Alert archive / Louisiana / Mesoscale Discussions in 2016
Mesoscale Discussion 296
The Storm Prediction Center issued this mesoscale discussion at Mar 30, 2016, 8:39 PM CDT for 7 counties in Arkansas; 19 parishes in Louisiana; 4 counties in Mississippi. It was in force for 96 min.
The area
The outline as issued.
The facts
- Issued
- Mar 30, 2016, 8:39 PM CDT (01:39 UTC)
- Expired
- Mar 30, 2016, 10:15 PM CDT
- In force
- 96 min
- Issued by
- the Storm Prediction Center
All 30 counties
Ashley County, AR, Bradley County, AR, Chicot County, AR, Desha County, AR, Drew County, AR, Lincoln County, AR, Union County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Bolivar County, MS, Issaquena County, MS, Sharkey County, MS, Washington County, MS
The radar
The Shreveport radar (KSHV), 152 km from the middle of the area, began a volume at 01:43 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Shreveport, LA (KBAD), launched 00:00Z, 1.7 hours before the alert went out and 143 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
- 1333 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 683 m above ground
- 0-6 km bulk shear
- 54 kt
- 0-1 km storm-relative helicity
- 246 m²/s²
- 0-3 km storm-relative helicity
- 250 m²/s²
- Significant tornado parameter
- 2.5
- Supercell composite
- 10.4
The text
As transmitted.
671
ACUS11 KWNS 310139
SWOMCD
SPC MCD 310139
MSZ000-ARZ000-LAZ000-TXZ000-310315-
MESOSCALE DISCUSSION 0296
NWS STORM PREDICTION CENTER NORMAN OK
0839 PM CDT WED MAR 30 2016
AREAS AFFECTED...NRN LA..SERN AR...FAR WRN MS
CONCERNING...TORNADO WATCH 60...63...
VALID 310139Z - 310315Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 60...63...CONTINUES.
SUMMARY...PARTS OF TORNADO WATCH 60 MAY BE REPLACED WITH A NEW
TORNADO WATCH PRIOR TO 03Z SCHEDULED EXPIRATION FOR A PERSISTENT
LONG-DURATION/LOW-PROBABILITY TORNADO RISK.
DISCUSSION...SEVERAL CONVECTIVE CLUSTERS ARE ONGOING WITHIN A
BROADER CONVECTIVE MASS FROM THE MID-SOUTH SWWD TO NE TX. 00Z SHV
RAOB SAMPLED A RELATIVELY FAVORABLE TORNADO ENVIRONMENT WITH MLCAPE
AROUND 1500 J/KG AND 0-1 KM SRH AROUND 200-250 M2/S2. HOWEVER...THE
MESSY CLUSTER CONVECTIVE MODE HAS GENERALLY YIELDED TRANSIENT
EMBEDDED SUPERCELL STRUCTURES. THIS TYPE OF MODE WILL LIKELY PERSIST
INTO THE OVERNIGHT GIVEN REGENERATIVE CONVECTION OCCURRING WITHIN
PRE-FRONTAL CONFLUENCE BANDS. THE PRIMARY TORNADO THREAT AREA SHOULD
SHIFT SLOWLY E AS LOW-LEVEL WINDS BECOMES INCREASINGLY VEERED /A
PROCESS THAT APPEARS TO BE UNDERWAY FROM THE SHV AREA WWD PER VWP
DATA/. THE COMPARATIVELY LONGEST DURATION TORNADO RISK WILL PROBABLY
BE CENTERED ALONG THE SERN PORTION OF THE LARGE-SCALE CONVECTIVE
PLUME /OVER THE ARK-LA-MISS REGION/ INTO THE OVERNIGHT.
..GRAMS/CORFIDI.. 03/31/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MEG...JAN...LZK...SHV...
LAT...LON 32319413 32719384 33139295 33559234 34189146 34219116
34079081 33559062 32969065 32529079 32109159 31859257
31829350 31899395 32319413SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 30, 7:44 PM CDT | Severe Thunderstorm Watch | SPC | Benton | 4 hr |
| Mar 30, 8:37 PM CDT | Mesoscale Discussion | SPC | Benton | 53 min |
| Mar 30, 10:00 PM CDT | Tornado Watch | SPC | Ashley, Bradley, Chicot, Desha, Drew, Union | 6 hr |
| Mar 30, 11:30 PM CDT | Mesoscale Discussion | SPC | Chicot, Desha | 60 min |
| Mar 31, 10:26 AM CDT | Mesoscale Discussion | SPC | Arkansas, Cleveland, Craighead, Crittenden, Cross, Dallas and 14 more | 3 hr |
| Mar 31, 10:58 AM CDT | Severe Thunderstorm Watch | SPC | Clay, Craighead, Crittenden, Cross, Greene, Jackson and 9 more | 5 hr |
| Mar 31, 1:30 PM CDT | Mesoscale Discussion | SPC | Chicot | 2 hr |
| Mar 31, 2:05 PM CDT | Severe Thunderstorm Watch | SPC | Arkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 7 more | 8 hr |
| Mar 31, 2:14 PM CDT | Mesoscale Discussion | SPC | Crittenden, Cross | 91 min |
| Mar 31, 2:35 PM CDT | Tornado Watch | SPC | Lee, Phillips | 7 hr |
| Mar 31, 3:04 AM CDT | Mesoscale Discussion | SPC | East Feliciana, Pointe Coupee, Saint Helena, Tangipahoa, Washington, West Feliciana | 86 min |
| Mar 31, 3:20 AM CDT | Tornado Watch | SPC | East Baton Rouge, East Feliciana, Livingston, Pointe Coupee, Saint Helena, Saint Tammany and 4 more | 6 hr |
| Mar 31, 3:30 PM CDT | Mesoscale Discussion | SPC | Ascension, East Baton Rouge, East Feliciana, Iberville, Livingston, Pointe Coupee and 6 more | 2 hr |
| Mar 31, 5:22 PM CDT | Mesoscale Discussion | SPC | Caldwell, Catahoula, East Carroll, Franklin, Grant, Jackson and 9 more | 53 min |
| Mar 31, 7:47 AM CDT | Mesoscale Discussion | SPC | Covington, Forrest, Greene, Jefferson Davis, Jones, Lamar and 3 more | 58 min |
| Mar 31, 8:43 AM CDT | Tornado Watch | SPC | George, Greene, Perry, Stone | 5 hr |
| Mar 31, 4:47 PM CDT | Mesoscale Discussion | SPC | Alcorn, Attala, Benton, Bolivar, Calhoun, Carroll and 55 more | 58 min |
| Mar 31, 5:58 PM CDT | Tornado Watch | SPC | Wayne | 7 hr |
| Mar 31, 6:52 PM CDT | Mesoscale Discussion | SPC | Alcorn, Calhoun, Chickasaw, Choctaw, Clarke, Clay and 29 more | 53 min |
Nearby
Mesoscale Discussions in Louisiana, 2016Mesoscale Discussions in Arkansas, 2016Mesoscale Discussions in Mississippi, 2016Every mesoscale discussion 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.