Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 2, NWS Shreveport, LA

January 17, 2012Angelina County, Nacogdoches County, Texas

NWS Shreveport, LA issued this severe thunderstorm warning at Jan 17, 2012, 8:36 AM CST for Angelina County, Nacogdoches County, Texas. It was in force for 54 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: Jan 17, 2012, 8:36 AM CST (14:36 UTC)
Expired: Jan 17, 2012, 9:30 AM CST
In force: 54 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

Counties Angelina County, TX, Nacogdoches County, TX

The radar

The Shreveport radar (KSHV), 158 km from the middle of the area, began a volume at 14:38 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

Shreveport, LA (KSHV), launched 12:00Z, 2.6 hours before the alert went out and 165 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: 1305 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 635 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 254 m²/s²
0-3 km storm-relative helicity: 244 m²/s²
Significant tornado parameter: 1.7
Supercell composite: 7.9

Open this sounding in Storm Lab

The text

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

916 
WUUS54 KSHV 171436
SVRSHV
TXC005-347-171530-
/O.NEW.KSHV.SV.W.0002.120117T1436Z-120117T1530Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
836 AM CST TUE JAN 17 2012

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

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

* UNTIL 930 AM CST

* AT 836 AM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED 23 MILES WEST OF DIBOLL...OR 19 MILES SOUTHEAST
  OF CROCKETT...AND MOVING EAST AT 40 MPH.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 3113 9483 3116 9486 3123 9487 3126 9490
      3129 9489 3132 9491 3135 9496 3139 9496
      3143 9501 3151 9487 3161 9458 3124 9436
      3106 9433 3106 9459
TIME...MOT...LOC 1435Z 250DEG 36KT 3118 9519

$$

05

The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 16, 9:53 PM CST	Lake Wind Advisory	SHV	Bowie, Camp, Cass, Cherokee, Franklin, Gregg and 12 more	18 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.