Alert archive / Texas / Tornado Warnings in 2011
Tornado Warning 27, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this tornado warning at Dec 20, 2011, 12:12 AM CST for Polk County, San Jacinto County, Trinity 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
- Dec 20, 2011, 12:12 AM CST (06:12 UTC)
- Expired
- Dec 20, 2011, 12:45 AM CST
- In force
- 33 min
- Issued by
- NWS Houston/Galveston, TX
- Area
- Storm-based polygon
Counties Polk County, TX, San Jacinto County, TX, Trinity County, TX
The radar
The Houston radar (KHGX), 155 km from the middle of the area, began a volume at 06:12 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 nearest sounding before it
Lake Charles Mun, LA (KLCH), launched 00:00Z, 6.2 hours before the alert went out and 209 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1049 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 154 m²/s²
- 0-3 km storm-relative helicity
- 180 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
800
WFUS54 KHGX 200612
TORHGX
TXC373-407-455-200645-
/O.NEW.KHGX.TO.W.0027.111220T0612Z-111220T0645Z/
BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1212 AM CST TUE DEC 20 2011
THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A
* TORNADO WARNING FOR...
WESTERN POLK COUNTY IN SOUTHEAST TEXAS...
NORTHWESTERN SAN JACINTO COUNTY IN SOUTHEAST TEXAS...
SOUTHERN TRINITY COUNTY IN SOUTHEAST TEXAS...
* UNTIL 1245 AM CST
* AT 1207 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS
TORNADO WAS LOCATED NEAR POINT BLANK...MOVING NORTHEAST AT 30 MPH.
* LOCATIONS IN THE TORNADO WARNING INCLUDE BUT ARE NOT LIMITED TO
SEBASTOPOL...ONALASKA...AND GROVETON.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TORNADOES AT NIGHT ARE ESPECIALLY DANGEROUS. DO NOT WAIT UNTIL YOU
SEE OR HEAR A TORNADO - TAKE COVER NOW!
&&
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 3070 9524 3079 9534 3086 9533 3087 9534
3115 9504 3098 9486
TIME...MOT...LOC 0612Z 226DEG 27KT 3084 9522
$$2 follow-up statements
467 WWUS54 KHGX 200633 SVSHGX SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 1233 AM CST TUE DEC 20 2011 TXC407-200643- /O.CAN.KHGX.TO.W.0027.000000T0000Z-111220T0645Z/ SAN JACINTO TX- 1233 AM CST TUE DEC 20 2011 ...THE TORNADO WARNING FOR SAN JACINTO COUNTY IS CANCELLED... THE STORM THAT PROMPTED THE WARNING HAS WEAKED OR MOVED OUT OF THE AREA. && PLEASE REPORT SEVERE WEATHER TO THE COUNTY SHERIFF...LOCAL POLICE... OR DEPARTMENT OF PUBLIC SAFETY AND ASK THEM TO RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE. LAT...LON 3081 9510 3094 9526 3115 9504 3098 9486 TIME...MOT...LOC 0633Z 224DEG 30KT 3096 9508 $$ TXC373-455-200645- /O.CON.KHGX.TO.W.0027.000000T0000Z-111220T0645Z/ POLK TX-TRINITY TX- 1233 AM CST TUE DEC 20 2011 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1245 AM CST FOR TRINITY AND POLK COUNTIES... AT 1232 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A TORNADO. THIS TORNADO WAS LOCATED 7 MILES SOUTH OF GROVETON...OR 19 MILES NORTHWEST OF LIVINGSTON...MOVING NORTHEAST AT 35 MPH. THE TORNADO WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS OF THE INDICATED COUNTIES. PRECAUTIONARY/PREPAREDNESS ACTIONS... TORNADOES AT NIGHT ARE ESPECIALLY DANGEROUS. DO NOT WAIT UNTIL YOU SEE OR HEAR A TORNADO - TAKE COVER NOW! && 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 3081 9510 3094 9526 3115 9504 3098 9486 TIME...MOT...LOC 0633Z 224DEG 30KT 3096 9508 $$
914 WWUS54 KHGX 200643 SVSHGX SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 1243 AM CST TUE DEC 20 2011 TXC373-455-200653- /O.EXP.KHGX.TO.W.0027.000000T0000Z-111220T0645Z/ POLK TX-TRINITY TX- 1243 AM CST TUE DEC 20 2011 ...THE TORNADO WARNING FOR TRINITY AND POLK COUNTIES WILL EXPIRE AT 1245 AM CST... THE STORM THAT PROMPTED THE WARNING HAS WEAKED OR MOVED OUT OF THE AREA. PLEASE REPORT SEVERE WEATHER TO THE COUNTY SHERIFF...LOCAL POLICE... OR DEPARTMENT OF PUBLIC SAFETY AND ASK THEM TO RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE. LAT...LON 3081 9510 3094 9526 3115 9504 3098 9486 TIME...MOT...LOC 0643Z 224DEG 30KT 3102 9501 $$
The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 19, 9:57 PM CST | Small Craft Advisory | HGX | 6 hr | |
| Dec 20, 12:47 AM CST | Special Weather Statement | HGX | Trinity | 43 min |
| Dec 20, 2:11 AM CST | Special Weather Statement | HGX | Montgomery | 49 min |
| Dec 20, 3:43 AM CST | Special Weather Statement | HGX | Liberty | 32 min |
| Dec 20, 4:17 AM CST | Small Craft Advisory | HGX | 18 hr | |
| Dec 20, 7:15 AM CST | Special Marine Warning | HGX | 2 hr | |
| Dec 20, 10:22 AM CST | Special Marine Warning | HGX | 53 min |
Nearby
Tornado Warnings in Texas, 2011Every tornado warning in 2011Tornadoes in 2011
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.