Alert archive / Louisiana / Tornado Watches in 2015
Tornado Watch 573
The Storm Prediction Center issued this tornado watch at Dec 27, 2015, 9:57 PM CST for 4 counties in Arkansas; 44 parishes in Louisiana; 11 counties in Mississippi. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 27, 2015, 9:57 PM CST (03:57 UTC)
- Expired
- Dec 28, 2015, 5:00 AM CST
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 59 counties
Ashley County, AR, Chicot County, AR, Columbia County, AR, Union County, AR, Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Iberville Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Livingston Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Saint Helena Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, West Baton Rouge Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Bolivar County, MS, Claiborne County, MS, Franklin County, MS, Issaquena County, MS, Jefferson County, MS, Sharkey County, MS, Warren County, MS, Washington County, MS, Wilkinson County, MS
The radar
The Ft Polk radar (KPOE), 128 km from the middle of the area, began a volume at 04:00 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
- 5%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
40 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 27, 10:04 PM CST | Flash Flood Warning | SHV | Natchitoches, Sabine | 6 hr |
| Dec 27, 10:18 PM CST | Severe Thunderstorm Warning | SHV | Bienville, Caddo, Red River, Webster | 42 min |
| Dec 27, 10:34 PM CST | Severe Thunderstorm Warning | SHV | Claiborne, Webster | 26 min |
| Dec 27, 10:45 PM CST | Severe Thunderstorm Warning | SHV | De Soto, Natchitoches, Red River, Sabine | 30 min |
| Dec 27, 10:52 PM CST | Tornado Warning | SHV | Bienville, Claiborne, Webster | 53 min |
| Dec 27, 10:57 PM CST | Severe Thunderstorm Warning | SHV | Columbia, Lafayette | 23 min |
| Dec 27, 11:10 PM CST | Severe Thunderstorm Warning | SHV | Bienville, Natchitoches, Red River, Webster | 35 min |
| Dec 27, 11:33 PM CST | Severe Thunderstorm Warning | SHV | Bienville, Grant, Jackson, Lincoln, Natchitoches, Red River and 1 more | 57 min |
| Dec 27, 11:42 PM CST | Severe Thunderstorm Warning | SHV | Columbia, Union | 78 min |
| Dec 28, 12:05 AM CST | Tornado Warning | SHV | Bienville, Jackson, Lincoln | 25 min |
| Dec 28, 12:23 AM CST | Flash Flood Warning | SHV | Grant, Jackson, Lincoln, Winn | 4 hr |
| Dec 28, 12:29 AM CST | Severe Thunderstorm Warning | SHV | Union | 61 min |
| Dec 28, 12:42 AM CST | Severe Thunderstorm Warning | JAN | Catahoula, Concordia | 63 min |
| Dec 28, 12:43 AM CST | Severe Thunderstorm Warning | SHV | Union | 32 min |
| Dec 28, 1:23 AM CST | Severe Thunderstorm Warning | JAN | Franklin, Richland | 67 min |
| Dec 28, 1:30 AM CST | Severe Thunderstorm Warning | SHV | Union | 30 min |
| Dec 28, 1:35 AM CST | Tornado Warning | LIX | East Feliciana | 25 min |
| Dec 28, 1:41 AM CST | Severe Thunderstorm Warning | LIX | East Baton Rouge, Iberville, Pointe Coupee, West Baton Rouge | 30 min |
| Dec 28, 1:44 AM CST | Severe Thunderstorm Warning | JAN | Ashley | 76 min |
| Dec 28, 1:44 AM CST | Severe Thunderstorm Warning | JAN | Catahoula, Concordia, Tensas | 61 min |
| Dec 28, 1:51 AM CST | Tornado Warning | LIX | Iberville | 24 min |
| Dec 28, 1:55 AM CST | Severe Thunderstorm Warning | LIX | Ascension, Assumption, Iberville | 50 min |
| Dec 28, 2:02 AM CST | Severe Thunderstorm Warning | LIX | Wilkinson | 28 min |
| Dec 28, 2:17 AM CST | Tornado Warning | LIX | Ascension, East Baton Rouge, Iberville, Livingston | 28 min |
| Dec 28, 2:21 AM CST | Tornado Warning | JAN | Adams, Franklin, Jefferson | 54 min |
| Dec 28, 2:22 AM CST | Severe Thunderstorm Warning | LIX | Ascension, East Baton Rouge, Iberville, Livingston | 38 min |
