111
FXUS63 KIWX 061619
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1219 PM EDT SAT JUN 6 2026
KEY MESSAGES
- THERE IS A MARGINAL TO SLIGHT RISK FOR SEVERE STORMS TODAY,
ESPECIALLY BETWEEN 2PM AND 11 PM EDT. CONFIDENCE IS MEDIUM.
DAMAGING WINDS AND LARGE HAIL ARE THE MAIN THREAT. FREQUENT
LIGHTNING AND HEAVY RAIN ARE ALSO EXPECTED.
- NEARLY DAILY CHANCES (20-50 PERCENT)FOR SHOWERS AND STORMS
THROUGH NEXT WEEKEND, ESPECIALLY MONDAY INTO TUESDAY NIGHT
(50-90 PERCENT).
- HOT AND HUMID, ESPECIALLY FROM WEDNESDAY INTO NEXT WEEKEND.
HEAT INDICES WILL BE AT OR SLIGHTLY ABOVE 100 DEGREES AT
TIMES. HIGHS WILL BE IN THE UPPER 80S, LOW-MID 90S. LOWS IN
THE 60S, LOW-MID 70S.
DISCUSSION
ISSUED AT 505 AM EDT SAT JUN 6 2026
OUR CWA IS STILL IN A MARGINAL TO SLIGHT RISK FOR TODAY, THOUGH THE
SLIGHT RISK WAS EXPANDED INTO PORTIONS OF IN. GENERALLY THE SLIGHT
RISK EXTENDS FROM SAN PIERRE, IN (STARKE CO) THROUGH MILFORD, IN
(KOSCIUSKO CO) INTO PIONEER, OH (WILLIAMS CO, IN) AND SOUTHEASTWARD
OF THAT LINE. FOR THE AFTERNOON, FAR NORTHERN BERRIEN COUNTY, MI IS
IN GENERAL THUNDER VS. MARGINAL RISK (ONGOING STORMS ARE MAIN
THREAT). THE GREATEST THREAT FOR SEVERE WEATHER WILL BE MID TO LATE
AFTERNOON INTO THE EVENING (2-11 PM EDT). STRONG STORMS ARE STILL
POSSIBLE THROUGH THIS MORNING/EARLY AFTERNOON.
A BROAD LINE OF CONVECTION DROPPED SOUTHEASTWARD FROM WI ACROSS LAKE
MI AND AS OF THIS WRITING (3:45 AM ET) IS JUST DROPPING INTO THE
SOUTH BEND, IN TO UNION CITY, MI AREA. LIGHTNING INTENSITY HAS
TAPERED OFF IN THE LAST COUPLE HOURS AND BREAKS ARE BEGINNING TO
SHOW WITHIN THE LINE AS IT CONTINUES TO WEAKEN. STILL, THE STORMS
ARE DROPPING INTO AN AREA OF STEEPER MID LEVEL LAPSE RATES AND
STRONG MOISTURE TRANSPORT, WITH DEWPOINTS IN THE MID-UPPER 60S AND
EVEN A COUPLE NEARING 70 (KPPO, KANQ). WE'RE ALSO SEEING THE BASE OF
THE 500 MB TROUGH APPROACHING, WITH PVA INCREASING AND A JET STREAK
ALOFT. BULK EFFECTIVE SHEAR LOOKS TO BE IN THE 30-40 KNOT RANGE
THROUGH THE NEXT 6 HOURS AT LEAST. WE'VE ALSO SEEN DEVELOPMENT IN
SCATTERED CONVECTION AHEAD OF THE LINE AS THE FORCING/MOISTURE
TRANSPORT (LLJ) HAVE INCREASED WITH TIME. THE MAIN COLD FRONT IS
STILL FURTHER NORTH ACROSS THE NORTHERN LOWER PENINSULA DRAPED DOWN
TO SOUTHERN WI/NW IL. CONVECTION WELL AHEAD OF THAT EXTENDS ALL THE
WAY INTO IL NEAR KPIA NORTH TO CHICAGO...AND IS NOW IN NW IN AS FAR
INLAND AS GOSHEN/ROCHESTER. EXPECT THIS AREA OF CONVECTION TO
CONGEAL WITH THE INCOMING LINE, SO HAVE LIKELY/CATEGORICAL (55+)
POPS DROPPING SOUTHEASTWARD THROUGH THE LATE MORNING.
