883
FXUS63 KIWX 091045
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
645 AM EDT THU JUL 9 2026
KEY MESSAGES
- THUNDERSTORMS ARE POSSIBLE TODAY AND TONIGHT. A FEW OF THESE
STORMS MAY BE STRONG, CAPABLE OF ISOLATED GUSTY WINDS AND
HEAVY RAIN.
- THUNDERSTORMS ARE ALSO POSSIBLE FRIDAY AND SATURDAY BUT SEVERE
WEATHER IS NOT EXPECTED.
- TURNING HOT AND DRY NEXT WEEK.
DISCUSSION
ISSUED AT 159 AM EDT THU JUL 9 2026
CHALLENGING SHORT-TERM FORECAST TODAY WITH SEVERAL ROUNDS OF
ISO/SCT THUNDERSTORMS POSSIBLE THROUGH TOMORROW. WEAK,
POSITIVELY TILTED MIDLEVEL TROUGH AXIS JUST UPSTREAM WILL CROSS
THE REGION TODAY. ASSOCIATED UPTICK IN SOUTHWESTERLY LOW LEVEL
FLOW WILL ADVECT SOME HIGHER THETA-E AIR INTO THE AREA, THOUGH
BEST MOISTURE REMAINS LOCKED OVER SOUTHERN IL/IN. THIS WILL
YIELD MARGINAL INSTABILITY (SBCAPE'S ROUGHLY 1500-2000 J/KG) BY
LATER TODAY, WHICH IS ENOUGH TO SUPPORT A FEW STRONG STORMS BUT
INSUFFICIENT FOR A WIDESPREAD SEVERE THREAT. THAT IS ESPECIALLY
TRUE GIVEN LACKLUSTER SHEAR AS WELL (0-6KM BULK SHEAR ONLY
AROUND 25 KTS). THE CHALLENGE LIES IN PICKING OUT VERY SUBTLE
FORCING MECHANISMS THAT WILL DICTATE TIMING AND LOCATION/COVERAGE
OVER THE NEXT 24-36 HOURS. CONVECTION JUST TO OUR NORTHWEST
WILL CONTINUE TO WEAKEN THROUGH THE EARLY MORNING BUT REMNANT
OUTFLOW AND APPROACHING MIDLEVEL WAVE COULD SPARK A FEW STORMS
IN OUR NW AS EARLY AS 13Z. NOT EXPECTING MUCH OUT OF THESE GIVEN
LIMITED INSTABILITY BUT STILL WORTH NOTING. BETTER (?) CHANCES
ARRIVE DURING THE LATE AFTERNOON WITH PEAK DIURNAL HEATING BUT
HERE AGAIN THERE IS NOT MUCH TO FOCUS/AUGMENT CONVECTION AND
COVERAGE COULD REMAIN VERY ISOLATED. TONIGHT MAY ACTUALLY
FEATURE THE BEST RAIN CHANCES (FOR OUR SOUTHERN ZONES ANYWAY) AS
MODELS SUGGEST A FEW MCV'S MAY KICK OUT OF MISSOURI AND PERHAPS
CLIP OUR S/SE COUNTIES. OVERALL CONFIDENCE IS LOW HOWEVER GIVEN
BETTER MOISTURE GRADIENT AND MCV TRACK WILL BE SOUTH OF OUR
CWA. ANY SEVERE RISK (DAMAGING WINDS) WOULD LIKELY BE WITH
CONVECTION ARRIVING LATE THIS AFTERNOON AND EVENING WITH HEAVY
RAIN BEING THE PRIMARY CONCERN OVERNIGHT. OVERALL RISK IS LOW
FOR BOTH THOUGH AND WILL LIKELY NEED TO FINE-TUNE POP GRIDS
THROUGH THE DAY AS THESE SUBTLE FORCING MECHANISMS SHOW
THEMSELVES.
LOW CONFIDENCE IN TODAY'S FORECAST CASCADES INTO UNCERTAINTY FOR
FRI AND SAT AS WELL. MODELS SUGGEST MORE CONVECTIVELY-ENHANCED
SHORTWAVES EJECTING OUT OF THE CENTRAL PLAINS BUT LIKELY
TRACKING JUST SOUTH OF OUR AREA. BLENDED INITIALIZATION
MAINTAINS SOME LOW POP'S FOR OUR SOUTHERN ZONES INTO SAT BUT
COULD EASILY SEE THOSE GETTING TRIMMED FURTHER. NO SEVERE
WEATHER EXPECTED WITH ANY STORMS THAT DO MANAGE TO DEVELOP IN
OUR AREA FRI-SAT. LARGE, STRONG RIDGE STILL SLATED TO DEVELOP
OVER THE CENTRAL CONUS EARLY NEXT WEEK AND EVENTUALLY NOSE INTO
OUR REGION. STILL SOME DISAGREEMENT EXACTLY HOW FAR EAST THIS
RIDGE BUILDS AND WHETHER WE MIGHT BE ABLE TO SQUEEZE OUT SOME
PRECIP CHANCES/COOLER TEMPS ON THE E/NE FRINGE. THAT IS LOOKING
LESS LIKELY WITH EACH NEW RUN THOUGH AND A TREND TO SIMPLY HOT
AND DRY CONDITIONS FOR MUCH OF NEXT WEEK SEEMS MORE LIKELY.
AVIATION /12Z TAFS THROUGH 12Z FRIDAY/
ISSUED AT 645 AM EDT THU JUL 9 2026
SCT SHOWERS AND STORMS EXPECTED TO DEVELOP ACROSS THE AREA LATER
THIS MORNING AS A WEAK FRONT APPROACHES THE REGION. HOWEVER,
COVERAGE WILL BE LIMITED BY MARGINAL INSTABILITY AND WEAK
FORCING. SLIGHTLY BETTER CHANCE FOR STORMS ARRIVES DURING THE
LATE AFTERNOON WITH PEAK DIURNAL HEATING BUT EVEN THEN
CONFIDENCE IS NOT HIGH BASED ON LATEST CAM'S. WILL HOLD WITH
JUST A PROB30 MENTION FOR NOW. ADDITIONAL CHANCES FOR STORMS
EXTEND INTO THE OVERNIGHT BUT CONFIDENCE IN TIMING AND COVERAGE
REMAINS TOO LOW TO MENTION IN THE TAF'S AT THIS POINT.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...AGD
AVIATION...AGD
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