116  
FXUS63 KIWX 272250  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
650 PM EDT THU MAR 27 2025  
   
KEY MESSAGES
 
 
- MILD OVERNIGHT WITH AN INCREASING CHANCE OF SHOWERS AND  
THUNDERSTORMS PRIOR TO DAYBREAK.  
 
- DRYING OUT FRIDAY AFTERNOON BUT BECOMING BREEZY WITH SOUTHWEST  
GUSTS UP TO 40 MPH.  
 
- WARM BUT RAINY WEEKEND WITH A CHANCE OF THUNDERSTORMS AS WELL.  
 

 
   
DISCUSSION
 
 
ISSUED AT 240 PM EDT THU MAR 27 2025  
 
CYCLOGENESIS IS UNDERWAY OVER THE CENTRAL PLAINS THIS AFTERNOON. IN  
THE WARM SECTOR, EXTENDING INTO FAR WESTERN IL, CONVECTION IS  
UNDERWAY AND IS ANTICIPATED TO BECOME REINVIGORATED OVERNIGHT. THIS  
BOOST IS COURTESY OF A BLOSSOMING 60-KNOT 850-MB JET. WHILE THE  
PRIMARY INSTABILITY POOL WILL RESIDE OVER IOWA AND WESTERN ILLINOIS,  
A BROAD CORRIDOR OF 500 J/KG IS NOTED ON THE 12Z HREF PRIMARILY WEST  
OF I-69 OVERNIGHT. SEVERE WEATHER IS NOT ANTICIPATED, THOUGH PEA  
SIZED HAIL CANNOT BE RULED OUT AS OBSERVED EARLIER TODAY ALONG THE  
ILX-LOT FORECAST BORDER.  
 
AS THE NOSE OF THIS JET MOVES EAST, COVERAGE OF SHOWERS AND  
THUNDERSTORMS WILL DIMINISH THROUGH FRIDAY MORNING. THERE WILL BE A  
BRIEF PERIOD OF GUSTY SOUTHWEST WIND (35 TO 40 MPH) IN THE AFTERNOON  
AS CLOUD COVER DECREASES AND WE MIX-DOWN STRONG LOW-LEVEL WINDS. THE  
HREF INDICATES ONLY A 10% TO 20% CHANCE OF WIND GUSTS GREATER THAN  
45 MPH FRIDAY AFTERNOON.  
 
BY SATURDAY MORNING, A LARGE PORTION OF OUR AREA COULD BE SPLIT BY  
1) RAIN TO THE NORTH OVER CENTRAL MICHIGAN (DRIVEN BY FRIDAY'S WARM  
FRONT NOW RELOCATED) AND 2) RENEWED MOISTURE ADVECTION TO OUR SOUTH  
ACROSS CENTRAL IN. LOW PRESSURE EMERGING FROM THE ROCKIES OPPOSES AN  
OFFSHORE SOUTHEAST US RIDGE RESULTING IN A STEADY DOSE OF MOISTURE  
TRANSPORT. THERE WILL BE SOME DRY HOURS SATURDAY, ESPECIALLY ALONG  
THE NORTH OF THE US 30 CORRIDOR. HOWEVER, BROAD CHANCE POPS REMAIN  
IN THE ABSENCE OF HIGH RESOLUTION GUIDANCE AT THIS TIME. THUNDER  
APPEARS UNLIKELY SATURDAY OWING TO A LACK OF INSTABILITY. OVERNIGHT,  
RAIN LIFTS INTO NORTHWEST OHIO. RAIN IS PERHAPS MOST WIDESPREAD  
SUNDAY AS THE LOW MOVES ACROSS SOUTHERN LAKE MICHIGAN. MEAGER  
INSTABILITY RETURNS AS WELL BRINGING THUNDER BACK TO THE FORECAST.  
PAIRED WITH ABOUT 30 KNOTS OF SHEAR, I IMAGINE AT LEAST A SLIVER OF  
OUR FORECAST AREA WILL REMAIN IN A CONVECTIVE OUTLOOK BY THE STORM  
PREDICTION CENTER. HOWEVER, KNOW THAT THE OVERALL SEVERE WEATHER  
RISK APPEARS LOW FOR OUR LOCAL AREA.  
 
SHARPLY COLDER SUNDAY NIGHT AND MONDAY WHEN HIGHS WILL ONLY BE IN  
THE 40S (COMPARED TO 70S FRIDAY THROUGH SUNDAY). MILDER BY MIDWEEK  
AS ZONAL FLOW RESUMES. AFTER MONDAY MORNING, THE NEXT CHANCE FOR  
WIDESPREAD RAIN IS WEDNESDAY.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z SATURDAY/
 
 
ISSUED AT 638 PM EDT THU MAR 27 2025  
 
VFR AND MAINLY DRY CONDITIONS OUTSIDE OF A ISOLATED SPRINKLE  
THIS EVENING. OVERNIGHT AND INTO FRIDAY MORNING, AHEAD OF A  
WARM FRONTAL BOUNDARY PUSHING NORTHWARD INTO THE REGION,  
SHOWERS AND EVEN AN EMBEDDED THUNDERSTORM OR TWO WILL BE  
POSSIBLE AFTER 07-08Z FRIDAY AND LOWERING OF CIGS WITH THE  
FRONTAL PASSAGE BY LATE MORNING TO EARLY AFTERNOON WILL BRING  
MVFR CATEGORIES AND IN HEAVIER SHOWERS SLIGHTLY LOWERED CIGS  
MAY TEMPORARILY DROP TO IFR LEVELS, ESPECIALLY FOR KSBN. AFTER  
16-17Z FRIDAY WE BEGIN TO SEE CIGS IMPROVE AND VFR CONDITIONS  
RETURN. POST FRONTAL WE WILL SEE GUSTY SOUTHWEST WINDS WITH  
GUSTS UP TO 27 KNOTS.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
OH...NONE.  
MI...NONE.  
MARINE...SMALL CRAFT ADVISORY FROM 3 PM FRIDAY TO 4 AM EDT SATURDAY FOR  
LMZ043-046.  
 

 
 

 
 
DISCUSSION...BROWN  
AVIATION...ANDERSEN  
 
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