312  
ACUS48 KWNS 290900  
SWOD48  
SPC AC 290858  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0358 AM CDT WED APR 29 2026  
 
VALID 021200Z - 071200Z  
   
..DISCUSSION  
 
LATEST MEDIUM-RANGE GUIDANCE, IN PARTICULAR THE ECENS AND GEFS,  
GENERALLY MAINTAINS FORECAST TRENDS OF PRIOR RUNS CONCERNING THE  
EVOLUTION OF THE LARGE-SCALE FEATURES WITHIN THE PREVAILING SPLIT  
FLOW THROUGH THIS WEEKEND INTO EARLY NEXT WEEK. IT APPEARS THAT AT  
LEAST A TRANSIENT BLOCKING HIGH MAY EVOLVE WITHIN AMPLIFIED RIDGING  
OFFSHORE OF THE BRITISH COLUMBIA AND ADJACENT PACIFIC NORTHWEST  
COAST. TO ITS SOUTH-SOUTHEAST A NOTABLE MID-LEVEL LOW IS FORECAST  
TO EVOLVE WITHIN INITIAL TROUGHING SLOWLY DIGGING TOWARD THE U.S.  
PACIFIC COAST, WITH THE LOW BOTTOMING OUT OFFSHORE OF THE CENTRAL/  
SOUTHERN CALIFORNIA COAST BY EARLY NEXT WEEK.  
 
DOWNSTREAM, IT APPEARS THAT A BROAD AREA OF LOWER MID-LEVEL HEIGHTS  
WILL BE MAINTAINED, WITH LOWEST HEIGHTS PERHAPS REFORMING  
WEST-NORTHWESTWARD FROM SOUTHWESTERN QUEBEC TOWARD SOUTHERN HUDSON  
BAY/NORTHWESTERN ONTARIO, CONTRIBUTING TO THE MAINTENANCE OF A  
CONFLUENT REGIME ACROSS AND EAST OF THE ROCKIES.  
 
SHORTER WAVELENGTH DEVELOPMENTS WITHIN THIS PATTERN REMAIN MORE  
UNCERTAIN, PARTICULARLY BY THE EARLY TO MIDDLE PORTION OF NEXT WEEK,  
WHEN IT APPEARS THAT THE OFFSHORE LOW WILL BEGIN TO PROGRESS INLAND  
ACROSS CALIFORNIA AND THE SOUTHERN SIERRA NEVADA. DEPENDING ON THE  
TIMING OF THE INLAND PROGRESSING MID-LEVEL COLD CORE WITH RESPECT TO  
DIURNAL HEATING, THIS COULD BE ACCOMPANIED BY RELATIVELY MINOR  
SEVERE WEATHER POTENTIAL ACROSS PARTS OF THE SAN JOAQUIN VALLEY NEXT  
MONDAY OR TUESDAY.  
 
DOWNSTREAM, SOUTHERLY MOIST RETURN FLOW INTO AT LEAST THE SOUTHERN  
THROUGH CENTRAL GREAT PLAINS, ASSOCIATED WITH DEEPENING LEE SURFACE  
TROUGHING, MAY CONTRIBUTE TO DESTABILIZATION BENEATH BUILDING  
MID-LEVEL RIDGING ACROSS AND EAST OF THE SOUTHERN ROCKIES. THIS  
MIGHT BE ACCOMPANIED BY INCREASING POTENTIAL FOR AT LEAST WIDELY  
SCATTERED STRONG TO SEVERE THUNDERSTORM DEVELOPMENT ON TUESDAY.  
 
GUIDANCE SUGGESTS POTENTIAL FOR MORE WIDESPREAD ORGANIZED SEVERE  
THUNDERSTORM DEVELOPMENT COULD INCREASE BY WEDNESDAY, BUT MUCH WILL  
DEPEND ON SHORT WAVE DEVELOPMENTS WHICH BECOME RATHER UNCERTAIN BY  
THIS TIME.  
 
..KERR.. 04/29/2026  
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