127
FXUS63 KIWX 042354
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
754 PM EDT THU SEP 4 2025
KEY MESSAGES
- BREEZY AND BRIEFLY WARMER ON FRIDAY WITH WESTERLY GUSTS OF 25 TO
35 MPH.
- MAINLY DRY OVER THE NEXT 7 DAYS.
- COOL TEMPERATURES THIS WEEKEND INTO EARLY NEXT WEEK.
- DANGEROUS SWIMMING CONDITIONS EXPECTED FOR LAKE MICHIGAN BEACHES
THROUGH SATURDAY.
DISCUSSION
ISSUED AT 206 PM EDT THU SEP 4 2025
A COMPACT/ROBUST SHORTWAVE AND DEEPENING SURFACE LOW PRESSURE
CENTER WILL SLINGSHOT EAST THROUGH THE NORTHERN GREAT LAKES TONIGHT
INTO FRIDAY, EVENTUALLY GETTING ABSORBED INTO AN ONTARIO UPPER LOW
LATER FRIDAY-FRIDAY NIGHT. ANY WARM ADVECTION PRECIPITATION SHOULD
MISS NORTH GIVEN THE TRACK, WITH THE MAIN IMPACT LOCALLY BEING A
RAMPING PRE-FRONTAL KINEMATIC FIELD LATER TONIGHT INTO FRIDAY
MORNING. HREF GUIDANCE SUGGESTS A ~40 KT LLJ DURING THIS TIME
WHICH COULD PROMOTE BRIEF GUSTIER WEST WINDS (30-40 MPH) MID MORNING
THROUGH EARLY AFTERNOON AS GREATER MIXING COMMENCES. THE LOW LEVEL
WIND FIELD DOES DIMINISH FRIDAY AFTERNOON AS THE TRAILING SFC
TROUGH TRACKS THROUGH, THOUGH CAA AND INCREASED MIXING DEPTHS
WILL STILL KEEP THINGS GUSTY. MODELS DO HINT A BRIEF FGEN FLARE
UP OVER SOUTHERN PORTIONS OF THE FORECAST FRIDAY AFTERNOON. THE
SUB 700 MB AIR IS VERY DRY HOWEVER SUGGESTING VIRGA/SPRINKLES
AT WORST. TIMING OF THE FRONT SHOULD FAVOR HIGHS RANGING FROM
THE MID 60S NORTHWEST TO THE UPPER 70S SOUTHEAST OTHERWISE.
UPPER TROUGHING WILL LINGER OVER THE REGION INTO THIS WEEKEND WITH
COOLER WEATHER PERSISTING. SEVERAL SMALL AMPLITUDE IMPULSES WILL
SWING THROUGH IN THIS REGIME WITH NON-ZERO CHANCES FOR A FEW
SPRINKLES OR LIGHT SHOWERS, BEST CHANCES (10%) IN LOWER MI THANKS TO
SOME LAKE MI MOISTURE FLUX SATURDAY NIGHT INTO SUNDAY. GIVEN THE
WEAK NATURE TO THESE WAVES, AND THE OVERALL DEARTH OF MOISTURE, WILL
CONTINUE WITH A DRY FORECAST FOR MOST THROUGH THE WEEKEND. SURFACE
HIGH PRESSURE THEN FOLLOWS IN BY EARLY NEXT WEEK WITH TEMPERATURES
ON A GRADUAL WARMING TREND.
AVIATION /00Z TAFS THROUGH 00Z FRIDAY/
ISSUED AT 710 PM EDT THU SEP 4 2025
A VERY DEEP LOW WAS OVER ONTARIO, SOMEWHAT NORTH OF LAKE
SUPERIOR. A STRONG COLD FRONT ASSOCIATED WITH THIS LOW WAS WELL
UPSTREAM, AND WAS JUST ENTERING NORTHWEST IOWA. AHEAD OF THE
FRONT, SOUTHWEST FLOW AT THE SURFACE WAS PREVAILING. WINDS
SHOULD INCREASE ACROSS NORTHERN INDIANA OVERNIGHT AS THE FRONT
APPROACHES. THE LATEST HRRR BRINGS THE FRONT THROUGH NORTHERN
INDIANA BETWEEN ABOUT 12Z AND 15Z. THE WINDS SHOULD SHIFT TO THE
WEST AT THIS TIME WITH WIND GUSTS UP TO 30 KNOTS. THERE WILL BE
VERY LIMITED MOISTURE TO WORK WITH, SO PRECIPITATION AND LOW
CLOUDS ARE NOT EXPECTED.
IWX WATCHES/WARNINGS/ADVISORIES
IN...BEACH HAZARDS STATEMENT FROM 4 AM CDT FRIDAY THROUGH LATE
FRIDAY NIGHT FOR INZ103.
OH...NONE.
MI...BEACH HAZARDS STATEMENT FROM 5 AM EDT FRIDAY THROUGH LATE
FRIDAY NIGHT FOR MIZ177-277.
MARINE...GALE WARNING FROM 2 AM TO 11 AM EDT FRIDAY FOR LMZ043-046.
DISCUSSION...STEINWEDEL
AVIATION...SKIPPER
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