541  
ACUS01 KWNS 290547  
SWODY1  
SPC AC 290546  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1246 AM CDT SAT MAR 29 2025  
 
VALID 291200Z - 301200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO  
THE OVERNIGHT HOURS ACROSS NORTHERN OKLAHOMA AND SOUTHEASTERN KANSAS  
INTO WESTERN MISSOURI...  
   
..SUMMARY
 
 
WIDELY SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PARTS OF  
THE CENTRAL AND SOUTHERN GREAT PLAINS INTO MIDDLE MISSISSIPPI VALLEY  
TODAY THROUGH TONIGHT. THIS MAY INCLUDE AN ORGANIZING CLUSTER OF  
STORMS ACROSS PARTS OF NORTHERN OKLAHOMA AND SOUTHEASTERN KANSAS  
THROUGH WESTERN MISSOURI THIS EVENING INTO THE OVERNIGHT HOURS.  
   
..DISCUSSION
 
 
DOWNSTREAM OF A BLOCKED REGIME, INCLUDING AN INCREASINGLY PROMINENT  
MID-LEVEL HIGH CENTERED OVER THE WESTERN ALEUTIANS, MODELS INDICATE  
THAT A BROAD, DEEP MID-LEVEL LOW WILL CONTINUE TO EVOLVE ACROSS THE  
NORTHEASTERN PACIFIC. TO THE SOUTH OF THIS FEATURE, MID-LEVEL FLOW  
IS FORECAST TO INTENSIFY IN A WESTERLY BELT ACROSS THE SOUTHERN  
MID-LATITUDES, TOWARD THE CENTRAL AND SOUTHERN CALIFORNIA COAST.  
THIS WILL BE PRECEDED INLAND BY A NUMBER OF WEAKER PERTURBATIONS  
ACROSS THE SOUTHERN GREAT BASIN AND ROCKIES, THROUGH THE GREAT  
PLAINS, WHERE AT LEAST A COUPLE MAY GRADUALLY BEGIN TO CONSOLIDATE  
INTO LARGER-SCALE TROUGHING BY 12Z SUNDAY.  
 
A SUB-1000 MB LOW HAS ALREADY FORMED WITHIN SURFACE TROUGHING TO THE  
LEE OF THE COLORADO ROCKIES. HOWEVER, MODELS INDICATE LITTLE, IF  
ANY, FURTHER DEEPENING THROUGH THIS PERIOD. THE IMPACT OF  
SEASONABLY COLD AIR, NOW NOSING SOUTHWARD TO THE LEE OF THE NORTHERN  
ROCKIES, REMAINS UNCLEAR. BUT GUIDANCE GENERALLY INDICATES THAT THE  
PRIMARY LOW WILL EITHER MIGRATE ACROSS OR REFORM EAST-NORTHEAST OF  
THE CENTRAL GREAT PLAINS INTO IOWA BY LATE TONIGHT, WITH THE  
TRAILING COLD FRONT SURGING ACROSS THE CENTRAL GREAT PLAINS.  
 
IT APPEARS THAT THIS WILL BE PRECEDED BY A MOISTENING SOUTHERLY  
RETURN FLOW, WHICH PROBABLY WILL INCLUDE SURFACE DEW POINTS RISING  
THROUGH THE 60S ACROSS MUCH OF THE LOWER SOUTHERN INTO CENTRAL GREAT  
PLAINS BY EARLY THIS EVENING, AND INTO PORTIONS OF THE UPPER MIDWEST  
BY EARLY SUNDAY. MODELS INDICATE THAT THIS WILL OCCUR BENEATH A  
NARROW PLUME OF ELEVATED MIXED-LAYER AIR SLOWLY SPREADING ACROSS AND  
EAST OF THE GREAT PLAINS INTO MISSISSIPPI VALLEY.  
   
