Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 300442
SWOMCD
SPC MCD 300442
LAZ000-ARZ000-TXZ000-300615-

MESOSCALE DISCUSSION 0508
NWS STORM PREDICTION CENTER NORMAN OK
1142 PM CDT FRI APR 29 2016

AREAS AFFECTED...ARKLATEX

CONCERNING...SEVERE THUNDERSTORM WATCH 127...128...

VALID 300442Z - 300615Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
127...128...CONTINUES.

SUMMARY...THE RISK FOR STRONG SURFACE GUSTS AND PERHAPS ISOLATED
TORNADOES IS EXPECTED TO CONTINUE INTO THE 06-09Z TIME
FRAME...GRADUALLY SHIFTING EAST OF THE ARKLATEX /AND THE SHREVEPORT
AREA/.  AREAS EAST OF WATCH 128 WILL BE MONITORED FOR THE
POSSIBILITY OF AN ADDITIONAL WATCH.

DISCUSSION...A LARGE AREA OF THUNDERSTORM ACTIVITY
CONTINUES...ROUGHLY CENTERED ACROSS OR JUST TO THE SOUTHWEST OF THE
ARKLATEX REGION.  THIS APPEARS GENERALLY FOCUSED BENEATH STRONGEST
HIGH LEVEL DIVERGENCE...WITHIN A ZONE OF BROAD UPPER DIFLUENCE
EXTENDING EAST NORTHEASTWARD OUT OF THE LOWER RIO GRANDE VALLEY.  A
BROAD BELT OF 40-50 KT SOUTHERLY 850 MB FLOW ACROSS UPPER TEXAS AND
LOUISIANA COASTAL AREAS INTO THE OZARK PLATEAU IS ALSO ENHANCING
LOW-LEVEL WARM ADVECTION ACROSS THIS REGION.  IT APPEARS THAT THIS
MAY PERSIST ANOTHER SEVERAL HOURS...AT LEAST THROUGH THE 06-08Z TIME
FRAME.

SOUTHEASTERLY NEAR SURFACE FLOW TO THE NORTH OF A BOUNDARY GENERATED
BY PERSISTENT CONVECTION IS CONTRIBUTING TO VERY LARGE AND CLOCKWISE
CURVED LOW-LEVEL HODOGRAPHS ACROSS AND SOUTH THROUGH WEST OF THE
SHREVEPORT AREA.  THIS HAS BEEN SUFFICIENT TO SUPPORT OCCASIONAL
DEVELOPMENT AND INTENSIFICATION OF LOW-LEVEL MESOCYCLONES WITH THE
MORE DISCRETE STRONGER CORES ACROSS THE ARKLATEX DURING THE PAST
HOUR OR TWO.

AS THESE CELLS TRACK NORTHWARD ABOVE A SLIGHTLY COOLER AND MORE
STABLE BOUNDARY LAYER TO THE NORTH OF THE ARKANSAS/LOUISIANA
BORDER...POTENTIAL FOR TORNADOES SEEMS LIKELY TO DIMINISH.
HOWEVER...IN CLOSER PROXIMITY TO THE CONVECTIVE BOUNDARY ACROSS
NORTHERN LOUISIANA...WHERE SURFACE TEMPERATURES ARE IN MID 70S AND
DEW POINTS AROUND 70F...POTENTIAL FOR BRIEF TORNADOES...OR AT LEAST
LOCALIZED STRONG SURFACE GUSTS MAY CONTINUE.  AS THE LOW-LEVEL JET
SHIFTS TOWARD THE MISSISSIPPI RIVER OVERNIGHT...THIS PROBABLY WILL
GRADUALLY SHIFT EAST OF THE SHREVEPORT AREA THROUGH 07-09Z.

..KERR.. 04/30/2016

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

ATTN...WFO...JAN...LZK...SHV...FWD...

LAT...LON   32049267 32249194 33459205 33749337 33719431 32869543
            32049472 31989377 32049267




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