Alert archive / Louisiana / Tornado Warnings in 2017

Tornado Warning 18, NWS Shreveport, LA

January 21, 2017Claiborne Parish, Union Parish, Louisiana; Columbia County, Union County, Arkansas

NWS Shreveport, LA issued this tornado warning at Jan 21, 2017, 7:21 PM CST for Claiborne Parish, Union Parish, Louisiana; Columbia County, Union County, Arkansas. It was in force for 54 min. 1 report 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: Jan 21, 2017, 7:21 PM CST (01:21 UTC)
Expired: Jan 21, 2017, 8:15 PM CST
In force: 54 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

Counties Columbia County, AR, Union County, AR, Claiborne Parish, LA, Union Parish, LA

The radar

The Shreveport radar (KSHV), 110 km from the middle of the area, began a volume at 01:23 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
Jan 21, 7:30 PM CST	HAIL 1	Spearsville, LA	1 INCH HAIL IN SPEARSVILLE.

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
Jan 21, 3:41 PM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Shreveport, LA (KBAD), launched 00:00Z, 1.4 hours before the alert went out and 101 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: 1144 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 813 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 200 m²/s²
0-3 km storm-relative helicity: 285 m²/s²
Significant tornado parameter: 1.3
Supercell composite: 9.0

Open this sounding in Storm Lab

The text

As transmitted.

918 
WFUS54 KSHV 220121
TORSHV
ARC027-139-LAC027-111-220215-
/O.NEW.KSHV.TO.W.0018.170122T0121Z-170122T0215Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Shreveport LA
721 PM CST SAT JAN 21 2017

The National Weather Service in Shreveport has issued a

* Tornado Warning for...
  Southwestern Union County in south central Arkansas...
  Southeastern Columbia County in southwestern Arkansas...
  Northwestern Union Parish in north central Louisiana...
  Northern Claiborne Parish in northwestern Louisiana...

* Until 815 PM CST
    
* At 721 PM CST, a severe thunderstorm capable of producing a tornado
  was located 8 miles east of Haynesville, or 12 miles north of
  Homer, moving northeast at 30 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. 

* Locations impacted include...
  Junction City, Haynesville, Spearsville, Lillie, Hew Hope, Three
  Creeks, Corney Lake, Antioch, Taylorville and Summerfield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 3283 9307 3303 9320 3313 9285 3303 9262
      3301 9255 3289 9252
TIME...MOT...LOC 0121Z 246DEG 25KT 3296 9300 

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

$$

06

The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 21, 6:04 PM CST	Tornado Warning	SHV	Claiborne	41 min
Jan 21, 6:04 PM CST	Tornado Warning	SHV	Bossier, Caddo	56 min
Jan 21, 6:13 PM CST	Tornado Warning	SHV	Grant, Winn	47 min
Jan 21, 6:14 PM CST	Tornado Warning	SHV	Grant, Natchitoches	61 min
Jan 21, 6:16 PM CST	Severe Thunderstorm Warning	SHV	Claiborne, Webster	59 min
Jan 21, 6:22 PM CST	Special Weather Statement	SHV	Claiborne	38 min
Jan 21, 6:32 PM CST	Tornado Warning	SHV	Claiborne, Union	43 min
Jan 21, 6:44 PM CST	Tornado Warning	SHV	Claiborne	46 min
Jan 21, 6:48 PM CST	Tornado Warning	SHV	Bossier, Caddo, Webster	57 min
Jan 21, 6:52 PM CST	Severe Thunderstorm Warning	SHV	LaSalle	23 min
Jan 21, 7:00 PM CST	Tornado Warning	SHV	Grant, LaSalle, Winn	22 min
Jan 21, 7:08 PM CST	Tornado Warning	SHV	Grant	52 min
Jan 21, 7:13 PM CST	Tornado Warning	SHV	Union	47 min
Jan 21, 7:34 PM CST	Severe Thunderstorm Warning	SHV	Union	56 min
Jan 21, 7:37 PM CST	Severe Thunderstorm Warning	SHV	Bossier, Claiborne, Webster	68 min
Jan 21, 7:39 PM CST	Tornado Warning	SHV	Union	51 min
Jan 21, 7:56 PM CST	Tornado Warning	SHV	Grant, LaSalle	64 min
Jan 21, 8:03 PM CST	Tornado Warning	SHV	Claiborne, Webster	57 min
Jan 21, 8:21 PM CST	Tornado Warning	SHV	Union	39 min
Jan 21, 8:47 PM CST	Tornado Warning	SHV	Lincoln, Union	43 min
Jan 21, 8:48 PM CST	Special Weather Statement	SHV	Webster	42 min
Jan 21, 6:22 PM CST	Severe Thunderstorm Warning	SHV	Little River, Sevier	53 min
Jan 21, 6:25 PM CST	Severe Thunderstorm Warning	SHV	Howard, Sevier	65 min
Jan 21, 7:33 PM CST	Tornado Warning	SHV	Union	42 min

Nearby

Tornado Warnings in Louisiana, 2017 Tornado Warnings in Arkansas, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.