575
FXUS63 KIWX 050605
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
205 AM EDT FRI JUN 5 2026
KEY MESSAGES
- 40-60% CHANCES FOR SHOWERS AND THUNDERSTORMS FRIDAY AFTERNOON
AND EVENING. ISOLATED SEVERE WEATHER POSSIBLE WITH DAMAGING
WIND AND LARGE HAIL AS THE MAIN THREATS. LOW CONFIDENCE.
- KEEP AN EYE ON THE WEATHER IF YOU HAVE OUTDOOR PLANS ON
SATURDAY! INCREASINGLY HUMID WITH 60-80% CHANCES FOR SHOWERS
AND THUNDERSTORMS SATURDAY AFTERNOON AND EVENING. THERE IS A
SLIGHT RISK FOR SEVERE WEATHER (LEVEL 2 OF 5) WITH DAMAGING
WINDS AND LARGE HAIL AS THE MAIN THREATS. MEDIUM CONFIDENCE.
- DRY AND WARM EARLY NEXT WEEK WITH CONTINUED HIGHS IN THE MID
TO UPPER 80S.
DISCUSSION
ISSUED AT 230 PM EDT THU JUN 4 2026
QUIET, DRY WEATHER PERSISTS TODAY. WITH HIGH PRESSURE HAVING DRIFTED
FROM BEING OVERHEAD YESTERDAY TO NOW OVER THE MID ATLANTIC TODAY,
HIGH CLOUDS ARE DRIFTING IN FROM THE WEST AND WINDS HAVE TURNED
SOUTHERLY AHEAD OF A BIG PATTERN SHIFT IN THE COMING DAYS. SOUTHERLY
SURFACE FLOW IS AIDING IN INCREASED WAA, WITH HIGHS EXPECTED TO BE
IN THE MID TO UPPER 80S THIS AFTERNOON. A TIGHTENING PRESSURE
GRADIENT WILL ALLOW FOR GUSTS UP TO 20 MPH THIS AFTERNOON.
A MID LEVEL TROUGH WILL RIDE THE EDGE OF THE UPPER LEVEL RIDGE
CENTERED OVER THE CENTRAL CONUS ON FRIDAY, BRINGING OUR FIRST OF
SEVERAL OPPORTUNITIES FOR RAIN IN AT LEAST 7-10 DAYS. AS THIS TROUGH
MOVES THROUGH ON FRIDAY AFTERNOON AND EVENING, CHANCES FOR RAIN AND
STORMS INCREASE TO 40-60%. SOME MODELS HAVE STORMS CLIPPING THE
INDIANA-MICHIGAN STATE LINE AS EARLY AS 15-18Z TOMORROW, WHILE
OTHERS HOLD OFF IN FAVOR OF A 21-00Z START TIME. WITH BETTER
MOISTURE NOT ARRIVING INTO OUR AREA UNTIL LATER IN THE DAY
(DEWPOINTS 55-60), I LEAN MORE IN THE FAVOR OF THE LATER TIMEFRAME
BUT WE WILL ALSO HAVE TO MONITOR AND SEE WHAT DEVELOPS IN ILLINOIS
FRIDAY MORNING AND IF IT CLIPS OUR NORTHERN COUNTIES IN THE EARLY
AFTERNOON. SPC DOES HAVE A MARGINAL RISK FOR SEVERE WEATHER (LEVEL 1
OF 5) ALONG AND NORTH OF US 30 ON FRIDAY, 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 500-700 J/KG AND STEEP LOW
LEVEL LAPSE RATES OF 8-9 C/KM WILL SUPPORT ISOLATED INSTANCES OF
DAMAGING WINDS AND HAIL. 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.
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. OUR AREA WILL BE WELL INTO
THE WARM SECTOR SATURDAY WITH BREEZY SOUTHWESTERLY WINDS; DEWPOINTS
WILL INCREASE TO THE UPPER 60S AND MAYBE EVEN LOW 70S IN RESPONSE TO
A STRONG SOUTHWEST LLJ RAMPING UP FRIDAY EVENING AND INTO SATURDAY.