..SOUTHERN GREAT PLAINS TOWARD THE UPPER MIDWEST
 
 
BY LATE THIS AFTERNOON, THE LOW-LEVEL MOISTURE RETURN, COUPLED WITH  
INSOLATION BENEATH THE ELEVATED MIXED-LAYER, MAY CONTRIBUTE TO CAPE  
IN EXCESS OF 1000 J/KG AS THE LEADING EDGE OF MID-LEVEL COOLING  
OVERSPREADS PORTIONS OF THE CENTRAL GREAT PLAINS INTO MID/LOWER  
MISSOURI VALLEY VICINITY. THIS IS FORECAST TO ACCOMPANY AN INITIAL  
SHORT WAVE PERTURBATION, THOUGH THE STRONGER MID/UPPER FORCING FOR  
ASCENT MAY REMAIN LARGELY FOCUSED ABOVE COLD SURFACE-BASED AIR TO  
THE NORTHWEST AND NORTH OF THE SURFACE LOW. STILL, THE INITIATION  
OF ISOLATED TO WIDELY SCATTERED THUNDERSTORM DEVELOPMENT ALONG THE  
DRYLINE MAY NOT BE ENTIRELY OUT OF THE QUESTION, PARTICULARLY ACROSS  
NORTH CENTRAL KANSAS, BEFORE PROPAGATING EAST-NORTHEASTWARD WITHIN  
AN ENVIRONMENT CONDUCIVE FOR SUPERCELL DEVELOPMENT.  
 
THERE HAS BEEN A MORE CONSISTENT SIGNAL EVIDENT IN MODEL OUTPUT  
CONCERNING THUNDERSTORM INITIATION WITH FORCING ACCOMPANYING A  
TRAILING PERTURBATION LIKELY TO IMPACT THE VICINITY OF THE COLD  
FRONT AND DRYLINE INTERSECTION BY EARLY THIS EVENING. IT APPEARS  
THAT THIS WILL PROBABLY BE FOCUSED ACROSS NORTHWESTERN OKLAHOMA,  
PERHAPS AS FAR NORTH AS THE INTERSTATE 35 CORRIDOR OF SOUTH CENTRAL  
KANSAS AND AS FAR SOUTH AS NORTHWESTERN PORTIONS OF THE GREATER  
OKLAHOMA CITY AREA, BEFORE SPREADING EAST-NORTHEASTWARD TOWARD THE  
LOWER MISSOURI VALLEY/OZARK PLATEAU THROUGH EARLY SUNDAY.  
 
THIS MAY COINCIDE WITH BETTER BOUNDARY-LAYER MOISTURE RETURN  
(INCLUDE SURFACE DEW POINTS INCREASING INTO THE MID 60S F+, WHICH  
MAY CONTRIBUTE TO CAPE IN EXCESS OF 2000 J/KG) AND STRENGTHENING  
LOW-LEVEL AND DEEP-LAYER SHEAR, WHICH IS LIKELY TO BECOME SUPPORTIVE  
OF A FEW SUPERCELLS, AT LEAST INITIALLY. ACTIVITY MAY GRADUALLY  
GROW UPSCALE INTO AN ORGANIZING CLUSTER, ACCOMPANIED BY POTENTIAL  
FOR LARGE HAIL, DAMAGING WIND GUSTS, AND PERHAPS A TORNADO OR TWO.  
 
FARTHER SOUTH, THE RISK FOR SEVERE WEATHER APPEARS TO REMAIN LARGELY  
CONDITIONAL. HREF GUIDANCE AND OTHER MODEL OUTPUT SUGGEST ONLY LOW  
PROBABILITY FOR THUNDERSTORM INITIATION OVERNIGHT, ROUGHLY ACROSS  
PARTS OF THE EDWARDS PLATEAU INTO CENTRAL TEXAS, WHERE MODERATE  
POTENTIAL BOUNDARY-LAYER INSTABILITY MAY REMAIN CAPPED BY WARM, DRY  
AIR IN THE LOWER/MID-TROPOSPHERE.  
 
..KERR/WEINMAN.. 03/29/2025  
 

 
 
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