Alert archive / Louisiana / Tornado Watches in 2016

Tornado Watch 5

January 21, 201618 parishes in Louisiana; 14 counties in Texas

The Storm Prediction Center issued this tornado watch at Jan 21, 2016, 11:48 AM CST for 18 parishes in Louisiana; 14 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jan 21, 2016, 11:48 AM CST (17:48 UTC)
Expired
Jan 21, 2016, 5:05 PM CST
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 32 counties

Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Evangeline Parish, LA, Grant Parish, LA, Jefferson Davis Parish, LA, LaSalle Parish, LA, Natchitoches Parish, LA, Rapides Parish, LA, Sabine Parish, LA, Saint Landry Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Winn Parish, LA, Angelina County, TX, Chambers County, TX, Hardin County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Nacogdoches County, TX, Newton County, TX, Orange County, TX, Polk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Tyler County, TX

The radar

The Ft Polk radar (KPOE), 73 km from the middle of the area, began a volume at 17:51 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
70%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jan 21, 12:02 PM CSTTornado WarningLCHJasper, Newton43 min
Jan 21, 12:04 PM CSTTornado WarningLCHJasper, Tyler25 min
Jan 21, 12:34 PM CSTSevere Thunderstorm WarningLCHJasper, Newton41 min
Jan 21, 12:43 PM CSTTornado WarningLCHBeauregard38 min
Jan 21, 1:05 PM CSTSevere Thunderstorm WarningLCHVernon40 min
Jan 21, 1:13 PM CSTSevere Thunderstorm WarningSHVGrant, Natchitoches, Sabine, Winn47 min
Jan 21, 1:17 PM CSTTornado WarningSHVNatchitoches, Sabine28 min
Jan 21, 1:19 PM CSTSevere Thunderstorm WarningLCHBeauregard41 min
Jan 21, 1:55 PM CSTSevere Thunderstorm WarningLCHAllen, Beauregard, Rapides, Vernon50 min
Jan 21, 2:05 PM CSTSevere Thunderstorm WarningSHVLaSalle25 min
Jan 21, 2:08 PM CSTSevere Thunderstorm WarningLCHAvoyelles37 min
Jan 21, 2:18 PM CSTTornado WarningLCHAvoyelles27 min
Jan 21, 2:41 PM CSTSevere Thunderstorm WarningLCHAvoyelles, Rapides, Vernon49 min
Jan 21, 2:49 PM CSTSevere Thunderstorm WarningLCHAvoyelles26 min
Jan 21, 3:31 PM CSTSevere Thunderstorm WarningLCHAvoyelles, Rapides44 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 5.8 hours before the alert went out and 112 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, Lake Charles Mun, LA at 12:00Z on 2016-01-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1051 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, Lake Charles Mun, LA at 12:00Z on 2016-01-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 192 square meters per square second.1939587897Sfc1 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
1051 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
548 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
192 m²/s²
0-3 km storm-relative helicity
215 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.2

Open this sounding in Storm Lab

The text

As transmitted.

459 
WWUS20 KWNS 211746
SEL5  
SPC WW 211746
LAZ000-TXZ000-CWZ000-220100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 5
NWS STORM PREDICTION CENTER NORMAN OK
1150 AM CST THU JAN 21 2016

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  PARTS OF WESTERN AND CENTRAL LOUISIANA
  PARTS OF EAST CENTRAL AND SOUTHEAST TEXAS
  COASTAL WATERS

* EFFECTIVE THIS THURSDAY MORNING AND EVENING FROM 1150 AM UNTIL
  700 PM CST.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES LIKELY
  SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2
    INCHES IN DIAMETER POSSIBLE
  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

SUMMARY...SCATTERED-NUMEROUS THUNDERSTORMS WILL CONTINUE TO FORM AND
INTENSIFY FROM EAST TEXAS INTO LOUISIANA THROUGH THE AFTERNOON.  THE
STRONGEST STORMS WILL POSE A RISK FOR A FEW TORNADOES...IN ADDITION
TO LARGE HAIL AND DAMAGING WINDS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE
MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHWEST OF
NATCHITOCHES LOUISIANA TO 30 MILES SOUTHEAST OF PORT ARTHUR
TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 24030.


...THOMPSON

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 21, 4:40 AM CSTMesoscale DiscussionSPCAllen, Beauregard, Bienville, Caddo, De Soto, Grant and 8 more95 min
Jan 21, 10:59 AM CSTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Beauregard, Calcasieu, Evangeline and 7 more2 hr
Jan 21, 1:44 PM CSTMesoscale DiscussionSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 29 more2 hr
Jan 21, 2:14 PM CSTTornado WatchSPCAscension, Assumption, Catahoula, Concordia, East Baton Rouge, East Feliciana and 23 more6 hr
Jan 21, 4:57 PM CSTMesoscale DiscussionSPCEast Feliciana, Saint Helena63 min

Nearby

Tornado Watches in Louisiana, 2016Tornado Watches in Texas, 2016Every tornado watch in 2016

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.