Alert archive / Louisiana / Tornado Watches in 2013
Tornado Watch 1
The Storm Prediction Center issued this tornado watch at Jan 10, 2013, 4:31 AM CST for 22 parishes in Louisiana; 5 counties in Mississippi. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 10, 2013, 4:31 AM CST (10:31 UTC)
- Expired
- Jan 10, 2013, 10:09 AM CST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
All 27 counties
Acadia Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Livingston Parish, LA, Pointe Coupee Parish, LA, Saint Helena Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, St. Mary Parish, LA, Vermilion Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Franklin County, MS, Jefferson County, MS, Wilkinson County, MS
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
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 10, 4:34 AM CST | Tornado Warning | LCH | Evangeline, Saint Landry | 26 min |
| Jan 10, 5:04 AM CST | Tornado Warning | LCH | Avoyelles, Saint Landry | 26 min |
| Jan 10, 5:34 AM CST | Flash Flood Warning | JAN | Claiborne, Issaquena, Jefferson, Sharkey, Warren, Yazoo | 6 hr |
| Jan 10, 5:44 AM CST | Flash Flood Warning | SHV | Caldwell, Grant, LaSalle, Natchitoches, Winn | 3 hr |
| Jan 10, 5:48 AM CST | Severe Thunderstorm Warning | LCH | Iberia, Saint Martin, St. Mary | 27 min |
| Jan 10, 6:24 AM CST | Severe Thunderstorm Warning | LCH | Iberia, Saint Martin, St. Mary | 36 min |
| Jan 10, 6:45 AM CST | Tornado Warning | JAN | Concordia | 45 min |
| Jan 10, 7:36 AM CST | Severe Thunderstorm Warning | JAN | Claiborne, Franklin, Jefferson | 54 min |
| Jan 10, 7:46 AM CST | Tornado Warning | LIX | East Baton Rouge, Iberville | 29 min |
| Jan 10, 7:50 AM CST | Tornado Warning | LIX | Ascension, East Baton Rouge | 25 min |
| Jan 10, 8:15 AM CST | Tornado Warning | LIX | Ascension, East Baton Rouge, Livingston | 30 min |
| Jan 10, 8:17 AM CST | Flash Flood Warning | LIX | Ascension, Assumption, Iberville, Lafourche, Livingston, Saint James and 1 more | 5 hr |
| Jan 10, 8:54 AM CST | Flash Flood Warning | LIX | Assumption, Lafourche, Terrebonne | 4 hr |
| Jan 10, 9:19 AM CST | Flash Flood Warning | JAN | Claiborne, Copiah, Franklin, Jefferson, Lincoln | 116 min |
| Jan 10, 9:46 AM CST | Flash Flood Warning | JAN | Catahoula, Concordia, Franklin, Tensas | 3 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 00:00Z, 10.5 hours before the alert went out and 198 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
- 196 J/kg
- Mixed-layer CIN
- -10 J/kg
- Mixed-layer LCL
- 447 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 225 m²/s²
- 0-3 km storm-relative helicity
- 292 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
The text
As transmitted, in the capitals the NWS used until 2016.
762
WWUS20 KWNS 101035
SEL1
SPC WW 101035
LAZ000-MSZ000-CWZ000-101800-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 1
NWS STORM PREDICTION CENTER NORMAN OK
435 AM CST THU JAN 10 2013
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
CENTRAL LOUISIANA
SOUTHWEST MISSISSIPPI
COASTAL WATERS
EFFECTIVE THIS THURSDAY MORNING FROM 435 AM UNTIL NOON CST.
TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE
MILES EAST AND WEST OF A LINE FROM 10 MILES NORTH OF NATCHEZ
MISSISSIPPI TO 40 MILES SOUTH SOUTHEAST OF INTRACOASTAL CITY
LOUISIANA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).
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.
DISCUSSION...EXISTING SSW-NNE SQLN HAS SHOWN SOME SIGNS OF
PERSISTENT STRENGTHENING IN THE PAST HOUR. THIS MAY BE DUE TO /1/
ARRIVAL OF DEEPER/STRONGER LOW-LVL WLY FLOW TO ITS LEADING EDGE /PER
LCH VWP/...AND /2/ TO PERHAPS INCREASED LARGE SCALE ASCENT NEARING
REGION /PER WATER VAPOR IMAGERY./ AT ANY RATE...AREA VWP DATA SHOW
AMPLE LOW-LVL SHEAR TO SUPPORT LOW-LVL MESO/POSSIBLE TORNADOES GIVEN
PERSISTENT ESELY SFC WINDS E OF SQLN LINE. ALSO...REGION IS
SUFFICIENTLY MOIST /DEWPOINTS IN THE UPR 60S TO AROUND 70F/ TO
SUPPORT SUSTAINED UPDRAFTS...DESPITE RELATIVELY WEAK MID-LVL LAPSE
RATES....GIVEN PRESENCE OF A SOURCE FOR LOW-LVL UPLIFT ALONG SQLN
GUST FRONT.
OVERALL SETUP SUGGESTS A POSSIBLY INCREASING RISK FOR EMBEDDED
LEWPS/ROTATING STRUCTURES CAPABLE OF TORNADOES/LOCALLY DMGG WIND AS
THE SQLN DEVELOPS FARTHER NNEWD...AND MOVES GENERALLY
ENEWD...THROUGH LATER THIS MORNING.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
400. MEAN STORM MOTION VECTOR 21030.
...CORFIDISPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 9, 6:18 PM CST | Mesoscale Discussion | SPC | Assumption, Iberia, Jefferson, Lafourche, Orleans, Plaquemines and 5 more | 117 min |
| Jan 10, 4:05 AM CST | Mesoscale Discussion | SPC | Acadia, Avoyelles, Concordia, Evangeline, Iberia, Iberville and 7 more | 85 min |
| Jan 10, 5:47 AM CST | Mesoscale Discussion | SPC | Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 4 more | 58 min |
| Jan 10, 6:14 AM CST | Tornado Watch | SPC | Ascension, Assumption, Concordia, East Baton Rouge, East Feliciana, Iberville and 17 more | 11 hr |
| Jan 10, 7:36 AM CST | Mesoscale Discussion | SPC | Ascension, Assumption, East Baton Rouge, East Feliciana, Jefferson, Lafourche and 12 more | 84 min |
| Jan 10, 11:35 AM CST | Mesoscale Discussion | SPC | Orleans, Plaquemines, Saint Bernard | 85 min |
| Jan 10, 5:40 PM CST | Mesoscale Discussion | SPC | Tunica | 2 hr |
Nearby
Tornado Watches in Louisiana, 2013Tornado Watches in Mississippi, 2013Every tornado watch in 2013
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.