Alert archive / Louisiana / Tornado Warnings in 2017

Tornado Warning 16, NWS Shreveport, LA

January 21, 2017Grant Parish, Louisiana

NWS Shreveport, LA issued this tornado warning at Jan 21, 2017, 7:08 PM CST for Grant Parish, Louisiana. It was in force for 52 min. 3 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
Jan 21, 2017, 7:08 PM CST (01:08 UTC)
Expired
Jan 21, 2017, 8:00 PM CST
In force
52 min
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Grant Parish, LA

The radar

The Ft Polk radar (KPOE), 61 km from the middle of the area, began a volume at 01:12 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.

What was reported inside it

TimeReportWhereRemark
Jan 21, 7:25 PM CSTHAIL 1Dry Prong, LA1 INCH HAIL IN DRY PRONG.
Jan 21, 7:50 PM CSTHAIL 17 Ssw Georgetown, LA.
Jan 21, 7:51 PM CSTTORNADO10 Ssw Georgetown, LAAN EF1 TORNADO TOUCHED DOWN SOUTH OF GEORGETOWN DOWNING AND/OR SNAPPING NUMEROUS TREES AND POWERLINES. THE TORNADO FIRST TOUCHED DOWN ON HWY. 165 AND MOVED EAST NORTHEAST DAMAGING CAMP HARDTNER. SHINGLES WERE REMOVED FROM SEVERAL STRUCTURES AND A TREE FELL ON

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.

IssuedProductOfficeLasted
Jan 21, 3:41 PM CSTTornado WatchSPC7 hr

The nearest sounding before it

Shreveport, LA (KBAD), launched 00:00Z, 1.1 hours before the alert went out and 144 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 00:00Z on 2017-01-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1144 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 00:00Z on 2017-01-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 200 square meters per square second.19395878Sfc1 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
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.

561 
WFUS54 KSHV 220108
TORSHV
LAC043-220200-
/O.NEW.KSHV.TO.W.0016.170122T0108Z-170122T0200Z/

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

The National Weather Service in Shreveport has issued a

* Tornado Warning for...
  Central Grant Parish in north central Louisiana...

* Until 800 PM CST
    
* At 707 PM CST, a severe thunderstorm capable of producing a tornado
  was located near Colfax, or 9 miles northeast of Lena, moving east
  at 25 mph.

  HAZARD...Tornado. 

  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 tornadic thunderstorm will remain over mainly rural areas of
  central Grant Parish, including the following locations: Aloha, Dry
  Prong, Lake Iatt and Williana.

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.

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

&&

LAT...LON 3153 9273 3158 9278 3164 9272 3171 9258
      3174 9242 3157 9237
TIME...MOT...LOC 0107Z 250DEG 17KT 3159 9271 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

06
1 follow-up statement
360 
WWUS54 KSHV 220151
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
751 PM CST SAT JAN 21 2017

LAC043-220200-
/O.EXP.KSHV.TO.W.0016.000000T0000Z-170122T0200Z/
Grant LA-
751 PM CST SAT JAN 21 2017

...THE TORNADO WARNING FOR CENTRAL GRANT PARISH WILL EXPIRE AT 800 PM
CST...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

A tornado watch remains in effect until 900 PM CST for north central
and northwestern Louisiana.

LAT...LON 3153 9273 3158 9278 3164 9272 3171 9258
      3174 9242 3157 9237
TIME...MOT...LOC 0150Z 250DEG 17KT 3166 9249 

$$

06

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 21, 6:04 PM CSTTornado WarningSHVClaiborne41 min
Jan 21, 6:04 PM CSTTornado WarningSHVBossier, Caddo56 min
Jan 21, 6:13 PM CSTTornado WarningSHVGrant, Winn47 min
Jan 21, 6:14 PM CSTTornado WarningSHVGrant, Natchitoches61 min
Jan 21, 6:16 PM CSTSevere Thunderstorm WarningSHVClaiborne, Webster59 min
Jan 21, 6:22 PM CSTSpecial Weather StatementSHVClaiborne38 min
Jan 21, 6:32 PM CSTTornado WarningSHVClaiborne, Union43 min
Jan 21, 6:44 PM CSTTornado WarningSHVClaiborne46 min
Jan 21, 6:48 PM CSTTornado WarningSHVBossier, Caddo, Webster57 min
Jan 21, 6:52 PM CSTSevere Thunderstorm WarningSHVLaSalle23 min
Jan 21, 7:00 PM CSTTornado WarningSHVGrant, LaSalle, Winn22 min
Jan 21, 7:13 PM CSTTornado WarningSHVUnion47 min
Jan 21, 7:21 PM CSTTornado WarningSHVClaiborne, Union54 min
Jan 21, 7:34 PM CSTSevere Thunderstorm WarningSHVUnion56 min
Jan 21, 7:37 PM CSTSevere Thunderstorm WarningSHVBossier, Claiborne, Webster68 min
Jan 21, 7:39 PM CSTTornado WarningSHVUnion51 min
Jan 21, 7:56 PM CSTTornado WarningSHVGrant, LaSalle64 min
Jan 21, 8:03 PM CSTTornado WarningSHVClaiborne, Webster57 min
Jan 21, 8:21 PM CSTTornado WarningSHVUnion39 min
Jan 21, 8:47 PM CSTTornado WarningSHVLincoln, Union43 min
Jan 21, 8:48 PM CSTSpecial Weather StatementSHVWebster42 min

Nearby

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