Severe Storm Outlook Narrative (AC)
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
293
ACUS11 KWNS 300933
SWOMCD
SPC MCD 300933
ALZ000-MSZ000-LAZ000-301100-

MESOSCALE DISCUSSION 1854
NWS STORM PREDICTION CENTER NORMAN OK
0333 AM CST WED NOV 30 2016

AREAS AFFECTED...SOUTH-CENTRAL AND SOUTHEASTERN LA...SOUTHERN AND
EAST-CENTRAL MS

CONCERNING...TORNADO WATCH 508

VALID 300933Z - 301100Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 508 CONTINUES.

SUMMARY...ISOLATED DAMAGING WINDS WILL BE THE PRIMARY THREAT AND
WILL PREFERENTIALLY OCCUR WITH STRONGER EMBEDDED CORES AND
STORM-SCALE BOWING SEGMENTS WITHIN THE QLCS.  A CONDITIONAL THREAT
FOR A SHORT-LIVED/WEAK TORNADO CONTINUES OVER LA --MAINLY NORTH OF
I-10-- AND SOUTHERN MS.

DISCUSSION...RADAR MOSAIC SHOWS AN EXTENSIVE SOUTHWEST-TO-NORTHEAST
ALIGNED QLCS FROM 40 MI SOUTHEAST OF LCH...TO 20 MI WEST NORTHWEST OF
MCB...TO 45 MI SOUTHWEST OF CBM.  0-3 KM SHEAR VECTORS ARE LARGELY
PARALLEL TO THE QLCS ORIENTATION AND ARE CONSIDERED RELATIVELY WEAK
FOR APPRECIABLE MESOVORTEX POTENTIAL.  NONETHELESS...DEEPER
REFLECTIVITY CORES EMBEDDED WITHIN THE LA PORTION OF THE QLCS IMPLY
THAT UPDRAFTS ARE STILL STRONG AND WILL LIKELY ASSOCIATE WITH THE
STRONGER DOWNDRAFTS.  LOCALIZED DAMAGING WINDS MAY RESULT FROM SOME
OF THE STRONGER WATER-LOADED DOWNDRAFTS TRANSPORTING STRONGER FLOW
ALOFT TO THE SURFACE.

A CONDITIONAL BUT POTENTIALLY GREATER HAZARD MAY OCCUR IF ONE OR
MORE UPDRAFTS CAN OPPORTUNISTICALLY BECOME RELATIVELY LESS
INFLUENCED BY COLD-POOL PROCESSES AND TEMPORALLY ACQUIRE LOW- TO
MID-LEVEL ROTATION.  IF THIS WERE TO OCCUR...THE RISK FOR A
WEAK/SHORT-LIVED TORNADO COULD DEVELOP.

A FEW SHALLOW STORMS NEAR THE SOUTHEASTERN MS/SOUTHWESTERN AL BORDER
HAVE ACQUIRED TRANSIENT WEAK ROTATION DURING THE PAST HOUR.  THIS
AREA WILL CONTINUE TO BE MONITORED FOR ADDITIONAL STORM-SCALE
STRENGTHENING OVER THE NEXT 30-60 MINUTES.

GIVEN THE CONDITIONAL YET FAVORABLE BACKGROUND MESOSCALE ENVIRONMENT
FROM A PARAMETER-SPACE STANDPOINT --REFERENCE 06 UTC LIX RAOB-- A
LOWER-PROBABILITY TIER TORNADO WATCH WILL PROBABLY BE NEEDED TO THE
EAST OF THE QLCS ACROSS SOUTHEASTERN LA...SOUTHERN MS...SOUTHWESTERN
AL...AND PERHAPS THE WESTERN FL PANHANDLE PRIOR TO THE EXPIRATION
TIME OF 11 UTC FOR TORNADO WATCH 508.

..SMITH.. 11/30/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...BMX...MOB...JAN...LIX...LCH...

LAT...LON   29659261 33428830 31588846 30408947 29149100 29659261




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.