AT THE MOMENT, WE HAVE AN SPS OUT FOR THE STORM COMING OFF LAKE MI
FOR HALF INCH HAIL AND 50 MPH WINDS...WITH A SMW OUT FOR LAKE MI
(EXPIRING WITHIN THE HOUR). THIS STORM IS THE STRONGEST AT THIS
MOMENT. OTHERWISE, WHILE A FEW STORMS COULD BE STRONG DON'T EXPECT
WIDESPREAD SEVERE WEATHER THROUGH THE MORNING. IN THOSE CASES
PERHAPS SOME 40-50 MPH WINDS AND SMALL HAIL. FREQUENT LIGHTNING AND
HEAVY DOWNPOURS ARE EXPECTED.
THROUGH THE AFTERNOON WE'LL SEE THE COLD FRONT DROP SOUTHEASTWARD,
MOVING INTO A MOIST UNSTABLE AIRMASS. SURFACE BASED CAPE EVEN NOW IS
1500-2000 J/KG IN OUR NW THOUGH WE ARE AT THIS POINT SEEING SOMEWHAT
OF A CAP. BY LATE MORNING AS THE CAP ERODES, SURFACE BASED
INSTABILITY RISES AND EXPANDS CWA-WIDE INTO THE 1000-2500 J/KG
RANGE. MID LEVEL LAPSE RATES START OUT STRONG THIS MORNING AT 6.5 TO
7.5 C/KM, BUT BY LATE AFTERNOON WE DO SEE THEM START TO DROP TO 5.5-
6.5 C/KM WHICH IS LESS FAVORABLE IN TERMS OF OUR SEVERE WEATHER
THREAT. THAT BEING SAID, FORCING FROM THE COLD FRONT/MID LEVEL WAVE
COMBINED WITH AMPLE SURFACE INSTABILITY/MOISTURE IS SUFFICIENT TO
KEEP THINGS AT LEAST MARGINALLY SEVERE (ESPECIALLY WITH 0-6KM BULK
SHEAR ON THE ORDER OF 30 TO 45 KNOTS). THE MAIN THREATS WILL BE
DAMAGING WINDS (15% PROB IN SPC OUTLOOKS) AND LARGE HAIL (5% SPC).
IT'S POSSIBLE WE SEE A COMBINATION OF MULTICELL/LINE SEGMENTS AND
POTENTIALLY EVEN A FEW DISCRETE SUPERCELLS. SPC KEEPS THE TORNADO
RISK (2 PERCENT) FURTHER EAST OF OUR AREA FOR NOW, BUT WE ALL KNOW
HOW SUPERCELLS CAN GET SNIPPY IN A HURRY. 0-1KM SHEAR LOOKS TO BE
AROUND 20-25 KNOTS AT POINTS IN THE SOUTH (HRRR HAS SLIGHTLY
HIGHER...). FOR NOW WILL SEE HOW THINGS EVOLVE AND WILL FOCUS
MESSAGING ON WIND/HAIL AS THOSE ARE MUCH MORE LIKELY.
SUNDAY WILL BE DRY FOR MOST AREAS EARLIER IN THE DAY AS OUR COLD
FRONT STALLS OUT SOMEWHERE IN OUR FAR SOUTH/SOUTHWEST CWA OR
POSSIBLY EVEN JUST SOUTH/WEST OF OUR AREA FOR A PERIOD. LATER IN THE
DAY AS WE BUILD SOME INSTABILITY MODELS SUGGEST WE SEE A BRIEF
UPTICK IN THE CONVECTIVE ACTIVITY. KEPT POPS (20-40 PERCENT)
CONFINED TO SOUTHWEST OF A LINE FROM WESTVILLE, IN TO BERNE, IN.
