867
FXUS63 KIWX 060041
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
841 PM EDT FRI JUN 5 2026
KEY MESSAGES
- ANOTHER ROUND OF SHOWERS AND STORMS IS EXPECTED LATE TONIGHT.
ISOLATED SEVERE WEATHER IS POSSIBLE, WITH GREATEST CHANCES
AFTER 2 AM EDT SATURDAY. CONFIDENCE IS LOW.
- A FEW STRONG STORMS ARE POSSIBLE LATE SATURDAY AFTERNOON INTO
SATURDAY EVENING, MAINLY ALONG/SOUTH OF US-24.
- DRY AND WARM EARLY NEXT WEEK WITH CONTINUED HIGHS IN THE MID
TO UPPER 80S. FIRST 90+ DEGREE DAY OF THE YEAR POSSIBLE BY
LATE NEXT WEEK.
UPDATE
ISSUED AT 840 PM EDT FRI JUN 5 2026
UPDATED POP/QPF/SKY GRIDS TO REFLECT LATEST TRENDS IN
OBSERVATIONAL DATA AND HI-RES CAM'S. FIRST ROUND OF CONVECTION
IS NOW EXITING BUT MORE STORMS ARE EXPECTED LATE TONIGHT AS A
WEAK FRONTAL BOUNDARY APPROACHES THE AREA (CURRENTLY DRIVING
CONVECTION ACROSS WI). INCREASING LOW LEVEL MOISTURE, SHEAR AND
MIDLEVEL LAPSE RATES NEAR 7 C/KM SUGGEST SOME LOW-END SEVERE
RISK DESPITE LATE-NIGHT TIMING. BOUNDARY-LAYER STABILIZATION
WILL BE A SIGNIFICANT LIMITING FACTOR BUT SOME HAIL AND ISOLATED
GUSTY WINDS CAN'T BE RULED OUT ROUGHLY 06-12Z. TRENDS FOR
TOMORROW SUGGEST A LATER START AND SHIFTING FURTHER SOUTH. BEST
STORM CHANCES APPEAR IN OUR SOUTHERN HALF DURING THE LATE
AFTERNOON/EVENING. AGAIN AN ISOLATED SEVERE STORM IS POSSIBLE IF
DECENT INSTABILITY BUILDS IN OUR CWA.
DISCUSSION
ISSUED AT 153 PM EDT FRI JUN 5 2026
A DECAYING MCS WILL BRING INCREASING CHANCES FOR RAIN AND A FEW
STORMS THIS AFTERNOON AND EVENING ASSOCIATED WITH A MID LEVEL
TROUGH. HIGHEST CHANCES OF 60-80% WILL BE ACROSS LOWER MICHIGAN.
DESPITE THE APPROACHING LINE OF SHOWERS AND STORMS ON RADAR THIS
AFTERNOON, THE ENVIRONMENT IS VERY LACKLUSTER FOR ANY SEVERE
WEATHER BEFORE 06Z TONIGHT OUTSIDE OF AN ISOLATED INSTANCE OR
TWO FOR DAMAGING WIND. INVERTED V FORECAST SOUNDINGS OVER THE
FORECAST AREA DEPICT VERY MEAGER INSTABILITY (<500 J/KG) AND MID
LEVEL LAPSE RATES (<6C/KM). SPC DOES HAVE A MARGINAL RISK FOR
SEVERE WEATHER (LEVEL 1 OF 5) ALONG AND NORTH OF US 24 TODAY AND
TONIGHT, ALTHOUGH CONFIDENCE IN SEVERE WEATHER OCCURING IS LOW.
GIVEN A FAIRLY UNIDIRECTIONAL VERTICAL WIND PROFILE, 0-6KM
SHEAR WILL ONLY BE ABOUT 20 KTS. WITH WEAKER SHEAR, THE FAVORED
STORM MODE WILL BE MULTICELL CLUSTERS OR LINE SEGMENTS. MODERATE
DCAPE OF AROUND 500 J/KG AND STEEP LOW LEVEL LAPSE RATES OF 8-9
C/KM WILL SUPPORT ISOLATED INSTANCES OF DAMAGING WINDS. WITH
PWATS AROUND 1.5 TO 2", EVEN IF STORM CLUSTERS ARE NOT SEVERE,
THEY WILL LIKELY BE EFFICIENT RAINFALL PRODUCERS WITH RAINFALL
RATES IN EXCESS OF 1"/HR.
DEWPOINTS WILL INCREASE INTO THE LOW TO MID 60S TONIGHT IN RESPONSE
TO A STRONG LLJ RAMPING UP THIS EVENING AND INTO SATURDAY. WITH
BETTER MOISTURE TRANSPORT AND INCREASING BULK SHEAR UP TO 35 KTS,
AFTER 06Z TONIGHT, THE ENVIRONMENT BECOMES MODERATELY FAVORABLE
FOR SEVERE WEATHER. LOW LEVEL LAPSE RATES IMPROVE AS WELL TO
AROUND 7- 8C/KM. HI-RES MODEL GUIDANCE HAS A LARGE SPREAD OF
SOLUTIONS FOR WHAT COULD HAPPEN RANGING FROM NOTHING TO A
SUSTAINED LINE OF STORMS ACROSS NORTHERN INDIANA SLOWLY MOVING
SOUTHWARD FROM 06-12Z. I AM NOT FULLY CONFIDENT ON WHAT THE
CORRECT SOLUTION WILL BE, BUT GIVEN THE DECENTLY FAVORABLE
ENVIRONMENT DESPITE THE LOSS OF DIURNAL HEATING, I WOULD LEAN
TOWARDS ISOLATED STRONG TO SEVERE STORMS BEING POSSIBLE
OVERNIGHT WITHIN THE MARGINAL RISK.
