297
ACUS02 KWNS 030535
SWODY2
SPC AC 030533
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1233 AM CDT FRI JUL 03 2026
VALID 041200Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SATURDAY AFTERNOON
INTO SATURDAY NIGHT ACROSS PARTS OF THE OHIO VALLEY INTO MID
ATLANTIC AND ACROSS PARTS OF THE CENTRAL GREAT PLAINS...
..SUMMARY
CLUSTERS OF STORMS MAY EVOLVE ACROSS PARTS OF THE ALLEGHENY PLATEAU
INTO MID ATLANTIC AND ACROSS THE CENTRAL GREAT PLAINS SATURDAY
AFTERNOON AND EVENING, POSING A RISK FOR DAMAGING WIND GUSTS. LARGE
HAIL IS ALSO POSSIBLE ACROSS THE GREAT PLAINS
..DISCUSSION
MODELS INDICATE THAT A REMNANT MID-LEVEL HIGH, NOW CENTERED NEAR OR
JUST EAST THE SOUTHERN APPALACHIANS, WILL BECOME SUPPRESSED BY THE
BEGINNING OF THIS PERIOD. A NEW HIGH MAY BECOME A BIT MORE
PROMINENT UPSTREAM, NEAR AND TO THE LEE OF THE SOUTHERN ROCKIES,
WITH RIDGING ALSO BUILDING TO ITS NORTHWEST, FROM PORTIONS OF THE
EASTERN GREAT BASIN THROUGH PORTIONS OF THE MID MISSOURI VALLEY. TO
THE EAST OF THIS RIDGING, WEAK INITIALLY ZONAL FLOW MAY TRANSITION
TO A BROADLY CYCLONIC REGIME ACROSS THE UPPER MIDWEST AND LOWER
MISSOURI INTO OHIO VALLEYS. STRONGER WESTERLIES ARE LIKELY TO
REMAIN CONFINED TO HIGHER LATITUDES, BUT ONE EMBEDDED LARGER-SCALE
TROUGH IS FORECAST TO DIG ACROSS THE CANADIAN MARITIMES AND NEW
ENGLAND SATURDAY THROUGH SATURDAY NIGHT.
IN LOWER LEVELS, MORE SUBSTANTIVE COOLING/DRYING MAY OVERSPREAD MUCH
OF NORTHERN NEW ENGLAND DURING THE DAY, AND PERHAPS THE ADIRONDACKS
VICINITY AND PORTIONS OF THE UPPER GREAT LAKES BY LATE SATURDAY
NIGHT. HOWEVER, THIS MAY BE PRECEDED BY A DIFFUSE/WEAK FRONT,
PERHAPS AUGMENTED BY CONVECTIVE OUTFLOW IS SOME LOCATIONS, ADVANCING
SOUTHWARD ACROSS THE MID ATLANTIC, OHIO AND LOWER MISSOURI VALLEYS
AND CENTRAL GREAT PLAINS THROUGH THE PERIOD.
ALONG AND SOUTH OF THE LEAD FRONT/CONVECTIVE OUTFLOW, A
BOUNDARY-LAYER CHARACTERIZED BY SEASONABLY HIGH MOISTURE CONTENT MAY
AGAIN BECOME CHARACTERIZED BY LARGE POTENTIAL INSTABILITY WITH
DAYTIME HEATING. THIS WILL PROBABLY BECOME SUPPORTIVE OF WIDELY
SCATTERED TO SCATTERED STRONG THUNDERSTORM DEVELOPMENT POSING AT
LEAST SOME SEVERE WEATHER RISK. THE MAGNITUDE/AREAL COVERAGE OF
THIS POTENTIAL REMAINS UNCERTAIN, AND WILL LARGELY BE INFLUENCED BY
SUB-SYNOPTIC DEVELOPMENTS THAT ARE OF LOW PREDICTABILITY AT THIS
EXTENDED TIME FRAME, AS EVIDENCED BY SIZABLE MODEL SPREAD STILL
APPARENT IN LATEST MODEL OUTPUT, INCLUDING CONVECTION-ALLOWING
GUIDANCE.
..ALLEGHENY PLATEAU INTO MID ATLANTIC
POTENTIAL CONVECTIVE EVOLUTION REMAINS UNCERTAIN, WITH FORCING FOR
ASCENT TO SUPPORT THUNDERSTORM DEVELOPMENT UNCLEAR. HOWEVER, THERE
APPEARS SOME GENERAL CONSENSUS IN MODEL OUTPUT THAT AT LEAST
SCATTERED THUNDERSTORM DEVELOPMENT WILL INITIATE IN RESPONSE TO
DAYTIME BOUNDARY-LAYER DESTABILIZATION ACROSS THE ALLEGHENY PLATEAU,
AS MID-LEVEL HEIGHTS SUBTLY BEGIN TO FALL. THIS IS FORECAST TO
DEVELOP EASTWARD ACROSS THE MID ATLANTIC BY EARLY EVENING.
GIVEN THE DEGREE OF INSTABILITY FORECAST, AND POSSIBLY A BELT OF
CONVECTIVELY AUGMENTED FLOW (INCLUDING 30-40 KT IN THE 850-500 MB
LAYER) SPREADING EAST-SOUTHEAST OF THE LOWER GREAT LAKES/UPPER OHIO
VALLEY VICINITY, THERE APPEARS POTENTIAL FOR ONE OR TWO ORGANIZING
CLUSTERS CAPABLE OF PRODUCING DAMAGING WIND GUSTS TO EVOLVE.
..CENTRAL GREAT PLAINS
GIVEN THE POSSIBLE GENERAL TENDENCY FOR LARGER-SCALE MID-LEVEL
HEIGHT RISES ACROSS THE ROCKIES AND ADJACENT GREAT PLAINS, AND
SPREAD EVIDENT IN MODEL OUTPUT, CONVECTIVE POTENTIAL FOR THIS PERIOD
REMAINS UNCERTAIN. HOWEVER, LINGERING CONVECTIVELY GENERATED OR
AUGMENTED PERTURBATIONS WITHIN EVOLVING NORTHWESTERLY MID-LEVEL FLOW
COULD SUPPORT WIDELY SCATTERED STRONG TO SEVERE THUNDERSTORM
DEVELOPMENT, INCLUDING A FEW SUPERCELLS BY EARLY SATURDAY EVENING.
THIS MAY BE FOCUSED IN MOISTENING SOUTHEASTERLY LOW-LEVEL FLOW
ACROSS PARTS OF NORTHEASTERN COLORADO AND WESTERN NEBRASKA, AND NEAR
A ZONE OF STRENGTHENING DIFFERENTIAL HEATING ON THE SOUTHWESTERN
FLANK OF A STALLED OUTFLOW BOUNDARY ACROSS WESTERN INTO CENTRAL
KANSAS.
WARM ADVECTION AND CONVERGENCE NEAR THE NOSE OF A NOCTURNALLY
STRENGTHENING SOUTHERLY LOW-LEVEL JET, WITH BOUNDARY-LAYER
DECOUPLING ACROSS THE OKLAHOMA/TEXAS PANHANDLE VICINITY INTO
SOUTHWESTERN KANSAS, SEEMS TO OFFER THE BEST SUPPORT FOR A POSSIBLE
UPSCALE GROWING CLUSTER, WHICH COULD MAINTAIN A RISK FOR LARGE HAIL
AND STRONG TO SEVERE SURFACE GUSTS INTO SATURDAY NIGHT.
..KERR.. 07/03/2026
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