311  
ACUS48 KWNS 100828  
SWOD48  
SPC AC 100826  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0326 AM CDT WED JUN 10 2026  
 
VALID 131200Z - 181200Z  
   
..DISCUSSION  
   
..DAY 4/SATURDAY  
 
THE MODELS ARE IN GENERALLY GOOD AGREEMENT IN DEPICTING A PROMINENT,  
MID/UPPER-LEVEL LOW OVER ONTARIO WITH A SECONDARY, WEAKER LOW OR  
SHORT-WAVE TROUGH ACROSS THE NORTHERN ROCKIES. A BELT OF ENHANCED,  
WESTERLY WINDS IN THE MID LEVELS WILL RESIDE TO THE SOUTH OF THOSE  
FEATURES FROM THE NORTHERN PLAINS THROUGH THE GREAT LAKES. AT THE  
SURFACE, AN AREA OF LOW PRESSURE IS FORECAST ACROSS THE CENTRAL  
PLAINS WITH AN ASSOCIATED FRONT EXTENDING NORTHEAST INTO THE UPPER  
GREAT LAKES.  
 
A STRONGLY UNSTABLE AIR MASS IS FORECAST AHEAD OF THE FRONT ACROSS  
PORTIONS OF THE MID/LOWER MO VALLEY INTO OZARK PLATEAU WITH  
INSTABILITY DECREASING WITH NORTHEASTWARD EXTENT INTO THE UPPER  
GREAT LAKES. THE MODELS INDICATE SUFFICIENTLY STRONG DEEP-LAYER  
SHEAR ACROSS THE FRONTAL ZONE TO SUPPORT ORGANIZED STORM MODES,  
INCLUDING SUPERCELLS. HIGHEST CONFIDENCE IN GREATER STORM COVERAGE  
AND AN ASSOCIATED SEVERE-WEATHER THREAT REMAINS CENTERED ON THE  
MID/LOWER MO VALLEYS. SEVERE-WEATHER PROBABILITIES MAY NEED TO BE  
EXTENDED INTO THE UPPER GREAT LAKES IN SUBSEQUENT OUTLOOKS.  
 
   
..DAY 5/SUNDAY  
 
A NUMBER OF THE DETERMINISTIC MODELS INDICATE A SHORT-WAVE TROUGH  
AND ASSOCIATED JET STREAK MOVING THROUGH THE GREAT LAKES INTO  
NORTHEAST, WITHIN THE BASE OF THE ONTARIO UPPER LOW. FARTHER WEST,  
THE NORTHERN ROCKIES SHORT-WAVE TROUGH WILL ADVANCE TOWARD THE  
CENTRAL ROCKIES. AT THE SURFACE, A COLD FRONT ASSOCIATED WITH THE  
FORMER DISTURBANCE MENTIONED ABOVE WILL PROGRESS THROUGH THE  
NORTHEAST AND OH VALLEY, WITH THE WESTERN EXTENSION OF THE BOUNDARY  
STALLING ACROSS THE SOUTHERN PLAINS.  
 
THE MODELS INDICATE A NARROW AXIS OF MODEST INSTABILITY DEVELOPING  
BY AFTERNOON AHEAD OF THE FRONT FROM THE NORTHERN NEW ENGLAND TO THE  
UPPER OH VALLEY, WHERE THE STRONGEST VERTICAL SHEAR IS FORECAST.  
SOME SEVERE WEATHER APPEARS POSSIBLE IN THOSE AREAS; HOWEVER, THE  
LIMITED EXTENT OF THE WARM SECTOR LEADS TO UNCERTAINTY IN THE  
COVERAGE AND DURATION OF ANY THREAT.  
 
GREATER INSTABILITY AND A WIDER WARM SECTOR ARE FORECAST WITH  
SOUTHWESTWARD EXTENT FROM THE OH RIVER AND TN VALLEY INTO SOUTHERN  
PLAINS. GENERALLY WEAK VERTICAL SHEAR IS FORECAST ACROSS THE FRONTAL  
ZONE, WHICH SHOULD LIMIT THE DEGREE OF STORM ORGANIZATION. A  
POSSIBLE EXCEPTION IS ACROSS THE SOUTHERN AND CENTRAL HIGH PLAINS,  
WHERE AN EASTERLY LOW-LEVEL WIND COMPONENT WILL BOOST DEEP-LAYER  
SHEAR TO SOME EXTENT. MODEL TRENDS WILL BE MONITORED FOR THE  
POSSIBLE INCLUSION OF SEVERE-WEATHER PROBABILITIES IN THAT AREA.  
 
   
..DAY 6/MONDAY  
 
THE DETERMINISTIC MODELS ARE IN REASONABLY GOOD AGREEMENT IN  
AMPLIFYING THE AFOREMENTIONED SHORT-WAVE TROUGH OVER THE CENTRAL  
PLAINS WITH AN ASSOCIATED BELT OF ENHANCED MID-LEVEL FLOW EXTENDING  
THROUGH THE OH VALLEY INTO NORTHEAST. AT THE SURFACE, THERE IS SOME  
SIGNAL THAT AN AREA OF LOW PRESSURE COULD DEVELOP ALONG A FRONT  
ACROSS THE SOUTHERN PLAINS INTO OZARK PLATEAU. SOME SEVERE-WEATHER  
THREAT APPEARS POSSIBLE IN THAT AREA, AS WELL AS ALONG THE FRONT  
THAT IS EXPECTED TO STRETCH EAST THROUGH THE TN VALLEY INTO THE  
CAROLINAS. PREDICTABILITY IN THE SPECIFIC DETAILS ARE TOO LOW TO  
INCLUDE AN AREA.  
 
   
..DAYS 7-8/TUESDAY AND WEDNESDAY  
 
THE ENSEMBLE MEAN SOLUTIONS ARE IN RELATIVELY GOOD AGREEMENT IN  
SUGGESTING THE CENTRAL PLAINS SHORT-WAVE TROUGH WILL BECOME ABSORBED  
INTO BROADER-SCALE TROUGH AMPLIFICATION EAST OF THE MS VALLEY. AT  
THE SURFACE, IT APPEARS THAT A FRONTAL WAVE WILL MOVE FROM THE TN  
VALLEY TOWARD THE MID-ATLANTIC COAST, WHILE A TRAILING COLD FRONT  
ADVANCES INTO THE GULF COAST STATES. WHILE AREAS OF SEVERE WEATHER  
ARE POSSIBLE DURING THIS TIME FRAME, PREDICTABILITY IN THEIR  
LOCATION IS LOW.  
 
..MEAD.. 06/10/2026  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page