794
ACUS02 KWNS 280602
SWODY2
SPC AC 280600
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CDT SUN JUN 28 2026
VALID 291200Z - 301200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WITHIN PORTIONS OF
THE NORTHERN AND CENTRAL PLAINS INTO THE UPPER MIDWEST...
..SUMMARY
SEVERE THUNDERSTORMS ARE POSSIBLE FROM PARTS OF THE CENTRAL/NORTHERN
PLAINS INTO THE UPPER MIDWEST ON MONDAY. LARGE HAIL AND SEVERE WINDS
ARE THE PRIMARY CONCERNS, THOUGH A COUPLE OF TORNADOES MAY ALSO
OCCUR.
..SYNOPSIS
A COMPACT SHORTWAVE TROUGH WILL EVOLVE OUT OF THE UPPER TROUGH IN
THE NORTHERN ROCKIES. THE TIMING OF THIS FEATURE REMAINS A BIT
UNCERTAIN. THE STRONGEST MID-LEVEL ASCENT WILL LIKELY OCCUR IN
EASTERN DAKOTAS/WESTERN MINNESOTA AFTER 00Z. A SURFACE LOW WILL
DEEPEN WITHIN THE EASTERN DAKOTAS AND LIFT NORTH-NORTHEAST WITH
TIME. A VERY MOIST AIRMASS WILL BE IN PLACE BETWEEN A COLD FRONT IN
THE CENTRAL PLAINS AND A WARM FRONT IN THE UPPER MIDWEST. UPPER
LEVEL RIDGING WILL CONTINUE IN THE MIDWEST/EAST WITH MODEST
BREAKDOWN OF THIS RIDGE EXPECTED IN THE DAKOTAS/MINNESOTA.
..EASTERN DAKOTAS INTO NORTHERN MINNESOTA
THE FORECAST REMAINS RATHER UNCERTAIN ACROSS THESE REGIONS. AT LEAST
WEAK CONVECTION APPEARS PROBABLE WITHIN PARTS OF THE DAKOTAS INTO
WESTERN MINNESOTA DURING THE MORNING. HOW THIS ACTIVITY EVOLVES WILL
PLAY A ROLE IN WHERE AFTERNOON SEVERE POTENTIAL WILL EXIST. MODEL
AGREEMENT HAS MARGINALLY INCREASED WITH REGARD TO THE EVOLUTION OF
THE SHORTWAVE TROUGH IN THE NORTHERN PLAINS AND THE SURFACE LOW
MIGRATING NORTH-NORTHEAST NEAR THE RED RIVER. EVEN SO, UPPER-LEVEL
RIDGING THAT WILL PERSIST THROUGH MUCH OF THE PERIOD LIMITS
CONFIDENCE IN IF AND HOW MANY STORMS WILL DEVELOP DURING THE
AFTERNOON/EARLY EVENING. SHOULD SUFFICIENT DESTABILIZATION OCCUR
NEAR THE SURFACE LOW, A PORTION OF EASTERN NORTH DAKOTA INTO
NORTHWEST MINNESOTA APPEAR TO HAVE THE GREATEST RELATIVE POTENTIAL
FOR SEVERE STORMS. ALL SEVERE HAZARDS WOULD BE POSSIBLE GIVEN THE
50+ KT OF EFFECTIVE SHEAR, 4000+ J/KG MLCAPE, AND LOCALLY STRONGER
LOW-LEVEL SHEAR. MODEL SOLUTIONS FOR ACTIVITY NEAR THE SURFACE LOW
AND AREAS SOUTHWARD INTO EASTERN SOUTH DAKOTA AND WESTERN MINNESOTA
ARE HIGHLY DISPARATE. THE ECMWF WOULD SUGGEST SOME POTENTIAL FOR AN
MCS TO DEVELOP NEAR THE SURFACE LOW AND TRACK THROUGH PARTS OF
NORTHERN/EAST-CENTRAL MINNESOTA ALONG THE BUOYANCY GRADIENT. THIS
PARTICULAR SCENARIO HAS BEEN FAIRLY CONSISTENT ALONG WITH THE
DEPICTION OF A MORE SOUTHERN SURFACE LOW/UPPER TROUGH. SOLUTIONS
SUCH AS THE RRFS WOULD SUGGEST A SUPERCELL OR TWO COULD OCCUR
FARTHER SOUTH ALONG THE SOUTH DAKOTA/MINNESOTA BORDER.
..NEBRASKA INTO SOUTHERN/CENTRAL MINNESOTA
THOUGH THE TIMING OF DEVELOPMENT DIFFERS, THERE HAS BEEN AN
INCREASING CONVECTIVE SIGNAL TREND IN RECENT GUIDANCE ALONG THE COLD
FRONT. THERE IS AT LEAST SOME POTENTIAL FOR THIS TO OCCUR DURING
LATE AFTERNOON WITH A WINDOW FOR STORMS TO BE SURFACE BASED, BUT IT
IS MORE PROBABLE THAT IT OCCURS AFTER DARK WHEN THE LOW-LEVEL JET
INCREASES. LARGE HAIL COULD OCCUR EARLY IN THE CONVECTIVE CYCLE, BUT
DEEP-LAYER SHEAR PARALLEL TO THE BOUNDARY SHOULD MEAN A QUICK
TRANSITION INTO LINEAR STRUCTURES. SEVERE WIND GUSTS WILL LIKELY BE
THE PRIMARY CONCERN, THOUGH A LOW-END TORNADO THREAT MAY EXIST GIVEN
THE STRONGER LOW-LEVEL JET.
..WENDT.. 06/28/2026
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