

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

292 
WFUS54 KHGX 201245
TORHGX
TXC201-201315-
/O.NEW.KHGX.TO.W.0024.120320T1245Z-120320T1315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
745 AM CDT TUE MAR 20 2012

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL HARRIS COUNTY IN SOUTHEAST TEXAS...

* UNTIL 815 AM CDT

* AT 741 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS TORNADO
  WAS LOCATED NEAR BUNKER HILL VILLAGE... MOVING NORTHEAST AT 30 MPH.

* LOCATIONS IN THE TORNADO WARNING INCLUDE BUT ARE NOT LIMITED TO THE
  GALLERIA AND PINEY POINT VILLAGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS IN THE INTERIOR HALLWAY OR
A ROOM SUCH AS A CLOSET ON THE LOWEST LEVEL OF A STURDY BUILDING. USE
BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM
WINDOWS.

IF YOU ARE INSIDE A MOBILE HOME OR VEHICLE...EVACUATE THEM
IMMEDIATELY AND SEEK SHELTER INSIDE A STURDY BUILDING. AS A LAST
RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW SPOT AND COVER YOUR
HEAD WITH YOUR HANDS.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 9 AM CDT FOR THE 
WARNED AREA.

&&

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

LAT...LON 2977 9557 2976 9543 2968 9553 2971 9565
TIME...MOT...LOC 1245Z 247DEG 28KT 2974 9557

$$
2 follow-up statements
961 
WWUS54 KHGX 201257
SVSHGX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
757 AM CDT TUE MAR 20 2012

TXC201-201315-
/O.CON.KHGX.TO.W.0024.000000T0000Z-120320T1315Z/
HARRIS TX-
757 AM CDT TUE MAR 20 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 815 AM CDT FOR HARRIS
COUNTY...

AT 755 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO.  THIS TORNADO WAS LOCATED NEAR PINEY POINT 
VILLAGE...OR NEAR HUNTERS CREEK VILLAGE...MOVING EAST AT 25 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS IN THE INTERIOR HALLWAY OR
A ROOM SUCH AS A CLOSET ON THE LOWEST LEVEL OF A STURDY BUILDING. USE
BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM
WINDOWS.

IF YOU ARE INSIDE A MOBILE HOME OR VEHICLE...EVACUATE THEM
IMMEDIATELY AND SEEK SHELTER INSIDE A STURDY BUILDING. AS A LAST
RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW SPOT AND COVER YOUR
HEAD WITH YOUR HANDS.

&&

A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 9 AM CDT.

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

LAT...LON 2977 9557 2976 9543 2968 9553 2971 9565
TIME...MOT...LOC 1257Z 247DEG 28KT 2978 9547

$$
893 
WWUS54 KHGX 201311
SVSHGX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
811 AM CDT TUE MAR 20 2012

TXC201-201321-
/O.EXP.KHGX.TO.W.0024.000000T0000Z-120320T1315Z/
HARRIS TX-
811 AM CDT TUE MAR 20 2012

...THE TORNADO WARNING FOR HARRIS COUNTY WILL EXPIRE AT 815 AM CDT...

THE STORM THAT PROMPTED THE WARNING HAS WEAKENED OR MOVED OUT OF THE
AREA.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 9 AM CDT.

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

LAT...LON 2977 9557 2976 9543 2968 9553 2971 9565
TIME...MOT...LOC 1311Z 247DEG 28KT 2982 9535

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 20, 2:24 AM CDTSpecial Weather StatementHGXBrazos, Burleson, Washington51 min
Mar 20, 3:29 AM CDTSpecial Weather StatementHGXBrazos, Burleson, Madison, Washington61 min
Mar 20, 3:48 AM CDTSpecial Weather StatementHGXBrazos, Burleson, Madison, Washington42 min
Mar 20, 3:59 AM CDTAreal Flood AdvisoryHGXBrazos, Burleson2 hr
Mar 20, 4:59 AM CDTAreal Flood AdvisoryHGXAustin, Brazos, Burleson, Colorado, Grimes, Madison and 1 more2 hr
Mar 20, 5:25 AM CDTSpecial Weather StatementHGXAustin, Colorado65 min
Mar 20, 5:38 AM CDTSevere Thunderstorm WarningHGXAustin, Colorado, Waller, Washington, Wharton52 min
Mar 20, 5:53 AM CDTSpecial Marine WarningHGX112 min
Mar 20, 6:39 AM CDTSpecial Weather StatementHGXMontgomery, Waller66 min
Mar 20, 7:32 AM CDTSpecial Weather StatementHGXFort Bend58 min
Mar 20, 7:44 AM CDTSpecial Marine WarningHGX2 hr
Mar 20, 7:49 AM CDTAreal Flood AdvisoryHGXHarris, Montgomery3 hr
Mar 20, 7:59 AM CDTAreal Flood AdvisoryHGXAustin, Burleson, Washington61 min
Mar 20, 8:08 AM CDTCoastal Flood StatementHGXBrazoria, Chambers, Galveston, Harris, Matagorda7 hr
Mar 20, 8:17 AM CDTTornado WarningHGXBrazoria23 min
Mar 20, 8:34 AM CDTSpecial Weather StatementHGXHarris56 min
Mar 20, 8:41 AM CDTSpecial Marine WarningHGX94 min
Mar 20, 9:02 AM CDTRiver Flood WarningHGXBrazos, Grimes, Madison5 days
Mar 20, 9:02 AM CDTRiver Flood WarningHGXBurleson, Lee48 hr
Mar 20, 9:02 AM CDTRiver Flood WarningHGXBurleson, Lee4 days
Mar 20, 9:18 AM CDTSpecial Weather StatementHGXLiberty57 min
Mar 20, 9:21 AM CDTRiver Flood WarningHGXMontgomery60 hr
Mar 20, 9:21 AM CDTRiver Flood WarningHGXHarris, Liberty6 days
Mar 20, 9:29 AM CDTRiver Flood WarningHGXAustin, Fort Bend, Wharton4 days
Mar 20, 9:29 AM CDTRiver Flood WarningHGXBrazoria, Fort Bend, Wharton22 hr
Mar 20, 9:32 AM CDTSpecial Weather StatementHGXChambers, Galveston43 min
Mar 20, 10:02 AM CDTSpecial Marine WarningHGX88 min
Mar 20, 10:13 AM CDTAreal Flood AdvisoryHGXBrazoria, Chambers, Galveston62 min
Mar 20, 11:27 AM CDTSpecial Marine WarningHGX93 min

Nearby

Tornado Warnings in Texas, 2012Every tornado warning in 2012Tornadoes in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.