Alert archive / Louisiana / Tornado Watches in 2017
Tornado Watch 83
The Storm Prediction Center issued this tornado watch at Mar 24, 2017, 10:28 PM CDT for 7 parishes in Louisiana; 5 counties in Texas. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 24, 2017, 10:28 PM CDT (03:28 UTC)
- Expired
- Mar 25, 2017, 4:00 AM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
Counties Allen Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Evangeline Parish, LA, Jefferson Davis Parish, LA, Rapides Parish, LA, Vernon Parish, LA, Hardin County, TX, Jasper County, TX, Newton County, TX, Orange County, TX, Tyler County, TX
The radar
The Ft Polk radar (KPOE), 51 km from the middle of the area, began a volume at 03:32 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 24, 10:41 PM CDT | Tornado Warning | LCH | Jasper, Tyler | 19 min |
| Mar 24, 10:57 PM CDT | Severe Thunderstorm Warning | LCH | Jasper, Tyler | 33 min |
| Mar 24, 11:21 PM CDT | Severe Thunderstorm Warning | LCH | Jasper, Newton, Tyler | 54 min |
| Mar 24, 11:40 PM CDT | Severe Thunderstorm Warning | LCH | Hardin, Jasper, Tyler | 65 min |
| Mar 25, 12:13 AM CDT | Severe Thunderstorm Warning | LCH | Beauregard, Vernon | 36 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 00:00Z, 3.5 hours before the alert went out and 89 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.
- Mixed-layer CAPE
- 762 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 666 m above ground
- 0-6 km bulk shear
- 52 kt
- 0-1 km storm-relative helicity
- 156 m²/s²
- 0-3 km storm-relative helicity
- 230 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 3.4
The text
As transmitted.
764 WWUS20 KWNS 250326 SEL3 SPC WW 250326 LAZ000-TXZ000-250900- URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 83 NWS Storm Prediction Center Norman OK 1030 PM CDT Fri Mar 24 2017 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southwest Louisiana Southeast Texas * Effective this Friday night and Saturday morning from 1030 PM until 400 AM CDT. * Primary threats include... A couple tornadoes possible Isolated damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...A band of severe thunderstorms will spread eastward from southeast Texas into southwest Louisiana through the overnight hours. The strongest storms within the band could have supercell structures, with an attendant risk for a couple of tornadoes. Otherwise, damaging winds and isolated large hail will be possible. The tornado watch area is approximately along and 50 statute miles east and west of a line from 25 miles north northeast of Fort Polk LA to 65 miles south southwest of Fort Polk LA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 80...WW 81...WW 82... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 26035. ...Thompson
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 24, 8:39 PM CDT | Mesoscale Discussion | SPC | Bienville, Bossier, Caddo, Claiborne, De Soto, Red River and 1 more | 66 min |
| Mar 24, 9:14 PM CDT | Severe Thunderstorm Watch | SPC | Bienville, Bossier, Caddo, Claiborne, Jackson, Lincoln and 3 more | 6 hr |
| Mar 24, 9:23 PM CDT | Tornado Watch | SPC | Caldwell, De Soto, Grant, LaSalle, Natchitoches, Red River and 2 more | 6 hr |
| Mar 24, 9:58 PM CDT | Mesoscale Discussion | SPC | Allen, Beauregard, Calcasieu, Evangeline, Jefferson Davis, Rapides and 2 more | 62 min |
| Mar 24, 11:41 PM CDT | Mesoscale Discussion | SPC | Avoyelles, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 7 more | 64 min |
| Mar 25, 12:05 AM CDT | Severe Thunderstorm Watch | SPC | Catahoula, Concordia, East Carroll, Franklin, Madison, Morehouse and 3 more | 5 hr |
| Mar 25, 2:08 AM CDT | Mesoscale Discussion | SPC | Acadia, Allen, Beauregard, Calcasieu, Cameron, Evangeline and 6 more | 67 min |
| Mar 25, 3:06 AM CDT | Mesoscale Discussion | SPC | Catahoula, Concordia, East Carroll, Franklin, Madison, Richland and 1 more | 54 min |
| Mar 25, 5:25 AM CDT | Mesoscale Discussion | SPC | Allen, Beauregard, Calcasieu, Vernon | 2 hr |
| Mar 25, 12:08 PM CDT | Mesoscale Discussion | SPC | Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 1 more | 3 hr |
| Mar 24, 7:07 PM CDT | Tornado Watch | SPC | Angelina, Austin, Brazos, Burleson, Cherokee, Colorado and 20 more | 5 hr |
Nearby
Tornado Watches in Louisiana, 2017Tornado Watches in Texas, 2017Every tornado watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.