Severe Weather May 9th 2021

[weatherextreme]

[janetjanet998]

13Z 

 

DAY 1 CONVECTIVE OUTLOOK    
NWS STORM PREDICTION CENTER NORMAN OK  
0757 AM CDT SUN MAY 09 2021  
  
VALID 091300Z - 101200Z  
  
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS EAST  
TEXAS/ARKLAMISS AND MID-SOUTH...  
   
..SUMMARY  
  
SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED FROM PARTS OF  
CENTRAL/EAST TEXAS INTO THE LOWER MISSISSIPPI VALLEY AND MID-SOUTH.  
LARGE HAIL, DAMAGING WIND GUSTS, AND A COUPLE OF TORNADOES ALL  
APPEAR POSSIBLE. OTHER MORE ISOLATED STRONG/SEVERE STORMS MAY OCCUR  
ACROSS THE SOUTHERN HIGH PLAINS.  
   
..CENTRAL/EAST TEXAS TO MID-SOUTH/MIDDLE TENNESSEE  
  
AHEAD OF A SOUTHEASTWARD-MOVING COLD FRONT, THE REMNANTS OF AN MCS  
CONTINUE TO PERSIST WITH SOUTH-SOUTHEASTWARD OUTFLOW ADVANCEMENT  
ACROSS THE OZARKS EARLY THIS MORNING. WITH THE GREATER RESERVOIR OF  
LOW-LEVEL MOISTURE/INSTABILITY TO THE SOUTHWEST OF THIS REMNANT MCS,  
SOME QUESTIONS EXIST REGARDING THE MAGNITUDE OF THE SEVERE RISK  
PARTICULARLY WITH NORTHEASTWARD EXTENT LATER TODAY, ESPECIALLY TO  
THE N/NE OF WESTERN TENNESSEE.   
  
A BELT OF RELATIVELY STRONG/LOW-AMPLITUDE WESTERLIES WILL INFLUENCE  
THE REGION, WITH A VERY STRONG LOW-LEVEL JET EARLY TODAY EXPECTED TO  
DIURNALLY WEAKEN BUT STILL REMAIN RELATIVELY STRONG FROM THE  
ARKLAMISS INTO THE TENNESSEE VALLEY WITHIN THE PREFRONTAL  
ENVIRONMENT. ON THE SOUTHERN FRINGES OF EARLY DAY MCS-RESIDUAL  
OUTFLOW/CLOUD COVER, CLOUD BREAKS WILL CONTRIBUTE TO  
MODERATE/LOCALLY STRONG DESTABILIZATION FROM CENTRAL AND  
EAST/NORTHEAST TEXAS INTO SOUTHERN/EASTERN ARKANSAS AND PORTIONS OF  
WESTERN TENNESSEE/NORTHERN MISSISSIPPI. INCREASING SURFACE-BASED  
DEEP CONVECTIVE DEVELOPMENT IS ANTICIPATED NEAR THE  
SOUTHEASTWARD-ADVANCING COLD FRONT AS WELL AS IN VICINITY OF REMNANT  
OUTFLOW/ZONES OF DIFFERENTIAL HEATING ACROSS THE MID-SOUTH.  
  
FORECAST SOUNDINGS SUGGEST INITIAL SUPERCELLS ARE LIKELY AHEAD OF  
THE FRONT AS SURFACE-6KM BULK SHEAR WILL BE ON THE ORDER OF 40 KT  
WHERE MLCAPE VALUES ARE LIKELY TO EXCEED 2000 J/KG. LOCAL HAIL  
ALGORITHMS SUGGEST 2+ INCH STONES ARE POSSIBLE WITH THE STRONGEST  
STORMS, WHICH WILL BE MOST PROBABLE WITHIN THE FIRST COUPLE OF HOURS  
OF CONVECTIVE DEVELOPMENT. A COUPLE OF TORNADOES COULD ALSO OCCUR  
ALONG WITH A MORE PREVALENT DAMAGING WIND POTENTIAL BY EARLY  
EVENING.  

[Chinook]

Convection-allowing models generally agree that there will be an organized line of thunderstorms in central and east Texas, possibly using CAPE values of 3000-4000 J/kg.