Alert archive / Louisiana / Mesoscale Discussions in 2016
Mesoscale Discussion 236
The Storm Prediction Center issued this mesoscale discussion at Mar 18, 2016, 1:16 PM CDT for 4 states. It was in force for 59 min.
The area
The outline as issued.
The facts
- Issued
- Mar 18, 2016, 1:16 PM CDT (18:16 UTC)
- Expired
- Mar 18, 2016, 2:15 PM CDT
- In force
- 59 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 95%
All 53 counties
Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Columbia County, AR, Drew County, AR, Hempstead County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita 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, Tensas Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Claiborne County, MS, Hinds County, MS, Humphreys County, MS, Issaquena County, MS, Madison County, MS, Rankin County, MS, Sharkey County, MS, Warren County, MS, Washington County, MS, Yazoo County, MS, Bowie County, TX, Camp County, TX, Cass County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Morris County, TX, Panola County, TX, Titus County, TX, Upshur County, TX
The radar
The Shreveport radar (KSHV), 106 km from the middle of the area, began a volume at 18:18 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 12:00Z, 6.3 hours before the alert went out and 97 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
- 11 J/kg
- Mixed-layer CIN
- -466 J/kg
- Mixed-layer LCL
- 489 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 191 m²/s²
- 0-3 km storm-relative helicity
- 245 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
128
ACUS11 KWNS 181817
SWOMCD
SPC MCD 181816
MSZ000-ARZ000-LAZ000-TXZ000-OKZ000-181915-
MESOSCALE DISCUSSION 0236
NWS STORM PREDICTION CENTER NORMAN OK
0116 PM CDT FRI MAR 18 2016
AREAS AFFECTED...NORTHEAST TEXAS...SOUTHERN ARKANSAS...NORTHERN
LOUISIANA ...AND WEST-CENTRAL MISSISSIPPI
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 181816Z - 181915Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...LARGE HAIL AND ISOLATED SEVERE WIND GUSTS WILL BE POSSIBLE
THROUGH THE AFTERNOON. A SEVERE THUNDERSTORM WATCH IS LIKELY.
DISCUSSION...ISOLATED-TO-SCATTERED ELEVATED THUNDERSTORMS WILL
CONTINUE TO DEVELOP ACROSS PORTIONS OF NORTHERN LOUISIANA WITHIN A
BAND OF WEAK WARM-AIR ADVECTION ATOP A WEAKLY-STABLE BOUNDARY LAYER.
FORECAST SOUNDINGS SUGGEST THESE THUNDERSTORMS ARE ROOTED WITHIN THE
850-700MB LAYER...WITH STEEP LAPSE RATES ABOVE RESULTING IN A
RESERVOIR OF ELEVATED CAPE ON THE ORDER OF 500-1500
JOULES-PER-KILOGRAM. GIVEN THE EXPECTED ELEVATED NATURE OF THE
THUNDERSTORMS...LARGE HAIL APPEARS TO BE THE PRIMARY
THREAT...ALTHOUGH AN ISOLATED WIND GUST APPROACHING SEVERE LIMITS
CANNOT BE RULED OUT. THESE THUNDERSTORMS WILL CONTINUE TO MOVE
GENERALLY EASTWARD THROUGH THE AFTERNOON.
TO THE NORTHWEST...ONGOING THUNDERSTORM/S WITH A HISTORY OF
PRODUCING SPORADIC LARGE HAIL REPORTS WILL CONTINUE TO MOVE EAST.
GIVEN NO APPRECIABLE CHANGE IN THE ENVIRONMENT AHEAD OF THESE
STORMS...THE THREAT FOR LARGE HAIL AND ISOLATED SEVERE WIND GUSTS
SHOULD PERSIST THROUGH THE AFTERNOON.
CURRENT ENVIRONMENTAL AND RADAR TRENDS SUGGEST A SEVERE THUNDERSTORM
WATCH WILL BECOME NECESSARY.
..MARSH/WEISS.. 03/18/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...JAN...LZK...SHV...
LAT...LON 32469516 33509509 33839469 34049327 33689110 32938981
32388977 32039029 31909150 31749300 31999430 32469516SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 18, 9:51 AM CDT | Mesoscale Discussion | SPC | Clark, Columbia, Garland, Hempstead, Hot Spring, Howard and 8 more | 84 min |
| Mar 18, 1:35 PM CDT | Severe Thunderstorm Watch | SPC | Ashley, Bradley, Calhoun, Chicot, Columbia, Drew and 7 more | 6 hr |
| Mar 18, 3:47 PM CDT | Mesoscale Discussion | SPC | Ashley, Bradley, Calhoun, Chicot, Columbia, Drew and 7 more | 118 min |
| Mar 18, 10:40 AM CDT | Mesoscale Discussion | SPC | Ascension, Assumption, Jefferson, Lafourche, Orleans, Plaquemines and 7 more | 95 min |
| Mar 18, 6:04 AM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Clay, Collin, Cooke, Cottle and 10 more | 2 hr |
| Mar 18, 1:57 PM CDT | Mesoscale Discussion | SPC | Bandera, Crockett, Edwards, Gillespie, Kendall, Kerr and 8 more | 2 hr |
| Mar 18, 4:09 PM CDT | Severe Thunderstorm Watch | SPC | Atascosa, Bandera, Bastrop, Bell, Bexar, Blanco and 31 more | 7 hr |
| Mar 18, 6:05 PM CDT | Mesoscale Discussion | SPC | Atascosa, Bandera, Bastrop, Bell, Bexar, Blanco and 23 more | 55 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.