Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 331, NWS Shreveport, LA

December 25, 2012Angelina County, Nacogdoches County, Texas

NWS Shreveport, LA issued this severe thunderstorm warning at Dec 25, 2012, 10:12 AM CST for Angelina County, Nacogdoches County, Texas. It was in force for 33 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: Dec 25, 2012, 10:12 AM CST (16:12 UTC)
Expired: Dec 25, 2012, 10:45 AM CST
In force: 33 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

Counties Angelina County, TX, Nacogdoches County, TX

The radar

The Shreveport radar (KSHV), 133 km from the middle of the area, began a volume at 16:14 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

Time	Report	Where	Remark
Dec 25, 10:12 AM CST	TSTM WND DMG	Lufkin, TX	TREES DOWN ON OAKWOOD ROAD IN LUFKIN
Dec 25, 10:30 AM CST	TSTM WND DMG	Chireno, TX	TREE DOWN ON FM 95

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.

Issued	Product	Office	Lasted
Dec 25, 9:02 AM CST	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 4.2 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1505 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 500 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 265 m²/s²
0-3 km storm-relative helicity: 353 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 10.9

Open this sounding in Storm Lab

The text

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

750 
WUUS54 KSHV 251612
SVRSHV
TXC005-347-251645-
/O.NEW.KSHV.SV.W.0331.121225T1612Z-121225T1645Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
1012 AM CST TUE DEC 25 2012

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWESTERN ANGELINA COUNTY IN EASTERN TEXAS...
  THIS INCLUDES THE CITY OF LUFKIN...
  CENTRAL NACOGDOCHES COUNTY IN EASTERN TEXAS...
  THIS INCLUDES THE CITY OF NACOGDOCHES...

* UNTIL 1045 AM CST

* AT 1010 AM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR LUFKIN...AND MOVING NORTHEAST AT 55 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  POLLOK...HUNTINGTON...WODEN...MELROSE AND MARTINSVILLE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

NATIONAL WEATHER SERVICE METEOROLOGISTS HAVE DETECTED SOME WEAK
ROTATION WITHIN THIS STORM. WHILE NOT IMMEDIATELY LIKELY...A TORNADO
MAY STILL DEVELOP. IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO
A PLACE OF SAFETY IN A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

&&

LAT...LON 3144 9499 3152 9487 3154 9489 3179 9459
      3158 9431 3153 9431 3117 9469
TIME...MOT...LOC 1612Z 217DEG 47KT 3131 9470

$$

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 25, 1:39 AM CST	Lake Wind Advisory	SHV	Angelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more	28 hr
Dec 25, 2:30 AM CST	Winter Storm Warning	SHV	Bowie, Red River	19 hr
Dec 25, 3:21 AM CST	Severe Thunderstorm Warning	SHV	Cherokee, Nacogdoches, Panola, Rusk, Smith	42 min
Dec 25, 5:04 AM CST	Severe Thunderstorm Warning	SHV	Bowie, Cass, Morris	41 min
Dec 25, 9:42 AM CST	Tornado Warning	SHV	Angelina, Cherokee	18 min
Dec 25, 10:37 AM CST	Severe Thunderstorm Warning	SHV	Angelina, Nacogdoches, San Augustine, Shelby	38 min
Dec 25, 11:00 AM CST	Severe Thunderstorm Warning	SHV	Sabine	45 min

Nearby

Severe Thunderstorm Warnings in Texas, 2012 Every severe thunderstorm warning 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.