183  
ACUS01 KWNS 111242  
SWODY1  
SPC AC 111241  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0741 AM CDT WED MAR 11 2026  
 
VALID 111300Z - 121200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER  
MISSISSIPPI VALLEY ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE  
MID-ATLANTIC...  
   
..SUMMARY
 
 
ISOLATED TO SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED TODAY FROM  
THE ARKLATEX AND LOWER MISSISSIPPI VALLEY NORTHEASTWARD THROUGH THE  
OHIO VALLEY AND MID-ATLANTIC.  
   
..SYNOPSIS
 
 
SPLIT-FLOW UPPER PATTERN PERSISTS ACROSS THE CONUS THIS MORNING,  
WITH AN UPPER LOW MOVING THROUGH TX IN THE SOUTHERN STREAM AND A  
SHORTWAVE TROUGH MOVING THROUGH THE NORTHERN AND CENTRAL PLAINS  
WITHIN THE NORTHERN STREAM. BOTH OF THESE SYSTEMS ARE FORECAST TO  
PROGRESS QUICKLY EASTWARD AMID MODEST PHASING AND TREND TOWARDS A  
MORE CONFLUENT, SINGLE-STREAM PATTERN BY EARLY TOMORROW MORNING.  
 
CURRENTLY A BROAD REGION OF MODERATE TO STRONG LOW/MID-LEVEL FLOW  
EXTENDS FROM TX NORTHEASTWARD INTO EASTERN ONTARIO/SOUTHERN QUEBEC.  
THE STRONGEST LOW-LEVEL FLOW WITH THIS BROAD REGION IS OVER THE  
LOWER/MIDDLE OHIO VALLEY, WHERE 850 MB FLOW IS AROUND 50 TO 60 KT.  
THUNDERSTORMS ARE CURRENTLY CLUSTERED OVER TWO AREAS WITHIN THIS  
BROADER REGION, IL AND OH, AND FARTHER SOUTH FROM EAST TX INTO THE  
ARKLATEX. THE GREATEST SEVERE THUNDERSTORM POTENTIAL IS EXPECTED TO  
CONCENTRATE DOWNSTREAM OF THE AREAS TODAY, WITH DAMAGING GUSTS AS  
THE PRIMARY SEVERE HAZARDS.  
   
..OHIO VALLEY THROUGH THE MID-ATLANTIC
 
 
REGIONAL RADAR IMAGERY SHOWS A CONVECTIVE LINE EXTENDING FROM  
WEST-CENTRAL IN SOUTHWESTWARD INTO SOUTHERN IL. THIS LINE IS  
PROGRESSING QUICKLY EAST-NORTHEASTWARD AND HAS PRODUCED SEVERAL  
STRONG GUSTS (I.E. 40-45 KT) THUS FAR. REGIONAL RADAR IMAGERY ALSO  
DEPICTS A MCV MOVING INTO SOUTHERN IL. MESOSCALE ASCENT ATTENDANT TO  
THIS MCV COULD BE AIDING IN THE DEVELOPMENT OF THE CONVECTIVE LINE  
AS WELL AS THE MORE CELLULAR STORMS TO ITS SOUTH. GENERAL  
EXPECTATION IS FOR THIS CONVECTIVE LINE TO CONTINUE QUICKLY  
NORTHEASTWARD ACROSS THE OHIO VALLEY, WITH THE ROBUST LOW-LEVEL FLOW  
SUPPORT IN THE POTENTIAL STRONG TO SEVERE GUSTS AS WELL AS A FEW  
LINE-EMBEDDED TORNADOES. THIS ACTIVITY WILL SPREAD EAST TOWARD THE  
MIDDLE ATLANTIC BY LATE AFTERNOON.  
 
