909  
ACUS11 KWNS 212034  
SWOMCD  
SPC MCD 212033  
LAZ000-MSZ000-212230-  
 
MESOSCALE DISCUSSION 2071  
NWS STORM PREDICTION CENTER NORMAN OK  
0333 PM CDT FRI AUG 21 2026  
 
AREAS AFFECTED...LOWER MISSISSIPPI RIVER VALLEY  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 609...  
 
VALID 212033Z - 212230Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 609  
CONTINUES.  
 
SUMMARY...THE POTENTIAL FOR DAMAGING WINDS WILL CONTINUE THROUGH  
LATE AFTERNOON ACROSS THE LOWER MISSISSIPPI RIVER VALLEY.  
 
DISCUSSION...REGIONAL RADAR IMAGERY OUT OF SOUTHERN MS AND EASTERN  
LA DEPICTS POORLY ORGANIZED, AND LARGELY OUTFLOW-DOMINANT,  
CONVECTION. THESE CELLS/CLUSTERS HAVE BEEN PRODUCING OCCASIONALLY  
STRONG DOWNBURSTS WITH VELOCITY DATA DEPICTING 40-50 KNOT OUTFLOW  
WITHIN THE LOWEST 1-2 KFT ARL. ADDITIONALLY, SURFACE STATIONS THAT  
HAVE BEEN IMPACTED BY OUTFLOW HAVE REPORTED TEMPERATURE REDUCTIONS  
ON THE ORDER OF 20 F. GIVEN THESE CONDITIONS WITHIN THE CONVECTIVE  
COLD POOLS AND WEAK LOW-LEVEL SHEAR SAMPLED BY REGIONAL VWPS,  
OUTFLOW BOUNDARIES SHOULD BECOME MORE PROMINENT WITHIN THE NEXT HOUR  
OR SO. BOUNDARY COLLISIONS DOWNSTREAM ACROSS EAST/SOUTHEAST LA WILL  
LIKELY PROMOTE ADDITIONAL UPDRAFT DEVELOPMENT WITHIN A HOT AND  
UNSTABLE AIR MASS (CHARACTERIZED BY LOW-LEVEL LAPSE RATES  
APPROACHING 9 C/KM AND MLCAPE ESTIMATED TO BE AROUND 2500-3000  
J/KG). INTENSE DOWNBURSTS WILL BE POSSIBLE WITH THE MORE VIGOROUS  
UPDRAFT PULSES AS ADDITIONAL CONVECTION DEVELOPS AND SPREADS SOUTH  
INTO THIS AIR MASS OVER THE NEXT FEW HOURS. GIVEN THE THERMODYNAMIC  
CONDITIONS, EMBEDDED SWATHS OF 45-60 MPH APPEAR POSSIBLE WITHIN THE  
STRONGEST DOWNBURSTS.  
 
..MOORE.. 08/21/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...JAN...LIX...LCH...SHV...  
 
LAT...LON 30859220 31719195 32069162 32249124 32259096 32169064  
31869029 31359017 30909009 30529019 30369031 30189054  
30109085 30119122 30159150 30269183 30499206 30859220  
 
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH  
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