832
ACUS02 KWNS 111731
SWODY2
SPC AC 111729
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1229 PM CDT MON MAY 11 2026
VALID 121200Z - 131200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST
KANSAS AND EXTREME NORTHERN OKLAHOMA NORTHEAST INTO SOUTHERN
WISCONSIN AND WESTERN INDIANA AS WELL AS ACROSS EASTERN FLORIDA
PENINSULA...
..SUMMARY
ISOLATED SEVERE STORMS WITH STRONG WIND GUSTS AND HAIL WILL BE
POSSIBLE ON TUESDAY FROM PARTS OF SOUTHEAST KANSAS AND FAR
NORTHEASTERN OKLAHOMA NORTHEASTWARD INTO NORTHERN ILLINOIS,
NORTHWEST INDIANA AND FAR SOUTHEAST WISCONSIN. ADDITIONAL STORMS
CAPABLE OF DAMAGING WINDS WILL BE POSSIBLE ACROSS THE EASTERN
FLORIDA PENINSULA.
.. OVERVIEW
THE MIDLEVEL PATTERN WILL FURTHER AMPLIFY ON TUESDAY WITH A
NEGATIVELY TILTED TOUGH MOVING ONSHORE IN THE PACIFIC NORTHWEST.
THIS TROUGH WILL AID THE AMPLIFICATION OF A DOWNSTREAM RIDGE OVER
THE ROCKIES, AND THE AMPLIFICATION OF THIS RIDGE WILL SUPPORT THE
SUBSEQUENT DOWNSTREAM AMPLIFICATION OF A TROUGH OVER THE EASTERN US.
EMBEDDED WITHIN THE EASTERN US TROUGH, A CLOSED MIDLEVEL LOW WILL
MIGRATE SOUTHEAST FROM CANADA AT THE START OF THE PERIOD TO BEING
OVER THE UPPER GREAT LAKES BY THE END. AT THE SAME TIME, A WEAK
MIDLEVEL VORTICITY MAXIMUM WILL WEAKEN AS IT MOVES EAST ACROSS THE
NORTHERN GULF COAST AND THE FLORIDA PENINSULA AS IT IS ABSORBED INTO
THE LARGER SCALE LONGWAVE TROUGH.
AT THE SURFACE, A REMNANT COLD FRONT WILL CONTINUE SLOWLY SAGGING
SOUTH ACROSS THE FLORIDA PENINSULA AS A WEAK LOW/ASSOCIATED MCS
MOVES ACROSS THE STATE FROM WEST TO EAST. FARTHER NORTH AND WEST,
ANOTHER LOW WILL MOVE EAST FROM THE NORTHERN PLAINS ACROSS CENTRAL
WISCONSIN INTO LOWER MICHIGAN. AS THIS OCCURS, STRENGTHENING
LOWER-TROPOSPHERIC NORTHERLY FLOW ACROSS THE CENTRAL US WILL PUSH A
COLD FRONT SOUTH ACROSS THE CENTRAL US.
... SOUTHEAST KANSAS/NORTHERN OKLAHOMA INTO SOUTHERN WISCONSIN AND
NORTHWEST INDIANA ...
SOUTHERLY LOW-LEVEL FLOW WILL ATTEMPT TO TRANSPORT GULF MOISTURE
NORTHWARD INTO THE CENTRAL PLAINS NORTHEAST INTO THE UPPER GREAT
LAKES DURING THE MORNING AND EARLY AFTERNOON. THIS WILL OCCUR ALONG
THE WESTERN PERIPHERY OF AN EASTERN US ANTICYCLONE AND AHEAD OF
SOUTH/SOUTHEAST MOVING COLD FRONT. ATOP THIS MOISTURE RETURN,
LARGE-SCALE SUBSIDENCE ASSOCIATED WITH THE EASTERN PORTIONS OF THE
MIDLEVEL RIDGE ACROSS THE ROCKIES WILL SUPPORT WARMING LOWER
TROPOSPHERIC TEMPERATURES. THESE WARM LOW LEVEL TEMPERATURES WILL
PROVIDE A CAP ACROSS THE CENTRAL US WHICH SHOULD INHIBIT
THUNDERSTORM DEVELOPMENT FOR MUCH OF THE DAY AND PROMOTE
UNINTERRUPTED NORTHWARD MOISTURE ADVECTION. THE RESULT WILL BE
SURFACE DEWPOINTS RISING INTO PERHAPS THE LOW 50FS AS FAR NORTH AS
SOUTHERN WISCONSIN BY EARLY AFTERNOON.
