209
FXUS63 KIWX 101629
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1229 PM EDT MON AUG 10 2026
KEY MESSAGES
- SEVERAL ROUNDS OF STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE
INTO TUESDAY. DAMAGING WINDS AND LARGE HAIL ARE THE MAIN
CONCERNS, BUT AN ISOLATED TORNADO OR 2 IS POSSIBLE.
- FLOODING CONCERNS MAY INCREASE DEPENDING ON RAINFALL AMOUNTS
ACROSS THE AREA WITH EACH ROUND OF STORMS.
- SEASONABLE TEMPERATURES ARE EXPECTED TO PERSIST.
DISCUSSION
ISSUED AT 111 AM EDT MON AUG 10 2026
FOCUS OF DISCUSSION AND ANY FORECAST UPDATES WILL BE ON NEXT 24 TO
36 HOURS WITH REGARDS TO SEVERE AND HYDROLOGIC CONCERNS. GETTING
DISCUSSION OUT EARLY TO TO POTENTIAL STORMS OVER NEXT COUPLE OF
HOURS.
WE ARE MONITORING A CLUSTER OF THUNDERSTORMS FROM SE WI INTO
NORTHERN IL. WHILE SOME OCCASIONAL SEVERE REPORTS CAME FROM EARLIER
STORMS, THE MAIN STORM OF INTEREST (HP SUPERCELL) IS ROOTED ON THE
OUTFLOW BOUNDARY FROM THE EARLIER STORMS WITH SOME HINTS AT THIS
MOVING MORE SE WITH TIME. OTHER STORMS CONTINUE TO TRY TO DEVELOP
AND EXPAND, INCLUDING FAR NW PARTS OF THE AREA. THIS LEAVES A LOT OF
UNCERTAINTY AS TO WHAT OCCURS OVERNIGHT. PLENTY OF INSTABILITY
REMAINS ACROSS THE AREA, BUT NEAR SFC INHIBITION MAY LIMIT WIND
POTENTIAL OVERNIGHT. SUFFICE TO SAY, RISK OF SEVERE REMAINS IN PLAY
ACROSS THE AREA. FOR THE LATEST UPDATES ON THE MESOSCALE FEATURES,
MONITOR SPC PRODUCTS. IN ADDITION, A FLASH FLOOD WATCH WAS ISSUED
EARLIER TO COVER SEVERAL COUNTIES TO COVER THE RECENT RAINFALL AND
POTENTIAL FOR SOME AREAS SEEING MORE HEAVY RAIN OVERNIGHT. THIS IS
CURRENTLY IN EFFECT UNTIL 11 AM EDT, BUT GIVEN THE CONCERNS OF THE
CONVECTIVE EVOLUTION OVERNIGHT NO CHANGES ARE PLANNED AT THIS TIME.
IN THE WAKE OF THE OVERNIGHT/EARLY AM STORMS, THE ATMOSPHERE WILL
RECHARGE ONCE AGAIN WITH PLENTY OF CAPE AND SUFFICIENT SHEAR TO BRING
YET ANOTHER SEVERE THREAT MONDAY AFTERNOON AND EVENING. MUCH LIKE
TODAY, THE MAIN THREAT WILL BE DAMAGING WIND ALONG WITH SOME LARGE
HAIL. IF ANY OUTFLOW BOUNDARIES LINGER IN THE AREA, THESE COULD HELP
WITH A LOCALIZED TORNADO THREAT. ALSO IN PLAY WILL BE THE CONTINUED
THREAT OF HEAVY RAINFALL AS PWATS REMAIN ABOUT 1.75" AND WARM CLOUD
DEPTHS OF 14 K TO 15KFT. MAY NEED TO EXPAND THE FLOOD WATCH IN AREA
AND TIME DEPENDING ON WHAT EVOLVES OVERNIGHT. SADLY, TRENDS IN THE
MODELS DO SHOW YET MORE STORMS DEVELOPING LATER MONDAY EVENING INTO
TUESDAY MORNING (POSSIBLY THE 4TH ROUND OF STORMS SINCE SUNDAY
EVENING). NOT EVEN GOING TO TRY TO DO ANYTHING IN THE FORECAST WITH
THIS GIVEN THE PLETHORA OF CHALLENGES FROM PREVIOUS ROUNDS OF STORMS
THAT CANNOT BE FULLY RESOLVED THIS FAR OUT.
DEEPENING ON THE LOCATION OF THE STATIONARY BOUNDARY TUESDAY, ONE
MORE ROUND OF CONVECTION COULD OCCUR FOCUSED SOUTH OF US-30. AGAIN,
NO CHANGES TO FORECAST WITH REGARDS TO THIS, JUST SOMETHING TO KEEP
IN MIND WITH THE FLOOD THREAT POSSIBLY STILL THERE.
BEYOND TUESDAY NIGHT, MODELS SEEM TO PUSH THE EFFECTIVE BOUNDARY
SOUTH OF THE AREA TO GIVE US A REPRIEVE FROM THE RAIN AND STORMS.
HOWEVER, THE OVERALL UPPER LEVEL FLOW DOESN'T CHANGE MUCH SO LOW
CONFIDENCE AT THIS POINT AND MODEL BLEND WILL BE LEFT ALONE.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1228 PM EDT MON AUG 10 2026
MVFR STRATOCU IN THE VICINITY OF A FRONTAL BOUNDARY SHOULD MIX
INTO LOW VFR WITH SOME ADDITIONAL HEATING THIS AFTERNOON. MAIN
FOCUS OTHERWISE IS ON THE CONVECTIVE POTENTIAL LATE THIS
AFTERNOON INTO TONIGHT. LATEST OBSERVATIONAL AND MODEL DATA
SUGGEST THE LATE AFTERNOON AND EVENING FOR THE BEST OPPORTUNITY
FOR SCATTERED CONVECTION AS A WEAK IMPULSE APPROACHES FROM THE
WEST AMID AMPLE MUCAPE. BRIEF IFR/LIFR CONDITIONS AND GUSTY
WINDS POSSIBLE IF STORMS IMPACT THE TERMINALS.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...FISHER
AVIATION...STEINWEDEL
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page