316
ACUS02 KWNS 121730
SWODY2
SPC AC 121728
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1228 PM CDT FRI JUN 12 2026
VALID 131200Z - 141200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SATURDAY
AFTERNOON INTO SATURDAY NIGHT ACROSS EASTERN KANSAS...ADJACENT
PORTIONS OF SOUTHEASTERN NEBRASKA AND NORTHEASTERN OKLAHOMA...AND
MUCH OF WESTERN THROUGH CENTRAL MISSOURI...
..SUMMARY
ONE OR TWO EVOLVING THUNDERSTORM CLUSTERS APPEAR POSSIBLE ACROSS
PARTS OF THE CENTRAL GREAT PLAINS AND LOWER MISSOURI VALLEY VICINITY
SATURDAY AFTERNOON THROUGH SATURDAY NIGHT. SOME OF THIS ACTIVITY
WILL POSE A RISK FOR PRODUCING LARGE HAIL AND SWATHS OF STRONG,
POTENTIALLY DAMAGING WIND GUSTS.
..DISCUSSION
DOWNSTREAM OF AMPLIFIED MID-LEVEL RIDGING, OFFSHORE OF THE U.S.
PACIFIC COAST THROUGH BRITISH COLUMBIA, IT APPEARS THAT FLOW WILL
BEGIN TO VEER TO AN INCREASING NORTHWESTERLY COMPONENT ACROSS AND
EAST OF THE ROCKIES THROUGH THIS PERIOD. WITHIN THIS REGIME,
SUBSTANTIVE MID-LEVEL TROUGHING IS FORECAST TO DIG ACROSS THE UPPER
MIDWEST, TO THE SOUTHWEST OF A LINGERING MID-LEVEL LOW CENTERED
ACROSS NORTHWESTERN ONTARIO. SPREAD WITHIN MODEL OUTPUT REMAINS
LARGER CONCERNING SHORT WAVE PERTURBATIONS DIGGING THROUGH INITIALLY
WEAKER FLOW ACROSS THE MISSOURI THROUGH LOWER OHIO VALLEYS, AND THE
EXTENT TO WHICH THEY MAY BEGIN TO SUPPRESS THE NORTHERN PERIPHERY OF
SUBTROPICAL RIDGING CENTERED OVER THE NORTHERN GULF BASIN.
IN LOWER LEVELS, AN INITIAL, CONVECTIVE OUTFLOW ENHANCED, SURFACE
FRONT OVERSPREADING MUCH OF THE MID ATLANTIC THROUGH MID SOUTH
VICINITY WILL LIKELY ALREADY BE IN THE PROCESS OF WEAKENING AT THE
OUTSET OF THE PERIOD. HOWEVER, SURGES OF COOLER/DRIER AIR WILL
CONTINUE TO DEVELOP SOUTHWARD INTO AND THROUGH THE INTERIOR OF THE
U.S., WITH THE GENERAL LEADING EDGE REACHING THE LOWER GREAT LAKES
THROUGH OHIO VALLEY, OZARKS PLATEAU AND TEXAS SOUTH PLAINS BY 12Z
SUNDAY. THIS MAY BE PRECEDED ACROSS THE OHIO VALLEY THROUGH WESTERN
SLOPES OF THE APPALACHIANS BY OUTFLOW FROM EXTENSIVE PRIOR
CONVECTIVE DEVELOPMENT.
..CENTRAL GREAT PLAINS INTO MISSOURI VALLEY
THE POTENTIAL FOR INCREASING THUNDERSTORM DEVELOPMENT AT THE OUTSET
OF THE PERIOD ACROSS EASTERN NEBRASKA INTO WESTERN IOWA (NEAR THE
NOSE OF AN EAST-NORTHEASTWARD ADVECTING PLUME OF ELEVATED
MIXED-LAYER AIR) COUPLED WITH POTENTIAL FOR SUBSTANTIVE, BUT
WEAKENING, REMNANT CONVECTION FROM OVERNIGHT OVERSPREADING THE OZARK
PLATEAU, CONTRIBUTE TO CONTINUING UNCERTAINTY CONCERNING SUBSEQUENT
CONVECTIVE DEVELOPMENT SATURDAY THROUGH SATURDAY NIGHT.
THE EVOLUTION OF CONVECTIVE OUTFLOWS, AND THEIR IMPACT ON
BOUNDARY-LAYER DESTABILIZATION, COUPLED WITH UNCERTAIN SHORT WAVE
DEVELOPMENTS, WILL SUBSTANTIALLY IMPACT THE TIMING, LOCATION AND
POTENTIAL UPSCALE GROWTH OF POTENTIALLY STRONGER THUNDERSTORM
DEVELOPMENT.
HOWEVER, BENEATH THE PLUME OF ELEVATED MIXED-LAYER AIR, A CORRIDOR
OF STRONGER BOUNDARY-LAYER HEATING AND DEEPER MIXING ACROSS KANSAS
DURING THE DAY SEEMS TO PROVIDE THE HIGHEST CERTAINTY FOR MODERATE
TO STRONG DESTABILIZATION. NEAR THE NOSE OF THIS REGIME, SOMEWHERE
ACROSS EASTERN KANSAS INTO WESTERN MISSOURI, BASED ON A CONSENSUS OF
MODEL OUTPUT, LOW-LEVEL WARM ADVECTION IN THE PRESENCE OF WEAKER
INHIBITION MAY PROVIDE THE FOCUS FOR INTENSIFYING THUNDERSTORM
DEVELOPMENT BY LATE AFTERNOON. AND THERE APPEARS A GENERAL SIGNAL
IN THE MODEL OUTPUT THAT A MODIFYING OUTFLOW BOUNDARY/ZONE OF
DIFFERENTIAL HEATING MAY PROVIDE A FOCUS FOR THE SOUTHEASTWARD
DEVELOPMENT OF UPSCALE GROWING CONVECTION TOWARD THE MID SOUTH
THROUGH SATURDAY NIGHT. AS THIS OCCURS, INCREASING THUNDERSTORM
DEVELOPMENT ALSO APPEARS PROBABLE AHEAD OF THE SOUTHWARD ADVANCING
COLD FRONT ACROSS KANSAS THROUGH OKLAHOMA AND THE TEXAS PANHANDLE
VICINITY.
ALTHOUGH DEEP-LAYER SHEAR MAY BE INITIALLY MODEST, IT MAY STILL BE
SUFFICIENT TO SUPPORT THE EVOLUTION OF A FEW SUPERCELLS CAPABLE OF
PRODUCING LARGE HAIL AND POTENTIAL FOR A COUPLE TORNADOES, BEFORE
EVOLVING SWATHS OF STRONG TO SEVERE WIND GUSTS BECOME THE MORE
PROMINENT THREAT WITH ORGANIZING CLUSTERS INTO LATE SATURDAY
EVENING.
..KERR.. 06/12/2026
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