AS DIURNAL HEATING WARMS THIS MODIFIED GULF AIRMASS, MUCAPE VALUES
WILL STRUGGLE TO INCREASE TO AROUND 1250 J/KG ACROSS THE SOUTHERN
CENTRAL PLAINS TO AROUND 250 J/KG ACROSS WISCONSIN OWING TO POOR
LAPSE RATES FROM THE WARM LOW-TO-MIDLEVEL TEMPERATURES. THAT SAID,
AT LEAST ISOLATED THUNDERSTORMS SHOULD DEVELOP ACROSS NORTHERN
ILLINOIS/SOUTHERN WISCONSIN TO THE SOUTH OF THE SURFACE LOW, WHERE
SURFACE CONVERGENCE IS GREATEST ALONG THE ADVANCING FRONT. AS THE
EASTERN US MIDLEVEL TROUGH AMPLIFIES, THE ASSOCIATED MIDLEVEL JET
WILL STRENGTHEN DURING THE AFTERNOON AND EVENING ACROSS THE CENTRAL
PLAINS. THIS KINEMATIC PROFILE WILL SUPPORT AT LEAST A MARGINAL WIND
THREAT WITH ANY SUSTAINED THUNDERSTORM.
TO THE SOUTH AND WEST, SLIGHTLY BETTER LOW LEVEL MOISTURE WILL
SUPPORT GREATER INSTABILITY, BUT WARMER TEMPERATURES ALOFT AND
WEAKENING SURFACE CONVERGENCE WILL POTENTIALLY LIMIT THUNDERSTORM
COVERAGE. HOWEVER, A MARGINAL WIND AND HAIL THREAT WILL BE POSSIBLE
WITH ANY SUSTAINED THUNDERSTORM.
.. EASTERN FLORIDA PENINSULA
NUMEROUS THUNDERSTORMS ARE LIKELY DURING THE AFTERNOON AND EVENING
ASSOCIATED WITH THE AFOREMENTIONED SAGGING FRONT AND MIDLEVEL WAVE
MOVING ACROSS THE REGION. HIGH PRECIPITABLE WATER VALUES, LONG
HODOGRAPHS WITHIN THE CLOUD LAYER, AND TALL, SKINNY BUOYANCY
PROFILES WILL SUPPORT THE POTENTIAL FOR A COUPLE OF WET DAMAGING
DOWNBURSTS WITH THE STRONGEST CORES.
.. INTERIOR OREGON
DURING THE LATE AFTERNOON AND OVERNIGHT A VIGOROUS, NEGATIVELY
TILTED MIDLEVEL TROUGH WILL MOVE INTO THE AREA. ALTHOUGH LOW LEVELS
WILL REMAIN VERY DRY, INCREASING MIDLEVEL MOISTURE AND MIDLEVEL
INSTABILITY MAY BE SUFFICIENT FOR A COUPLE OF THUNDERSTORMS. A VERY
DRY SUB-CLOUD LAYER AND STRONG 700-500 MILLIBAR FLOW MAY SUPPORT A
COUPLE OF ISOLATED DAMAGING WIND GUSTS SHOULD THUNDERSTORMS DEVELOP.
CONFIDENCE IN THIS SCENARIO IS TOO LOW TO WARRANT UNCONDITIONAL WIND
PROBABILITIES AT THIS TIME.
..MARSH.. 05/11/2026
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