[BNAWX] Severe Storm Outlook Narrative

[EMWIN Server]

ACUS11 KWNS 110222
SWOMCD
SPC MCD 110221
ALZ000-TNZ000-MSZ000-ARZ000-110345-

MESOSCALE DISCUSSION 0874
NWS STORM PREDICTION CENTER NORMAN OK
0921 PM CDT SAT MAY 10 2008

AREAS AFFECTED...NERN AR...WRN/MIDDLE TN...NRN AL...NRN MS

CONCERNING...TORNADO WATCH 298...300...

VALID 110221Z - 110345Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 298...300...CONTINUES.

LATEST MESOANALYSIS DEPICTS A WARM FRONT EXTENDING SE FROM THE
MID-SOUTH INTO THE TN VLY AT 02Z.  SOUTH OF THE FRONT...THE BOUNDARY
LAYER CONTINUED TO MOISTEN/DESTABILIZE WITH LWR 70S DEW POINTS NOW
OBSERVED AS FAR N AS THE TN/MS BORDER AND INTO NWRN AL.  THIS WAS
CONTRIBUTING TO MLCAPES OF 2000-2500 J/KG.

VWP FROM HIGH TOP AL AND COLUMBUS MS SHOW A STRONGLY SHEARED 0-6KM
LAYER WITH VALUES AOA 60 KTS.  GIVEN MAGNITUDE OF MID-LEVEL LAPSE
RATES/INSTABILITY PRESENT...THERE IS NO SURPRISE AT THE WELL-
MAINTAINED LARGE SUPERCELL TSTMS OVER MIDDLE TN SWWD INTO NWRN MS AT
MID-EVENING.

SUPERCELL STRUCTURES WILL CONTINUE TO BE POSSIBLE THROUGH LATE
EVENING DOWNSTREAM INTO NRN MS...SRN MIDDLE TN AND NRN AL.
BUT...NUMBER OF STORMS DEVELOPING WITHIN THE INCREASING WARM
ADVECTION PROFILE MAY JUMP-START AN EVOLUTION INTO BOW
ECHOES/DERECHO.  THUS...ALONG WITH TORNADO POTENTIAL...DMGG WIND
GUSTS WILL ALSO BE LIKELY...WITH SOME WIND GUSTS IN EXCESS OF 65
KTS.  MAIN ACTIVITY WILL REACH NERN MS/NWRN AL BY 04Z...WITH STORMS
DEVELOPING SEWD INVOF THE WARM FRONT BEFORE THEN.

MEANWHILE...UPSTREAM WITHIN WRN PARTS OF TORNADO WATCH 298...TSTMS
JUST UPSTREAM ACROSS NCNTRL AR APPEAR TO BE WEAKENING AS THEY INGEST
RAIN-COOLED PARCELS FROM THE LEADING STORMS IN THE TN VLY/MID-SOUTH.
 THIS WEAKENING TREND IS EXPECTED TO CONTINUE AS THE LLJ BEGINS TO
VEER INTO NRN MS/MIDDLE TN REGION WITH TIME THIS EVENING.

..RACY.. 05/11/2008

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

ATTN...WFO...OHX...BMX...HUN...MEG...JAN...

35929047 35708781 35378659 34408578 33578607 33308735
33868894 34219015 34829067 35839083

This weather bulletin was brought to you by:
www.nashvilleweather.net