KEEP AN EYE ON THE WEATHER IF YOU HAVE OUTDOOR PLANS ON SATURDAY!
AHEAD OF AN APPROACHING COLD FRONT, STRONG TO SEVERE STORMS WILL BE
POSSIBLE SATURDAY AFTERNOON AND EVENING DURING PEAK HEATING HOURS.
OUR AREA WILL BE WELL INTO THE WARM SECTOR SATURDAY WITH BREEZY
SOUTHWESTERLY WINDS AND DEWPOINTS SOARING TO AROUND 70 DEGREES.
INCREASED MOISTURE COMBINES WITH DAYTIME HEATING (HIGHS IN THE LOW
TO MID 80S) TO SUPPORT SBCAPE OF UP TO 1000-1500 J/KG. HOW MUCH
INSTABILITY WE GET WILL BE HIGHLY CONDITIONAL ON WHAT OCCURS TONIGHT
INTO EARLY SATURDAY MORNING. NEVERTHELESS, CONVECTIVE INITIATION
SHOULD OCCUR AFTER MIDDAY SATURDAY WITH THE BEST CHANCES FOR
SCATTERED STRONG TO SEVERE STORMS BETWEEN 18Z-03Z. COVERAGE AND
INTENSITY OF STORMS, INCLUDING SEVERE POTENTIAL, WILL BE DRIVEN BY
HOW MUCH THE ATMOSPHERE CAN RECOVER FROM WHATEVER HAPPENS OVERNIGHT
INTO SATURDAY MORNING. A SLIGHT RISK (LEVEL 2 OF 5) FOR SEVERE
WEATHER IS IN PLACE ACROSS NORTHWEST OHIO, WITH A MARGINAL RISK
(LEVEL 1 OF 5) FOR THE REST OF THE FORECAST AREA. SEVERE POTENTIAL
IS GREATEST IN NW OHIO BECAUSE 1) THIS AREA MAY NOT BE IMPACTED BY
OVERNIGHT CONVECTION AND 2) THIS AREA WILL HAVE THE LONGEST TIME TO
HEAT UP AND DESTABILIZE SATURDAY AS THE COLD FRONT TAKES ITS TIME
MOVING IN FROM NORTHWEST TO SOUTHEAST. CONFIDENCE IS MEDIUM IN
SEVERE WEATHER OCCURING (GIVEN MORNING UNCERTAINTY) BUT THE
ENVIRONMENT WILL BE MORE FAVORABLE THAN FRIDAY. STEEP LOW LEVEL
LAPSE RATES OF 9C/KM AND 0-6KM SHEAR OF 35-40 KTS WILL SUPPORT
DAMAGING WINDS AND LARGE HAIL AS THE MAIN THREATS WITH ANY STORMS.
IT WILL BE DRY AGAIN AS HIGH PRESSURE BUILDS IN ON SUNDAY AND MONDAY
ACROSS THE GREAT LAKES. AS THE UPPER LEVEL RIDGE BUILDS ACROSS THE
CENTRAL CONUS, SUMMER-LIKE TEMPERATURES IN THE MID TO UPPER 80S
PERSIST THROUGHOUT ALL OF NEXT WEEK WITH THE FIRST 90+ DEGREE DAY
POSSIBLE FOR MANY LOCATIONS BY THE END OF THE WEEK. IN ADDITION,
THERE WILL BE DAILY PERIODIC CHANCES FOR RAIN/STORMS BY MID TO LATE
IN THE WEEK.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 840 PM EDT FRI JUN 5 2026
A MIDLEVEL TROUGH LIFTING THROUGH THE GREAT LAKES WILL SEND A
SLOW-MOVING, WEAK SURFACE FRONT THROUGH THE AREA LATE TONIGHT
INTO SATURDAY. NUMEROUS SHOWERS WITH A FEW EMBEDDED
THUNDERSTORMS ARE EXPECTED LATE TONIGHT INTO EARLY SAT MORNING.
CONFIDENCE IN EXACT TIMING REMAINS ON THE LOW SIDE BUT BEST
CHANCES APPEAR TO BE AROUND 08-11Z. SOME BRIEF MVFR CEILINGS ARE
LIKELY WITH THIS ACTIVITY, ESPECIALLY AT KSBN. A SECOND ROUND OF
STORMS IS POSSIBLE AT KFWA SAT EVENING BUT CONFIDENCE IS TOO
LOW TO MENTION THIS FAR OUT.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
UPDATE...AGD
DISCUSSION...JOHNSON
AVIATION...AGD
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