SPC MD 2024

MD 2024 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR LA/SRN MS

MESOSCALE DISCUSSION 2024
NWS STORM PREDICTION CENTER NORMAN OK
0547 PM CST MON DEC 21 2015

AREAS AFFECTED...LA/SRN MS

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 212347Z - 220145Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...LIMITED SEVERE RISK -- INCLUDING POTENTIAL FOR A BRIEF
TORNADO OR TWO -- WILL LIKELY PERSIST OVER THE NEXT SEVERAL HOURS. 
THE RISK SHOULD SHIFT FROM WRN AND CENTRAL LA EWD INTO SRN MS/SERN
LA/SRN AL AND EVENTUALLY THE WRN FL PANHANDLE WITH TIME. 
HOWEVER...WW ISSUANCE APPEARS UNNECESSARY ATTM DUE TO WHAT APPEARS
TO REMAIN A LOCALIZED/LIMITED THREAT IN THE WRN/CENTRAL LA AREA.

DISCUSSION...LATEST RADAR LOOP SHOWS A COUPLE OF COMPACT/ROTATING
STORMS MOVING ACROSS CENTRAL LA ATTM...WITH ONE OF THE CELLS
POSSIBLY HAVING PRODUCED A TORNADO OVER THE PAST HOUR.  THE STORMS
CONTINUE MOVING ENEWD...AND WITH H8 WARM ADVECTION /AND THUS
INCREASED CAPPING/ SPREADING NEWD...STORM DEVELOPMENT UPSTREAM OF
ONGOING CONVECTION IS NOT EXPECTED.

WITH TIME...THE EXISTING CENTRAL LA STORMS WILL ENCOUNTER A LESS
UNSTABLE DOWNSTREAM AIRMASS INTO SWRN AND CENTRAL MS -- NE OF A WARM
FRONT LYING NW-SE ACROSS E TX/SWRN LA.  THOUGH A WEAK INCREASE IN
AVAILABLE CAPE MAY OCCUR WITH TIME AS THE FRONT EDGES NEWD...SEVERE
RISK SHOULD GRADUALLY DIMINISH WITH THE LA STORMS AS THEY SHIFT NEWD
OVER THE NEXT FEW HOURS.  

FARTHER S/SE HOWEVER...LOW-LEVEL MOISTENING WILL PERSIST AS THE WARM
FRONT JUST S OF THE SERN LA COAST DRIFTS NWD.  WITH WEAK MID-LEVEL
TROUGHING SHIFTING EWD OUT OF TX ENHANCING WEAK QG ASCENT...EXPECT
CONVECTION TO PERSIST.  GIVEN AMPLY VEERING/INCREASING FLOW WITH
HEIGHT ACROSS THE AREA WITHIN THE WARM-ADVECTION REGIME...RISK FOR A
BRIEF TORNADO OR TWO MAY SPREAD ACROSS SERN LA OVER THE NEXT FEW
HOURS.  EVENTUALLY...THIS SLIGHT INCREASE IN RISK MAY EXPAND AS FAR
E AS SRN AL/THE WRN FL PANHANDLE...THOUGH WW IS NOT ANTICIPATED ATTM
ACROSS THIS REGION...WITH THREAT LIKELY TO REMAIN SOMEWHAT SUBDUED.

..GOSS/CORFIDI.. 12/21/2015

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

ATTN...WFO...TAE...MOB...JAN...LIX...LCH...SHV...

LAT...LON   28689120 29269210 30079248 30869304 31729257 32259187
            32369100 32249000 31618903 31318816 31128702 30808545
            29648572 29128665 28708846 28468957 28529090 28689120 

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