594  
ACUS02 KWNS 141722  
SWODY2  
SPC AC 141720  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1220 PM CDT THU MAY 14 2026  
 
VALID 151200Z - 161200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF  
THE LOWER MISSOURI RIVER VALLEY...  
   
..SUMMARY  
 
SEVERE STORMS WITH LARGE TO VERY LARGE HAIL AND SEVERE WIND GUSTS  
WILL BE POSSIBLE FRIDAY AFTERNOON AND EVENING IN PARTS OF THE  
CENTRAL PLAINS AND LOWER TO MID MISSOURI VALLEY.  
   
..SYNOPSIS  
 
A PREDOMINANTLY ZONAL FLOW REGIME ALOFT WILL PERSIST OVER THE  
CENTRAL U.S. THROUGH FRIDAY. AN EMBEDDED WEAK UPPER-LEVEL  
DISTURBANCE (CURRENTLY OVER THE SOUTHWEST) WILL MIGRATE EASTWARD  
ACROSS THE CENTRAL PLAINS THROUGH TOMORROW, REACHING THE MID-MS  
RIVER VALLEY BY LATE EVENING. THIS FLOW REGIME WILL PROMOTE MODEST  
DEEPENING OF A SURFACE LOW OVER WESTERN OK/KS THROUGH THE DAY WITH  
CONTINUED NORTHWARD ADVECTION OF A SEASONALLY MOIST AIR MASS TO THE  
EAST OF A DRYLINE AND AHEAD OF AN INVERTED SURFACE TROUGH ACROSS THE  
PLAINS/UPPER MIDWEST. THUNDERSTORM DEVELOPMENT IS ANTICIPATED ALONG  
THESE BOUNDARIES BY LATE AFTERNOON, LIKELY LASTING INTO THE  
OVERNIGHT HOURS FOR PORTIONS OF THE LOWER MISSOURI RIVER  
VALLEY/MIDWEST.  
   
..LOWER MISSOURI RIVER VALLEY  
 
THUNDERSTORM INITIATION IS ANTICIPATED BY LATE AFTERNOON ACROSS  
CENTRAL NE ALONG THE INVERTED SURFACE TROUGH WHERE WARM CONDITIONS  
ON THE FRINGE OF RETURNING MOISTURE SHOULD YIELD WEAKLY CAPPED  
THERMODYNAMIC PROFILES. STRONGER MID-LEVEL FLOW ACROSS THE CENTRAL  
PLAINS WILL FAVOR HIGHER PROBABILITIES FOR ORGANIZED CONVECTION,  
INCLUDING THE POTENTIAL FOR SUPERCELLS. HOWEVER, WEAK LOW-LEVEL  
STORM-RELATIVE WINDS WITHIN A DEEPLY MIXED AIR MASS MAY PROMOTE  
OUTFLOW-DOMINANT CONVECTION AND THE POTENTIAL FOR RELATIVELY QUICK  
UPSCALE GROWTH. WHILE DISCRETE MODES CAN BE MAINTAINED, STEEP  
MID-LEVEL LAPSE RATES AND STRONG ZONAL SPEED SHEAR WILL PROMOTE THE  
POTENTIAL FOR LARGE/VERY LARGE HAIL.  
 
REGARDLESS, OVER THE PAST 12-24 HOURS BOTH DETERMINISTIC AND  
ENSEMBLE GUIDANCE HAVE TRENDED TOWARDS A MORE NORTH/NORTHWESTERLY  
PLACEMENT OF THE INVERTED TROUGH AS WELL AS THE ZONE OF CONVECTIVE  
INITIATION AND DOWNSTREAM STORM PROPAGATION. BASED ON THESE TRENDS,  
15% HAIL AND WIND PROBABILITIES HAVE BEEN SHIFTED NORTHWARD.  
ADDITIONALLY, 5% HAIL/WIND PROBABILITIES WERE EXPANDED EASTWARD INTO  
PORTIONS OF THE MIDWEST WHERE STRONG DEEP-LAYER WIND SHEAR AND  
ELEVATED BUOYANCY MAY MAINTAIN CONVECTIVE INTENSITY THROUGH THE  
OVERNIGHT HOURS.  
   
..SOUTHERN PLAINS  
 
PERSISTENT WEST/SOUTHWESTERLY MID-LEVEL FLOW WILL FAVOR STEEP (8-9  
C/KM) LAPSE RATE ADVECTION EASTWARD OVER THE SOUTHERN PLAINS THROUGH  
THE NEXT 48 HOURS. DESPITE DRY CONDITIONS TO THE WEST OF THE  
DRYLINE, STRONG DIURNAL HEATING COUPLED WITH STEEP LAPSE RATES  
SHOULD YIELD DEEPLY-MIXED, AND NEARLY UNINHIBITED, PROFILES BY LATE  
AFTERNOON. ALTHOUGH BUOYANCY VALUES WILL BE MODEST, HIGH-BASED  
CONVECTION OVER A VERY DEEPLY MIXED BOUNDARY LAYER MAY SUPPORT  
STRONG TO SEVERE DOWNBURST WINDS. RECENT HREF/REFS SOLUTIONS HINT  
THAT SEVERE WINDS ASSOCIATED WITH HIGH-BASED CONVECTION MAY DEVELOP  
AS FAR WEST AS WEST AS THE OK/TX PANHANDLES, THOUGH CONSIDERABLE  
SPREAD IS NOTED AMONG DETERMINISTIC SOLUTIONS. HOWEVER, A WESTWARD  
EXPANSION OF THE 5% WIND/MARGINAL CONTOUR WAS MADE TO ACCOUNT FOR  
THIS POTENTIAL.  
 
TO THE EAST OF THE DRYLINE, STRONG CAPPING AT THE BASE OF THE EML  
WILL LIKELY LIMIT STORM COVERAGE. HOWEVER, A FEW RECENT CAM  
SOLUTIONS HINT THAT ASCENT ALONG THE DRYLINE MAY BE SUFFICIENT FOR  
ISOLATED CONVECTION BY LATE AFTERNOON/EARLY EVENING. 30 KNOT  
MID-LEVEL FLOW OVER THE WARM SECTOR WILL SUPPORT ORGANIZATION OF ANY  
DEEP CONVECTION THAT CAN BECOME SUSTAINED, INCLUDING THE POTENTIAL  
FOR A SUPERCELL OR TWO CAPABLE OF LARGE HAIL.  
 
..MOORE.. 05/14/2026  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page