212
FXUS63 KIWX 111727
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
127 PM EDT MON AUG 11 2025
KEY MESSAGES
- HOT AND HUMID THROUGH TUESDAY WITH HIGHS IN THE UPPER 80S TO
LOWER 90S AND HEAT INDICES IN THE LOW TO MID 90S.
- A FEW CHANCES FOR SHOWERS AND STORMS THIS WEEK. THE FIRST
CHANCES WILL BEGIN TODAY FOR THE MAINLY NORTHWEST PORTIONS OF
THE CWA AS A FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST.
BETTER CHANCES EXPECTED ACROSS THE AREA WILL BE TUESDAY INTO
WEDNESDAY AS THE FRONT MOVES THROUGH. CONFIDENCE REMAINS LOW
ON EXACT TIMING AND LOCATIONS TO BE IMPACTED.
- HEAT AND HUMIDITY RETURNS NEXT WEEKEND AS RIDGING BEGINS TO
BUILD BACK INTO THE REGION.
DISCUSSION
ISSUED AT 301 AM EDT MON AUG 11 2025
THE STUBBORN RIDGING HAS CONTINUED TO HOLD ON AND HAS BEEN SLOW
TO PROGRESS SOUTH AND EASTWARD. MADE SOME CHANGES TO THE ONGOING
FORECAST WITH THIS FACT IN MIND. PUSHED BACK PRECIPITATION
CHANCES BY SEVERAL HOURS WHICH MAY END UP NOT BEING ENOUGH, BUT
WITH THE POSSIBILITY OF A FEW SHOWERS/STORMS DEVELOPING FURTHER
SOUTH AND WEST AND MOVING NORTHEASTWARD INTO THE AREA THIS
MORNING DID NOT PUSH BACK TIMING FURTHER. THE TIMING BEING
PUSHED BACK WILL ALSO ALLOW FOR TUESDAY TO STILL REMAIN
HOT/HUMID ESPECIALLY FOR THE SOUTHEASTERN PORTIONS OF THE
FORECAST AREA WITH THE SLOWER PROGRESSION OF THE COOL FRONT.
DID NOT CHANGE MUCH FURTHER OUT AS THE BETTER CHANCES OF
SHOWERS/STORMS STILL LOOKS TO BE THE TUESDAY INTO THE WEDNESDAY
TIME PERIOD WITH THE FRONTAL BOUNDARY PASSAGE SOUTHEASTWARD
THROUGH THE CWA. THE BRIEF REPRIEVE FROM THE HOTTER TEMPERATURES
STILL LOOKS GOOD ON WEDNESDAY AND THURSDAY BEFORE BROAD RIDGING
OVER THE SOUTHERN CONUS LOOKS TO BUILD NORTH AND EASTWARD INTO
THE REGION BEGINNING FRIDAY. HOT AND HUMID CONDITIONS RETURN
ONCE AGAIN FOR SATURDAY AND SUNDAY. HIGHS AGAIN GETTING BACK
INTO THE UPPER 80S AND LOW 90S AND DEW POINTS PUSHING BACK INTO
THE 70S BEGINNING SATURDAY THROUGH THE WEEKEND. THE
HEAT/HUMIDITY MAY EVEN STICK AROUND INTO THE BEGINNING OF NEXT
WEEK, HOWEVER STILL A BIT OF UNCERTAINTY TO THE TIMING OF A
TROUGH OVER THE NORTHERN PLAINS PUSHING SOUTHEASTWARD INTO THE
GREAT LAKES REGION.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 126 PM EDT MON AUG 11 2025
REMNANT OUTFLOW BOUNDARIES AND WEAK AREAS OF VORTICITY MOVED THROUGH
OUR NORTHWESTERN AREAS THIS MORNING AND THERE IS SOME CHANCE OF AN
EASTWARD PUSH OF THIS FORCING FOR THE AFTERNOON. HI-RES MODELS DID
NOT CATCH ONTO MORNING CONVECTION WITHIN ADVANCEMENT OF HIGHER THETA-
E AIRMASS THAT CAUSED WEAK SHOWERS AND STORMS, BUT THESE DID DIE ON
OUR WESTERN EDGE OF THE FORECAST AREA. WITHIN WEAK AREA OF
INSTABILITY, THERE COULD BE GROWTH TO THIS AREA, BUT EXTENT OF
UPSCALE GROWTH IS UNCERTAIN IN ANY DIRECTION ESPECIALLY GIVEN EXTENT
OF RIDGING OVERHEAD AND LINGERING DRY AIR FROM RECENT EXTENDED
PERIOD OF DRY AIR. WARM ADVECTION PRECIP APPEARS TO BE CREATING MVFR
FLIGHT CONDITIONS UNDERNEATH IT, BUT STILL, IT'S UNCERTAIN IF THAT
ENDS UP HITTING SBN OR FWA. AT THIS POINT, FEEL IT'S MOST PRUDENT TO
KEEP GROUPS FOR THIS OUT OF THE TAFS UNTIL SOMETHING ALLOWS FOR MORE
CONFIDENCE. AMENDMENTS WILL LIKELY BE NECESSARY. ANOTHER AREA OF
RAIN AND PERHAPS SOME THUNDERSTORMS ARRIVES BETWEEN 00Z AND 06Z AS
THETA-E AXIS SLIDES NORTHWARD. THIS COULD PROVIDE ANOTHER
OPPORTUNITY FOR LOWER FLIGHT CONDITIONS GIVEN COVERAGE OF RAIN AND
POSSIBLE INTENSITY OF SHOWERS/STORMS, BUT IT'S UNCERTAIN IF IT WILL
HIT SBN OR STAY NORTH OF IT. FEEL IT IS MOST PRUDENT TO USE PROB30
GROUP FOR THAT. MOIST AXIS THEN ADVANCES EASTWARD LATER TUESDAY
NIGHT INTO WEDNESDAY MORNING WHICH STILL PROVIDES MORE OPPORTUNITIES
FOR RAIN AT SBN. HOWEVER, FLIGHT CONDITIONS DO NOT APPEAR TO BE
AFFECTED IN A PREVAILING THREAT AND DON'T HAVE ENOUGH CONFIDENCE
GIVEN MODEL UNCERTAINTY TO PUT THIS THREAT IN EITHER. STILL EXPECT
SOUTHWEST WIND TRAJECTORIES WITH PERIODS OF AROUND 10 KTS SUSTAINED
DURING PEAK HEATING TIMES.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...ANDERSEN
AVIATION...ROLLER
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