644  
ACUS01 KWNS 280101  
SWODY1  
SPC AC 280100  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0800 PM CDT MON JUL 27 2026  
 
VALID 280100Z - 281200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE OHIO VALLEY...  
   
..SUMMARY
 
 
THUNDERSTORMS WITH SEVERE WIND GUSTS AND HAIL ARE EXPECTED THIS  
EVENING ACROSS PARTS OF THE OHIO VALLEY. ADDITIONAL STORMS WITH  
SEVERE WIND GUSTS ARE ALSO EXPECTED FROM LOWER MICHIGAN SOUTHWARD  
INTO OHIO. A FEW STRONG GUSTS WILL ALSO BE POSSIBLE IN PARTS OF THE  
CENTRAL PLAINS AND IN SOUTH-CENTRAL ARIZONA.  
   
..OHIO VALLEY/GREAT LAKES
 
 
ON WATER VAPOR IMAGERY, A MID-LEVEL SHORTWAVE TROUGH IS MOVING  
SOUTHWARD THROUGH THE OHIO VALLEY. AHEAD OF THIS FEATURE, A MOIST  
AND UNSTABLE AIRMASS IS IN PLACE WITH SURFACE DEWPOINTS IN THE 70S  
AND LOW 80S F. THE RAP HAS A POCKET OF STRONG INSTABILITY LOCATED  
FROM WESTERN KENTUCKY INTO SOUTHERN INDIANA, WHERE MLCAPE IS  
ESTIMATED IN THE 3500 TO 4500 J/KG RANGE. SCATTERED STRONG TO SEVERE  
STORMS ARE ONGOING ALONG THE NORTHERN EDGE OF THE STRONGER  
INSTABILITY, AND THE STORMS ARE BEING SUPPORTED BY LARGE-SCALE  
ASCENT ASSOCIATED WITH THE SHORTWAVE TROUGH. IN ADDITION, THE  
WSR-88D VWP AT LOUISVILLE HAS 0-6 KM SHEAR OF 30 TO 35 KNOTS  
SUGGESTING A POTENTIAL FOR ORGANIZED SEVERE STORMS WILL CONTINUE  
THIS EVENING. SEVERE WIND GUSTS WILL BE POSSIBLE WITH SUPERCELLS AND  
SHORT BOWING LINE SEGMENTS. THE GREATEST COVERAGE OF SEVERE IS  
EXPECTED TO BE OVER SOUTHERN INDIANA AND FAR NORTHERN KENTUCKY...SEE  
MCD 1774.  
 
FURTHER NORTH INTO LOWER MICHIGAN, SCATTERED STRONG THUNDERSTORMS  
ARE ONGOING AHEAD A SUBTLE SHORTWAVE TROUGH EVIDENT ON WATER VAPOR  
IMAGERY. SHORT-TERM MODEL FORECASTS SUGGEST THESE STORMS WILL EXPAND  
IN COVERAGE AND MOVE SOUTHWARD ACROSS LOWER MICHIGAN INTO OHIO  
DURING THE LATE EVENING AND EARLY OVERNIGHT PERIOD. ALONG THIS  
CORRIDOR, THE RAP HAS MLCAPE IN THE 1000 TO 1500 J/KG RANGE WITH 40  
TO 50 KNOT OF DEEP-LAYER SHEAR. THIS SHOULD SUPPORT A WIND-DAMAGE  
THREAT WITH ORGANIZED SHORT LINE SEGMENTS.  
   
..CENTRAL PLAINS
 
 
AT MID-LEVELS, A SUBTLE SHORTWAVE TROUGH IS CURRENTLY MOVING OVER  
THE TOP OF A RIDGE IN THE CENTRAL HIGH PLAINS. AHEAD OF THE  
SHORTWAVE TROUGH, SCATTERED STRONG THUNDERSTORMS ARE ONGOING ALONG  
THE WESTERN EDGE OF A POCKET OF STRONG INSTABILITY. THE RAP  
CURRENTLY SHOWS MLCAPE OVER CENTRAL NEBRASKA IN THE 4000 TO 5500  
RANGE. EVEN THOUGH FORECAST SOUNDINGS NEAR THE INSTABILITY MAXIMUM  
HAVE LOW TO MID-LEVEL WIND SPEEDS GENERALLY LESS THAN 20 KNOTS, THE  
INSTABILITY COMBINED WITH VERY STEEP LOW-LEVEL LAPSE RATES MAY BE  
ENOUGH FOR ISOLATED SEVERE WIND GUSTS FOR A FEW MORE HOURS THIS  
EVENING.  
   
..ARIZONA
 
 
THE LATEST SURFACE ANALYSIS SHOWS A SUFFICIENTLY MOIST AIRMASS IN  
PLACE OVER THE SOUTHERN HALF OF ARIZONA, WHERE DEWPOINTS ARE MOSTLY  
IN THE MID TO UPPER 50S F. WITHIN THE MOIST AIR, THE RAP HAS A  
POCKET OF MODERATE INSTABILITY WITH MLCAPE IN THE 1500 TO 2500 J/KG  
RANGE. THUNDERSTORM HAVE DEVELOPED ALONG THE NORTHERN EDGE OF THE  
STRONGER INSTABILITY. THESE STORMS WILL MOVE WESTWARD ACROSS  
SOUTH-CENTRAL ARIZONA THIS EVENING, AND MAY POSE A THREAT FOR SEVERE  
WIND GUSTS DUE TO VERY STEEP LOW TO MID-LEVEL LAPSE RATES...MCD  
1772.  
 
..BROYLES.. 07/28/2026  
 

 
 
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