HIGHS WILL BE IN THE MID 80S FOR MOST AREAS. STATIONARY FRONT LIFTS
NORTHEASTWARD AS A WARM FRONT MONDAY INTO TUESDAY MORNING, STEMMING
FROM A LOW OVER SOUTHERN WI/NORTHERN IL. AS THE LOW DRIFTS EASTWARD
INTO LAKE ERIE THROUGH WED AM, WE'LL SEE THE WEAK/DECAYING COLD
FRONT SWING THROUGH AND EVENTUALLY WASH OUT/STALL AS WARM AIR
ADVECTION ENSUES FROM A SEPARATE SYSTEM TO THE WEST (PULLING
MOISTURE FROM THE GULF). THE BOUNDARY LOOKS TO BE ALONG I 80-90 BY
WED AM. TUESDAY HAVE 55-85 PERCENT CHANCES, THEN DIMINISHING TO 25
TO 45 PERCENT WEDNESDAY. HIGHS WILL BE IN THE MID-UPPER 80S ON MON-
TUESDAY, WITH HEAT INDICES CLIMBING INTO THE 90S FOR SOME LOCATIONS.
THE MAIN FOCUS FROM WEDNESDAY ONWARD WILL BE THE HEAT AND HUMIDITY,
WITH HIGH TEMPERATURES BUILDING INTO THE UPPER 80S AND LOW-MID 90S
EACH DAY. OVERNIGHT TEMPERATURES IN THIS PERIOD WILL BE IN THE UPPER
60S AND LOW TO MID 70S, PROVIDING LITTLE RELIEF FROM DAYTIME HEAT.
IT'S HIGHLY PROBABLE WE'LL NEED HEAT ADVISORIES AT SOME POINT IN
THIS PERIOD, WITH HEAT INDICES OF 95-105 DEGREES SEVERAL DAYS IN A
ROW. IF THE FORECAST PANS OUT, WE'D HAVE ABOUT 4 CONSECUTIVE DAYS OF
HEAT ADVISORY CRITERIA, WHICH WOULD BUMP US INTO THE EXTREME HEAT
WARNING HEADLINE CRITERIA. THIS IS ESPECIALLY TRUE GIVEN OVERNIGHT
TEMPS IN THE LOW-MID 70S (AND HUMID). TRICKY ASPECT IS THAT THE HEAT
INDICES OF 100 OR GREATER VARY IN EXACT LOCATION EACH DAY. AT THIS
JUNCTURE, IT WOULD BE WISE TO PREPARE FOR THE HEAT AND PERHAPS
RECONSIDER ANY STRENUOUS OUTDOOR PLANS IF POSSIBLE. THERE WILL BE
DAILY CHANCES (20-30 PERCENT) FOR SHOWERS AND STORMS GIVEN THE HEAT
AND HUMIDITY, AND THE FACT THAT WE'RE ON THE PERIPHERY OF AN UPPER
LEVEL RIDGE THAT GRADUALLY BREAKS DOWN AS A DEEP LOW PRESSURE SYSTEM
LINGERS IN NORTHERN ONTARIO CLOSE TO HUDSON/JAMES BAY. THIS WILL
BRING SEVERAL SHORTWAVES OR SURFACE FRONTS THROUGH OUR AREA.
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
ISSUED AT 1213 PM EDT SAT JUN 6 2026
INHERITED TAFS ARE OVERALL IN GOOD SHAPE FOR THE 18Z CYCLE. KSBN
CONTINUES TO LOOK DRY FOR THE REMAINDER OF DAY; CANNOT
COMPLETELY RULE OUT AN ISOLATED -TSRA PRIOR TO 23Z, YET MOST
GUIDANCE SUGGESTS STORMS DEVELOP SOUTH OF KSBN. THE PROB30 GROUP
CONTINUES AT KFWA AS THERE REMAINS UNCERTAINTY WITH THE
COVERAGE OF STORMS THIS AFTERNOON. SATELLITE WILL BE MONITORED
CLOSELY THESE NEXT FEW HOURS. OTHERWISE, AT BOTH SITES, WIND IS
LIGHT AND VARIABLE FOR A TIME OVERNIGHT BEFORE BECOMING EASTERLY
WITH HIGH PRESSURE SETTING TO OUR NORTH.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...MCD
AVIATION...BROWN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page