838  
ACUS01 KWNS 161645  
SWODY1  
SPC AC 161644  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1144 AM CDT SUN AUG 16 2026  
 
VALID 161630Z - 171200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE FRONT  
RANGE AND CENTRAL/NORTHERN HIGH PLAINS AND OHIO  
VALLEY/MID-ATLANTIC...  
   
..SUMMARY
 
 
THUNDERSTORMS WITH DAMAGING WIND GUSTS WILL BE POSSIBLE THIS  
AFTERNOON AND EARLY EVENING OVER PARTS OF THE OHIO VALLEY AND  
MID-ATLANTIC. LARGE HAIL AND ISOLATED SEVERE WIND GUSTS WILL ALSO BE  
POSSIBLE ACROSS THE FRONT RANGE AND CENTRAL/NORTHERN HIGH PLAINS.  
   
..UPPER OHIO VALLEY TO APPALACHIANS AND MID-ATLANTIC/CAROLINAS
 
 
AN MCV PERSISTS AT MIDDAY ACROSS FAR SOUTHEAST MICHIGAN AND NORTHERN  
OHIO, WITH SOME RECENT UPTICK IN CONVECTION AHEAD OF IT ACROSS  
NORTHERN OHIO. REFERENCE MESOSCALE DISCUSSION 1195 FOR SHORT-TERM  
DETAILS REGARDING A FURTHER INCREASE IN SEVERE POTENTIAL THROUGH  
EARLY/MID-AFTERNOON WITHIN THIS REGIONAL CORRIDOR.  
 
WHILE STORMS HAVE WEAKENED, SHOWERS/CLOUD COVER REMAIN PREVALENT  
NEAR/EAST OF THE APPALACHIANS AT MIDDAY ACROSS THE MID-ATLANTIC  
REGION. THIS WILL TEND TO LIMIT/DELAY DESTABILIZATION IN MANY AREAS  
(ESPECIALLY WITH NORTH-NORTHEASTWARD EXTENT). THAT SAID, AIR MASS  
RECOVERY/ADVECTION IS EXPECTED FROM THE WEST, WITH AMPLE UPSTREAM  
CLEARING PER VISIBLE SATELLITE IMAGERY ACROSS THE CUMBERLAND PLATEAU  
INTO PARTS OF THE ALLEGHENY PLATEAU. PENDING THE TIMING/LOCATION OF  
DESTABILIZATION, SOME TERRAIN/LEE TROUGH-RELATED DEVELOPMENT MAY  
DIURNALLY OCCUR, ALTHOUGH THE MOST PREVALENT/MORE CERTAIN SCENARIO  
MAY BE FOR POTENTIALLY SEVERE STORMS TO SPREAD INTO THE REGION THIS  
EVENING. DAMAGING WINDS WILL BE THE MOST COMMON HAZARD REGIONALLY,  
ALTHOUGH A TORNADO COULD OCCUR, ATTRIBUTABLE TO MCV-ENHANCED FLOW  
AND/OR WITH ANY STORMS INTERACTING WITH THE EFFECTIVE WARM FRONT  
ACROSS THE MID-ATLANTIC REGION.  
   
..MIDDLE MISSISSIPPI VALLEY INCLUDING MISSOURI/ILLINOIS
 
 
AN MCV OVER THE NEBRASKA/KANSAS/IOWA/MISSOURI BORDER VICINITY LATE  
THIS MORNING WILL LIKELY CONTINUE GENERALLY EASTWARD, WHILE PROBABLY  
LARGELY MAINTAINING ITS RELATED BELT OF ENHANCED MID-LEVEL FLOW AS  
OBSERVED FROM REGIONAL WSR-88D VWP DATA. A KEY DOWNSTREAM  
UNCERTAINTY IS THE MIDDAY PERSISTENCE OF WEAK CONVECTION ACROSS  
EASTERN MISSOURI INTO WEST/SOUTHWEST ILLINOIS, AND THAT MID-LEVEL  
LAPSE RATES ARE RATHER POOR TO ITS NORTH ASIDE FROM SOME LINGERING  
CLOUD COVER.  
 
MORE CERTAIN/GREATER DESTABILIZATION MAY OCCUR TO THE WEST ACROSS  
MISSOURI, WITH THE SOUTHEASTWARD-ADVANCING FRONT BEING A FOCUS FOR  
RENEWED THUNDERSTORM DEVELOPMENT LATER THIS AFTERNOON AND EVENING  
AMIDST MODERATE/LOCALLY STRONG BUOYANCY. DEEP-LAYER SHEAR WILL TEND  
TO BE LIMITED TO AROUND 30 KT IN MOST AREAS, ALTHOUGH SOMEWHAT  
STRONGER MCV-RELATED WINDS ALOFT MAY SUPPORT UPWARDS OF 35-40 KT  
EFFECTIVE SHEAR FOR ANY STORMS ACROSS NORTHERN MISSOURI INTO  
WEST-CENTRAL/SOUTHWEST ILLINOIS. BOUTS OF DAMAGING WINDS ARE THE  
MOST LIKELY HAZARD REGIONALLY.  
   
..FRONT RANGE/RATON MESA AND NORTHERN/CENTRAL HIGH PLAINS
 
 
A RELATIVELY SIMILAR PATTERN/SCENARIO AS PRIOR FEW DAYS WILL  
CONTINUE REGIONALLY, EXCEPT A SOMEWHAT MORE NORTHWARD-EXTENT OF THE  
SEVERE RISK (SUCH AS BLACK HILLS VICINITY) AND A TREND TOWARD A MORE  
NORTHERLY COMPONENT TO THE FLOW ALOFT ACROSS THE NORTH-CENTRAL HIGH  
PLAINS. AT LEAST WIDELY SCATTERED THUNDERSTORM DEVELOPMENT IS  
EXPECTED INTO MID/LATE AFTERNOON SPANNING THE FRONT RANGE/RATON MESA  
VICINITY NORTHWARD ACROSS EASTERN WYOMING/SOUTHEAST MONTANA AND THE  
BLACK HILLS VICINITY. IN THE PRESENCE OF UPWARDS OF 1500-2000 J/KG  
MLCAPE, MODERATE VERTICAL SHEAR (30-40 KT) COULD SUPPORT A FEW  
SUPERCELLS CAPABLE OF SEVERE HAIL. ISOLATED DAMAGING WINDS WILL BE  
POSSIBLE. THIS INCLUDES THE MOST PROBABLE ZONE FOR GRADUAL  
UPSCALE-GROWING LINEAR CLUSTER(S) ACROSS THE SOUTH-CENTRAL HIGH  
PLAINS/RATON MESA VICINITY INCLUDING SOUTHEAST COLORADO/NORTHEAST  
NEW MEXICO TOWARD THE OKLAHOMA/TEXAS PANHANDLES AND FAR SOUTHWEST  
KANSAS. A COUPLE OF SOUTHEASTWARD-MOVING THUNDERSTORM CLUSTERS  
CAPABLE OF WIND/DAMAGE MAY ALSO EMERGE THIS EVENING OUT OF THE BLACK  
HILLS VICINITY/WESTERN NEBRASKA.  
 
..GUYER/CHALMERS.. 08/16/2026  
 

 
 
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