| Dec 28, 2:24 AM CST | Severe Thunderstorm Warning | LIX | Amite, Wilkinson | 36 min |
| Dec 28, 2:28 AM CST | Tornado Warning | LIX | Livingston, Saint Helena | 47 min |
| Dec 28, 2:35 AM CST | Severe Thunderstorm Warning | LIX | Ascension, Assumption, Livingston, Saint James, Saint John the Baptist | 40 min |
| Dec 28, 2:35 AM CST | Tornado Warning | LIX | Amite | 10 min |
| Dec 28, 2:38 AM CST | Severe Thunderstorm Warning | JAN | Madison, Tensas | 54 min |
| Dec 28, 2:38 AM CST | Tornado Warning | LIX | Amite | 37 min |
| Dec 28, 2:41 AM CST | Tornado Warning | LIX | East Baton Rouge, East Feliciana, Livingston, Saint Helena | 49 min |
| Dec 28, 2:49 AM CST | Severe Thunderstorm Warning | JAN | Ashley, Chicot | 56 min |
| Dec 28, 2:53 AM CST | Tornado Warning | LIX | Livingston, Saint Helena, Tangipahoa | 67 min |
| Dec 28, 3:03 AM CST | Severe Thunderstorm Warning | LIX | Livingston, Saint Helena, Tangipahoa | 57 min |
| Dec 28, 3:06 AM CST | Tornado Warning | LIX | Amite | 24 min |
| Dec 28, 3:11 AM CST | Severe Thunderstorm Warning | JAN | Claiborne, Copiah, Jefferson | 64 min |
| Dec 28, 3:18 AM CST | Tornado Warning | JAN | Franklin, Lincoln | 57 min |
| Dec 28, 3:30 AM CST | Severe Thunderstorm Warning | JAN | Hinds, Issaquena, Warren | 60 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
Shreveport, LA (KBAD), launched 00:00Z, 4.0 hours before the alert went out and 120 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
- 692 J/kg
- Mixed-layer CIN
- -10 J/kg
- Mixed-layer LCL
- 1047 m above ground
- 0-6 km bulk shear
- 61 kt
- 0-1 km storm-relative helicity
- 360 m²/s²
- 0-3 km storm-relative helicity
- 462 m²/s²
- Significant tornado parameter
- 1.9
- Supercell composite
- 9.3
The text
As transmitted, in the capitals the NWS used until 2016.
223 WWUS20 KWNS 280355 SEL3 SPC WW 280355 ARZ000-LAZ000-MSZ000-281100- URGENT - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 573 NWS STORM PREDICTION CENTER NORMAN OK 955 PM CST SUN DEC 27 2015 THE NWS STORM PREDICTION CENTER HAS ISSUED A * TORNADO WATCH FOR PORTIONS OF EXTREME SOUTHERN ARKANSAS MUCH OF LOUISIANA WESTERN MISSISSIPPI * EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 955 PM UNTIL 500 AM CST. * 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 LINE OF STRONG TO OCCASIONALLY SEVERE STORMS IN WESTERN LOUISIANA WILL CONTINUE TO MOVE EASTWARD OVERNIGHT IN ASSOCIATION WITH A COLD FRONT. A COUPLE OF TORNADOES WILL BE POSSIBLE WITH STORMS WITHIN AND AHEAD OF THE LINE...WHILE A FEW DAMAGING GUSTS WILL ALSO BE POSSIBLE WITH STORMS IN THE LINE. THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES EAST NORTHEAST OF EL DORADO ARKANSAS TO 65 MILES SOUTHEAST OF FORT POLK LOUISIANA. 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...THIS TORNADO WATCH REPLACES TORNADO WATCH NUMBER 572. WATCH NUMBER 572 WILL NOT BE IN EFFECT AFTER 955 PM CST. 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 22045. ...THOMPSON
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 27, 7:11 PM CST | Mesoscale Discussion | SPC | Ashley, Bradley, Calhoun, Columbia, Drew, Lafayette and 4 more | 94 min |
| Dec 27, 8:59 PM CST | Mesoscale Discussion | SPC | Ashley, Chicot, Union | 91 min |
| Dec 27, 11:49 PM CST | Mesoscale Discussion | SPC | Ashley, Chicot, Union | 86 min |
| Dec 28, 2:03 AM CST | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Chicot, Desha, Drew and 1 more | 117 min |
| Dec 28, 2:23 AM CST | Tornado Watch | SPC | Lee, Phillips | 8 hr |
| Dec 28, 5:14 AM CST | Mesoscale Discussion | SPC | Crittenden, Cross, Lee, Mississippi, Monroe, Phillips and 3 more | 2 hr |
Nearby
Tornado Watches in Louisiana, 2015Tornado Watches in Mississippi, 2015Tornado Watches in Arkansas, 2015Every tornado watch in 2015
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.