INCREASED MOISTURE COMBINES WITH DAYTIME HEATING (HIGHS IN THE LOW
TO MID 80S) TO SUPPORT SBCAPE OF UP TO 2500 J/KG. HOW MUCH
INSTABILITY WE GET WILL BE HIGHLY CONDITIONAL ON THE AMOUNT OF
CLEARING THAT OCCURS SATURDAY MORNING AND EARLY AFTERNOON. SOME
MODELS KEEP LINGERING RAIN/STORMS/CLOUDS ACROSS OUR AREA SATURDAY
MORNING, WHICH WOULD LIMIT HOW UNSTABLE THE ENVIRONMENT CAN BECOME.
NEVERTHELESS, SOME AMOUNT OF DESTABILIZATION SHOULD OCCUR SATURDAY
AFTERNOON AFTERNOON AFTER 18Z, WITH CHANCES FOR STRONG TO SEVERE
STORMS HIGHEST BETWEEN 18Z-03Z. 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 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.
IT WILL BE DRY AGAIN AS HIGH PRESSURE BUILDS IN ON SUNDAY AND MONDAY
ACROSS THE GREAT LAKES. SUMMER-LIKE TEMPERATURES IN THE MID TO UPPER
80S PERSIST THROUGHOUT ALL OF NEXT WEEK WITH ADDITIONAL DAILY
PERIODIC CHANCES FOR RAIN/STORMS BY MIDWEEK.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 155 AM EDT FRI JUN 5 2026
PREDOMINANTLY VFR CONDITIONS AT THE TERMINALS THIS PERIOD
OUTSIDE OF THUNDERSTORM ACTIVITY WHERE WE COULD SEE BRIEF DROPS
TO MVFR/IFR. UPSTREAM OBSERVATIONS INDICATE SCT/BKN CLOUD DECKS
AROUND 5-6KFT AS OF THIS WRITING, IN ADDITION TO CLOUDS AROUND
25-30KFT. HIGH PRESSURE CONTINUES TO SINK SOUTHEASTWARD THROUGH
THE PERIOD, WITH A TROUGH APPROACHING FROM THE WEST. TIGHTENING
PRESSURE GRADIENT AND DECENT MIXING THIS AFTERNOON SHOULD GIVE
US SW WINDS GUSTING TO AROUND 25-30KTS AT TIMES. OTHERWISE, AS
THE TROUGH MOVES THROUGH THIS AFTERNOON INTO THE OVERNIGHT,
WE'LL SEE ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS. WITHIN
THUNDERSTORMS, MVFR/IFR CONDITIONS ARE POSSIBLE. IT'S POSSIBLE
WE SEE SCATTERED SHOWERS AHEAD OF THE MAIN TROUGH (15Z-18Z) AT
KSBN WITH WAA ONGOING AND STRENGTHENING MOISTURE ADVECTION, SO
ADDED VCSH FOR THAT TIME. MORE IMPACTFUL SHOWERS AND ANY T-STORM
ACTIVITY LOOKS TO HOLD OFF UNTIL AT LEAST 18Z, MORE LIKELY 20Z
(MODELS ARE QUITE VARIABLE). INTERMITTENT ACTIVITY OCCURS THEN
THROUGH THE OVERNIGHT. HANDLED WITH PROB30S FOR T-STORM ACTIVITY
GIVEN LOWER CONFIDENCE. EVEN LESS CERTAINTY AT KFWA AS MODELS
SUGGEST THE PRECIPITATION/STORM ACTIVITY LOOKS TO STRUGGLE WITH
EASTWARD PROGRESSION FROM KSBN. HAVE VCSH STARTING AROUND 21Z,
BUT IT LOOKS LIKE MORE IMPACTFUL WEATHER AND STORM DEVELOPMENT
IS MORE LIKELY AFTER 00Z (MODELS SUGGEST DEVELOPMENT NEARLY
OVERHEAD AROUND 1Z). HAVE VCTS STARTING AT 00Z WITH PROB 30S TO
HANDLE ANY STORMS.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS
EVENING FOR LMZ043-046.
DISCUSSION...JOHNSON
AVIATION...MCD
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