THIS ONGOING LINE IS WELL AHEAD OF A SHORTWAVE TROUGH MOVING THROUGH  
THE NORTHERN/CENTRAL PLAINS, AND STRONG LOW-LEVEL MOISTURE ADVECTION  
WILL LIKELY RESULT IN AIRMASS RECOVERY IN ITS WAKE AHEAD OF THE  
SHORTWAVE. AS A RESULT, A SECOND ROUND OF THUNDERSTORMS IS  
ANTICIPATED AS THE SHORTWAVE AND ITS ASSOCIATED COLD FRONT MOVES  
THROUGH THE OHIO VALLEY DURING THE AFTERNOON AND EVENING. DESPITE  
AIRMASS RECOVERY, THE OVERALL BUOYANCY WILL LIKELY BE TEMPERED BY  
WIDESPREAD CLOUDS AND MUTED DIURNAL HEATING. EVEN SO, THE  
COMBINATION OF MODEST BUOYANCY WITH ROBUST SHEAR WILL STILL SUPPORT  
ANOTHER ROUND OF STRONG TO SEVERE THUNDERSTORMS. STRONG GUSTS ARE  
THE PRIMARY RISK, BUT LINE-EMBEDDED TORNADOES ARE POSSIBLE AS WELL.  
ANY MATURE DISCRETE DEVELOPMENT AHEAD OF THE FRONT WOULD LIKELY BE  
SUPERCELLULAR AND CAPABLE OF ALL SEVERE HAZARDS, INCLUDING  
TORNADOES.  
   
..EAST TEXAS THROUGH THE SOUTHEAST
 
 
A FEW STRONG TO SEVERE THUNDERSTORMS ARE CURRENTLY ONGOING WITHIN A  
BROAD AREA OF PRECIPITATION FROM EAST TX INTO SOUTHERN AR, SUPPORTED  
BY MODEST BUOYANCY AND STRONG VERTICAL SHEAR DOWNSTREAM OF A  
SHORTWAVE MOVING THROUGH WEST TX. AS MENTIONED IN RECENTLY ISSUED  
MCD 211, SOME WEAKENING AND VEERING OF LOW-LEVEL FLOW HAS BEEN NOTED  
IN REGIONAL VWPS, BUT DEEP-LAYER SHEAR REMAINS FAVORABLE, AND  
SEASONABLY RICH LOW-LEVEL MOISTURE WILL CONTINUE TO SUPPORT MODERATE  
BUOYANCY. THE SEVERE THREAT MAY TEND TO REMAIN RATHER ISOLATED IN  
THE SHORT TERM, THOUGH THE STRONGEST CELLS/CLUSTERS WILL BE CAPABLE  
OF PRODUCING LOCALLY DAMAGING WIND AND PERHAPS A TORNADO.  
 
A MORE SUBSTANTIAL INCREASE IN THE COVERAGE OF THE SEVERE THREAT IS  
EXPECTED LATER THIS AFTERNOON, IN RESPONSE TO INCREASED ASCENT  
ATTENDANT TO THE APPROACHING SHORTWAVE TROUGH. THIS ADDITIONAL  
DEVELOPMENT WILL LIKELY BEGIN IN A MORE CELLULAR MODE OVER EAST TX  
BEFORE PROGRESSING EASTWARD AND BECOMING MORE LINEAR WITH TIME. ALL  
HAZARDS ARE POSSIBLE WITH THIS MORE CELLULAR ACTIVITY, INCLUDING  
TORNADOES. SOUTHWESTERLY FLOW ALOFT SHOULD STRENGTHEN AHEAD OF THE  
SHORTWAVE THROUGHOUT THE EVENING AND OVERNIGHT, LEADING TO INCREASED  
ORGANIZATION AND STRENGTH OF THE CONVECTIVE LINE. AS SUCH, THE  
THREAT FOR DAMAGING GUSTS AND LINE-EMBEDDED TORNADOES WILL PERSIST  
THROUGHOUT THE NIGHT ACROSS THE GULF COAST STATES.  
 
..MOSIER/DEAN.. 03/11/2026  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SPC Page Main Text Page