702  
ACUS01 KWNS 140559  
SWODY1  
SPC AC 140557  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1257 AM CDT FRI AUG 14 2026  
 
VALID 141200Z - 151200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE MID MISSOURI AND MID MISSISSIPPI VALLEYS...  
   
..SUMMARY  
 
THUNDERSTORMS WITH SEVERE WIND GUSTS AND HAIL WILL BE POSSIBLE THIS  
AFTERNOON AND EVENING ACROSS PARTS OF THE MID MISSOURI AND MID  
MISSISSIPPI VALLEYS. ISOLATED SEVERE GUSTS WILL ALSO BE POSSIBLE IN  
PARTS OF THE CENTRAL PLAINS AND FROM THE OHIO VALLEY TO THE  
MID-ATLANTIC.  
   
..MID MISSOURI AND MID MISSISSIPPI VALLEYS  
 
A BROAD ANTICYCLONIC FLOW PATTERN WILL BE IN PLACE OVER MUCH OF THE  
CENTRAL U.S. TODAY, AS A SUBTLE EMBEDDED SHORTWAVE TROUGH MOVES  
THROUGH THE MID MISSOURI VALLEY. AHEAD OF THIS FEATURE, A  
QUASI-STATIONARY FRONT WILL BE IN PLACE FROM SOUTHERN IOWA  
EAST-SOUTHEASTWARD INTO NORTH-CENTRAL ILLINOIS. THIS BOUNDARY WILL  
BE THE FOCUS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON. SURFACE  
DEWPOINTS ALONG THE BOUNDARY WILL BE IN THE 70S F, WHICH WILL RESULT  
IN STRONG DESTABILIZATION BY AFTERNOON. SURFACE-BASED CONVECTIVE  
INITIATION IS EXPECTED ALONG THE INSTABILITY GRADIENT DURING THE  
LATE AFTERNOON TO THE SOUTH OF OMAHA. FROM THESE INITIAL STORMS, A  
LINE IS EXPECTED TO ORGANIZE AND MOVE EASTWARD ACROSS SOUTH-CENTRAL  
IOWA AND FAR NORTHERN MISSOURI DURING THE LATE AFTERNOON AND EARLY  
EVENING.  
 
RAP FORECAST SOUNDINGS AHEAD OF THE LINE AT 00Z FROM DES MOINES  
SOUTHWARD INTO FAR NORTHERN MISSOURI HAVE MLCAPE IN THE 2000 TO 3500  
J/KG RANGE. SOME DIRECTIONAL SHEAR IS PRESENT IN THE LOW-LEVELS, AND  
0-6 KM SHEAR IS IN THE 30 TO 35 KNOT RANGE. THIS ENVIRONMENT WILL BE  
FAVORABLE FOR BOWING LINE SEGMENTS CAPABLE OF SEVERE WIND GUSTS. AN  
EMBEDDED SUPERCELL WITH A HAIL THREAT WILL ALSO BE POSSIBLE. THE  
SEVERE THREAT IS EXPECTED TO MOVE EASTWARD INTO NORTHWEST AND  
NORTH-CENTRAL ILLINOIS DURING THE EVENING.  
   
..CENTRAL PLAINS  
 
SOUTHWESTERLY MID-LEVEL FLOW WILL BE IN PLACE TODAY OVER MUCH OF THE  
WESTERN AND CENTRAL U.S. A SUBTLE SHORTWAVE TROUGH WILL MOVE  
NORTHEASTWARD INTO THE CENTRAL HIGH PLAINS. LARGE-SCALE ASCENT  
ASSOCIATED WITH THE TROUGH AND TOPOGRAPHIC LIFT IN THE FOOTHILLS OF  
THE ROCKIES WILL BE FAVORABLE FOR SCATTERED CONVECTIVE INITIATION BY  
EARLY AFTERNOON. THUNDERSTORMS WILL MOVE NORTHEASTWARD INTO THE  
CENTRAL HIGH PLAINS AND INTO A MODERATELY UNSTABLE AIRMASS. SOME RAP  
FORECAST SOUNDINGS IN EAST-CENTRAL COLORADO DURING THE LATE  
AFTERNOON HAVE 0-6 KM SHEAR AROUND 25 KNOTS WITH LOW TO MID-LEVEL  
LAPSE RATES EXCEEDING 7 C/KM. THIS WILL LIKELY SUPPORT ISOLATED  
SEVERE WIND GUSTS AND HAIL.  
   
..OHIO VALLEY/CENTRAL APPALACHIANS/MID-ATLANTIC  
 
WEST-NORTHWESTERLY MID-LEVEL FLOW WILL BE IN PLACE TODAY OVER MUCH  
OF THE NORTHEASTERN U.S. AT THE SURFACE, AN AXIS OF MODERATE  
INSTABILITY WILL DEVELOP BY AFTERNOON FROM THE OHIO VALLEY  
EAST-SOUTHEASTWARD INTO THE MID-ATLANTIC. ALONG AND NEAR THE  
INSTABILITY AXIS, LOW-LEVEL CONVERGENCE WILL BE THE PRIMARY FOCUS  
FOR CONVECTIVE INITIATION. NEAR AND DOWNSTREAM OF THESE POCKETS OF  
CONVERGENCE, ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO  
DEVELOP. THE MODERATE INSTABILITY WITH PRECIPITABLE WATER VALUES IN  
THE 2 TO 2.2 INCH RANGE SHOULD SUPPORT A THREAT FOR ISOLATED SEVERE  
WET DOWNBURSTS.  
 
..BROYLES/LYONS.. 08/14/2026  
 
 
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