514  
ACUS01 KWNS 231957  
SWODY1  
SPC AC 231956  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0256 PM CDT TUE APR 23 2024  
 
VALID 232000Z - 241200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTHWEST  
TEXAS...  
   
..SUMMARY
 
 
ISOLATED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL  
(POTENTIALLY 2+ INCH DIAMETER) AND GUSTS TO 65 MPH WILL BE POSSIBLE  
THIS AFTERNOON AND EVENING ACROSS NORTHWEST TEXAS.  
   
..20Z UPDATE
 
 
OVERALL FORECAST OUTLINED IN THE PREVIOUS DISCUSSION (APPENDED  
BELOW) REMAINS VALID. AS MENTIONED IN RECENTLY ISSUED MCD 506, A  
SUPERCELL OR TWO SHOULD DEVELOP ACROSS A PORTION OF WESTERN NORTH  
TEXAS THROUGH LATE AFTERNOON, WITH LARGE HAIL OF 1.5 TO 2.5 INCHES  
IN DIAMETER AND LOCALIZED SEVERE GUSTS OF 60-70 MPH POSSIBLE. AN  
ISOLATED STORM OR TWO IS ALSO POSSIBLE FARTHER SOUTH IN THE TEXAS  
TRANS PECOS VICINITY. MARGINALLY SEVERE HAIL (I.E. AROUND 1" IN  
DIAMETER) AND DAMAGING GUSTS ARE POSSIBLE HERE AS WELL.  
 
FARTHER NORTH, ISOLATED THUNDERSTORMS ARE STILL ANTICIPATED FROM  
NORTHERN IL INTO LOWER MI AHEAD OF AN APPROACHING SHORTWAVE TROUGH  
AND ASSOCIATED COLD FRONT. A FEW STRONG TO SEVERE STORMS ARE  
POSSIBLE WITH SMALL TO MARGINALLY SEVERE HAIL AND DAMAGING WINDS AS  
THE PRIMARY HAZARDS (AS MENTIONED IN RECENTLY ISSUED MCD 507).  
 
...EARLY TOMORROW MORNING FROM TX PANHANDLE INTO  
NORTH-CENTRAL/CENTRAL OK...  
ELEVATED THUNDERSTORMS MAY DEVELOP FROM THE NORTHEAST TX/EASTERN OK  
PANHANDLES INTO CENTRAL/NORTH-CENTRAL OK WITHIN THE WARM-AIR  
ADVECTION REGIME ALONG THE NORTHEASTERN EDGE OF THE RETURNING  
LOW-LEVEL MOISTURE. STEEP MID-LEVEL LAPSE RATES AND FAVORABLE  
CLOUD-BEARING LAYER SHEAR COULD SUPPORT AN ISOLATED INSTANCE OR TWO  
OF HAIL WITH INITIAL DEVELOPMENT. HOWEVER, SEVERE COVERAGE IS  
CURRENTLY EXPECTED TO REMAIN LESS THAN 5%, PRECLUDING THE  
INTRODUCTION OF ANY OUTLOOK AREAS.  
 
..MOSIER.. 04/23/2024  
   
PREV DISCUSSION
 
/ISSUED 1123 AM CDT TUE APR 23 2024/  
   
..NORTHWEST TX
 
 
VISIBLE SATELLITE IMAGERY AND SURFACE ANALYSIS THIS MORNING INDICATE  
THE INITIAL STAGE OF MOISTURE RETURN IS OCCURRING ACROSS THE  
SOUTHERN GREAT PLAINS IN THE WAKE OF A FRONTAL INTRUSION INTO THE  
GULF A FEW DAYS AGO. A MID-LEVEL RIDGE WILL INCREASINGLY BECOME  
ESTABLISHED ACROSS THE CENTRAL/SOUTHERN ROCKIES AND ADJACENT HIGH  
PLAINS AS A GREAT LAKES DISTURBANCE GRADUALLY BECOMES MORE DISPLACED  
FROM THE REGION. AN ASSOCIATED COLD FRONT WILL MOVE SOUTHWARD  
ACROSS KS/OK BEFORE EVENTUALLY STALLING TONIGHT ACROSS SOUTHEAST OK  
AND NORTHWEST TX. WEAK LEE CYCLOGENESIS WILL AID IN MAINTAINING A  
SOUTHERLY LOW-LEVEL FETCH ACROSS CENTRAL INTO WEST TX AS STRONG  
HEATING RESULTS IN A SHARPENING DRYLINE BY LATE AFTERNOON. ISOLATED  
THUNDERSTORM DEVELOPMENT WILL BE MOST PROBABLE NEAR THE TRIPLE POINT  
20-22Z. STEEP LAPSE RATES COUPLED WITH ADEQUATE MOISTURE (1500-2000  
J/KG MLCAPE) AND VEERING FLOW BENEATH MODERATE WESTERLIES, WILL  
SUPPORT AN INITIAL SUPERCELL MODE. ISOLATED VERY LARGE HAIL OF  
2-2.5 INCHES IN DIAMETER WILL BE THE MAIN THREAT, ALONG WITH A FEW  
55-65 MPH GUSTS.  
   
..NORTHERN IL/SOUTHEAST WI/LOWER MI LATE THIS AFTERNOON/EVENING
 
 
HAVE NOT CHANGED THE EXISTING OUTLOOK FOR THIS REGION DUE PRIMARILY  
TO CONSISTENCY IN MODEL DATA AND THE FORECAST CONCEPTUAL MODEL NOT  
DEVIATING. WATER-VAPOR IMAGERY THIS MORNING SHOWS A MID-LEVEL  
TROUGH OVER THE UPPER MIDWEST AND THIS WILL CONTINUE SOUTHEAST INTO  
THE CENTRAL GREAT LAKES BY MID EVENING. AN ASSOCIATED SURFACE  
TROUGH WILL LIKEWISE MOVE SOUTHEASTWARD, AND THIS TROUGH WILL BE  
PRECEDED BY A BAND OF RAIN WITH MINIMAL BUOYANCY. BEHIND THE RAIN  
BAND, SURFACE HEATING WITH STEEPENING LOW-LEVEL LAPSE RATES AND  
COOLING MIDLEVEL TEMPERATURES WILL SUPPORT WEAK SURFACE-BASED  
BUOYANCY JUST AHEAD OF A SECONDARY FRONTAL SURGE. SOME LOW-TOPPED  
CONVECTION WILL BE POSSIBLE LATE THIS AFTERNOON THROUGH LATE EVENING  
FROM NORTHERN IL/SOUTHEAST WI INTO LOWER MI. THE STRONGER STORMS  
COULD YIELD A LOCALIZED MARGINAL HAIL/DAMAGING WIND THREAT.  
 

 
 
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