Alert archive / Texas / Tornado Warnings in 2021

Tornado Warning 10, NWS Houston/Galveston, TX

May 11, 2021Houston County, Trinity County, Walker County, Texas

NWS Houston/Galveston, TX issued this tornado warning at May 11, 2021, 4:27 PM CDT for Houston County, Trinity County, Walker County, Texas. It was in force for 33 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
May 11, 2021, 4:27 PM CDT (21:27 UTC)
Expired
May 11, 2021, 5:00 PM CDT
In force
33 min
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

Counties Houston County, TX, Trinity County, TX, Walker County, TX

The radar

The Houston radar (KHGX), 176 km from the middle of the area, began a volume at 21:31 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.

The watch it was issued in

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

IssuedProductOfficeLasted
May 11, 3:04 PM CDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 9.5 hours before the alert went out and 218 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, Shreveport, LA at 12:00Z on 2021-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Shreveport, LA at 12:00Z on 2021-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 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
605 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
438 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.4

Open this sounding in Storm Lab

The text

As transmitted.

602 
WFUS54 KHGX 112127
TORHGX
TXC225-455-471-112200-
/O.NEW.KHGX.TO.W.0010.210511T2127Z-210511T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Houston/Galveston TX
427 PM CDT Tue May 11 2021

The National Weather Service in League City has issued a

* Tornado Warning for...
  Southwestern Trinity County in southeastern Texas...
  South central Houston County in southeastern Texas...
  Northern Walker County in southeastern Texas...

* Until 500 PM CDT.
    
* At 427 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Lovelady, or 16 miles southeast of Austonio,
  moving east at 20 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Groveton around 500 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3101 9547 3114 9546 3113 9507 3091 9513
TIME...MOT...LOC 2127Z 277DEG 17KT 3107 9540 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$
2 follow-up statements
134 
WWUS54 KHGX 112138
SVSHGX

Severe Weather Statement
National Weather Service Houston/Galveston TX
438 PM CDT Tue May 11 2021

TXC471-112146-
/O.CAN.KHGX.TO.W.0010.000000T0000Z-210511T2200Z/
Walker TX-
438 PM CDT Tue May 11 2021

...THE TORNADO WARNING FOR NORTHERN WALKER COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
southeastern Texas.

LAT...LON 3100 9542 3112 9541 3113 9507 3091 9513
TIME...MOT...LOC 2136Z 284DEG 20KT 3104 9533 

$$

TXC225-455-112200-
/O.CON.KHGX.TO.W.0010.000000T0000Z-210511T2200Z/
Trinity TX-Houston TX-
438 PM CDT Tue May 11 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR
SOUTHWESTERN TRINITY AND SOUTH CENTRAL HOUSTON COUNTIES...
    
At 436 PM CDT, a severe thunderstorm capable of producing a tornado 
was located 5 miles north of Trinity, or 20 miles south of Crockett, 
moving east at 25 mph.

HAZARD...Tornado and half dollar size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Groveton around 505 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3100 9542 3112 9541 3113 9507 3091 9513
TIME...MOT...LOC 2136Z 284DEG 20KT 3104 9533 

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$
505 
WWUS54 KHGX 112150
SVSHGX

Severe Weather Statement
National Weather Service Houston/Galveston TX
450 PM CDT Tue May 11 2021

TXC225-112159-
/O.CAN.KHGX.TO.W.0010.000000T0000Z-210511T2200Z/
Houston TX-
450 PM CDT Tue May 11 2021

...THE TORNADO WARNING FOR SOUTH CENTRAL HOUSTON COUNTY IS
CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
southeastern Texas.

LAT...LON 3098 9533 3111 9530 3113 9507 3091 9513
TIME...MOT...LOC 2149Z 277DEG 17KT 3103 9526 

$$

TXC455-112200-
/O.CON.KHGX.TO.W.0010.000000T0000Z-210511T2200Z/
Trinity TX-
450 PM CDT Tue May 11 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR
SOUTHWESTERN TRINITY COUNTY...
    
At 449 PM CDT, a severe thunderstorm capable of producing a tornado
was located 7 miles west of Groveton, or 21 miles southwest of Apple
Springs, moving east at 20 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Groveton around 510 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3098 9533 3111 9530 3113 9507 3091 9513
TIME...MOT...LOC 2149Z 277DEG 17KT 3103 9526 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 11, 3:27 AM CDTFlash Flood WatchHGXBrazos, Grimes, Houston, Madison, Montgomery, Polk and 3 more24 hr
May 11, 6:28 AM CDTAreal Flood AdvisoryHGXPolk3 hr
May 11, 6:46 AM CDTSpecial Weather StatementHGXPolk44 min
May 11, 7:25 AM CDTSevere Thunderstorm WarningHGXPolk35 min
May 11, 8:34 AM CDTAreal Flood AdvisoryHGXPolk3 hr
May 11, 10:03 AM CDTSmall Craft AdvisoryHGX3 hr
May 11, 11:05 AM CDTSpecial Weather StatementHGXHouston10 min
May 11, 1:09 PM CDTSpecial Weather StatementHGXMadison36 min
May 11, 1:21 PM CDTSpecial Weather StatementHGXBrazos39 min
May 11, 1:28 PM CDTTornado WarningHGXHouston, Madison, Walker32 min
May 11, 1:57 PM CDTTornado WarningHGXHouston, Madison, Walker18 min
May 11, 2:20 PM CDTTornado Warning Tornado observedHGXHouston, Trinity, Walker25 min
May 11, 2:41 PM CDTSevere Thunderstorm WarningHGXHouston64 min
May 11, 3:09 PM CDTSevere Thunderstorm WarningHGXBrazos, Burleson52 min
May 11, 3:31 PM CDTSevere Thunderstorm WarningHGXHouston44 min
May 11, 3:53 PM CDTSevere Thunderstorm WarningHGXHouston37 min
May 11, 4:10 PM CDTSevere Thunderstorm WarningHGXBrazos, Burleson, Grimes35 min
May 11, 4:14 PM CDTTornado WarningHGXHouston, Trinity31 min
May 11, 4:44 PM CDTTornado WarningHGXHouston, Polk, Trinity46 min
May 11, 4:54 PM CDTSevere Thunderstorm WarningHGXPolk, San Jacinto, Trinity51 min
May 11, 5:22 PM CDTSpecial Weather StatementHGXMontgomery, Waller38 min
May 11, 5:34 PM CDTAreal Flood AdvisoryHGXHouston, Madison116 min
May 11, 5:41 PM CDTSevere Thunderstorm WarningHGXLiberty, Polk, San Jacinto, Trinity64 min
May 11, 5:49 PM CDTAreal Flood AdvisoryHGXHouston, San Jacinto, Trinity, Walker116 min
May 11, 6:18 PM CDTSevere Thunderstorm WarningHGXLiberty42 min

Nearby

Tornado Warnings in Texas, 2021Every tornado warning in 2021Tornadoes in 2021

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.