703
FXUS63 KIWX 140517
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
117 AM EDT SUN JUN 14 2026
KEY MESSAGES
- A MARGINAL RISK FOR SEVERE WEATHER REMAINS INTACT FOR TONIGHT,
MAINLY TO THE WEST OF INTERSTATE 69. THE PRIMARY RISK IS FOR
ISOLATED DAMAGING WIND GUSTS AND SOME BRIEF HEAVY DOWNPOURS,
BUT ISOLATED LARGE HAIL IS POSSIBLE. THE MAIN TIMEFRAME OF
THIS ISOLATED SEVERE WEATHER RISK IS ROUGHLY FROM 10 PM EDT
TO 4AM EDT.
- DRY AND COOLER CONDITIONS TO BEGIN NEXT WEEK, TEMPERATURES
MODERATE SOME INTO THE MIDDLE OF THE WEEK BUT THERE WILL BE
INCREASED CHANCES OF SHOWERS AND STORMS FOR THE TUESDAY
THROUGH THURSDAY PERIOD.
- THERE IS A HIGH SWIM RISK FOR SOUTHEAST LAKE MICHIGAN BEACHES
SUNDAY INTO SUNDAY EVENING. LIFE THREATENING WAVES AND
CURRENTS ARE EXPECTED.
DISCUSSION
ISSUED AT 334 PM EDT SAT JUN 13 2026
THE POTENTIAL OF ISOLATED SEVERE STORMS CONTINUES TO BE THE MAIN
SHORT TERM FORECAST CONCERN.
ISOLATED TO SCATTERED SHOWERS AND STORMS HAVE FORMED THIS AFTERNOON
FROM CENTRAL IL INTO PORTIONS OF NORTHEAST ILLINOIS. THESE
SHOWERS HAVE DEVELOPED ALONG THE LEADING EDGE OF AN AMPLIFYING
LOW LEVEL THETA-E RIDGE NOSING TO THE SOUTHERN LAKE MICHIGAN
VICINITY THIS AFTERNOON. CONVECTIVE COVERAGE APPEARS TO BE
ENHANCED ACROSS CENTRAL IL DUE TO SOME CONTRIBUTION OF A
CONVECTIVELY ENHANCED VORT MAX MOVING ACROSS THESE LOCATIONS.
DOWNSTREAM AIRMASS LOCALLY IS MORE STABLE AT THIS TIME, BUT
GRADUAL EASTWARD ADVECTION OF THIS LOW LEVEL HIGHER THETA-E AIR
SHOULD LEAD TO SOME DESTABILIZATION FROM WEST TO EAST. SOME PRE-
FRONTAL CONFLUENCE SHOULD PROVIDE BEST MOISTURE POOLING INTO
THIS EVENING FROM NORTHEAST ILLINOIS INTO SOUTHWEST LOWER
MICHIGAN WHERE AN MLCAPE AXIS OF 1500 J/KG IS EXPECTED TO REACH.
WHILE DIURNAL TIMING OF STORMS IS SOMEWHAT UNFAVORABLE FOR
SEVERE WEATHER, THE SOUTHERN GREAT LAKES DO APPEAR TO BE
SITUATED AT SOUTHERN EXTENT OF STRONGER WESTERLIES WITH RAP
SHORT TERM PROGS SUGGESTING 30 TO 35 KNOTS OF EFFECTIVE SHEAR
EARLY THIS EVENING ACROSS FAR N IN/S LOWER MI. THE POTENTIAL
EXISTS FOR ISOLATED CONVECTION ACROSS THE WEST AS EARLY AS 22
OR 23Z, BUT SHOWERS AND STORMS SHOULD BECOME MORE NUMEROUS LATE
EVENING INTO THE OVERNIGHT, PARTICULARLY ALONG THE PRE-FRONTAL
CONFLUENT AXIS ACROSS THE NORTHWEST WHERE INSTABILITY SHOULD BE
MAXIMIZED. SOME MODEST MID LEVEL LAPSE RATES OF AROUND 7 DEG
C/KM ALSO SHOULD ADVECT INTO THE REGION AND SHOULD ALSO HELP
SUSTAIN SOME MODEST MLCAPE PAST PEAK DIURNAL TIMING. OVERALL
SETUP STILL APPEARS MARGINAL FOR SEVERE STORMS WITH AREAS WEST
OF I-69 STILL APPEARING TO BE IN BEST JUXTAPOSITION OF
SHEAR/INSTABILITY FOR ISOLATED SEVERE THREAT. ISOLATED WIND
APPEARS TO BE PRIMARY THREAT BUT CANNOT RULE OUT A NARROW WINDOW
OF ISOLATED MARGINALLY SEVERE HAIL IN THE 03Z-06Z TIMEFRAME AT
THE LEADING EDGE OF SLIGHTLY STEEPER PLUME OF MID LEVEL LAPSE
RATES. SCATTERED SHOWERS/EMBEDDED STORMS SHOULD CONTINUE INTO
SUNDAY MORNING AS LAGGING MID/UPPER LEVEL TROUGH INTERACTS WITH
LOW/MID LEVEL BAROCLINIC. THE GREATER POTENTIAL OF SEVERE
WEATHER ON SUNDAY STILL APPEARS TO REMAIN FOCUSED EAST OF THE
LOCAL AREA GIVEN FRONTAL PROGRESSION EAST OF THE AREA BY PEAK
DIURNAL TIMING. OTHERWISE, IT WILL BE MUCH COOLER ON SUNDAY WITH
BREEZY CONDITIONS.
QUIET WEATHER IS EXPECTED FOR SUNDAY NIGHT INTO MONDAY AS THE COOLER
AND DRIER AIRMASS SETTLES INTO THE REGION. ANOTHER UPPER LEVEL
SHORT WAVE IS EXPECTED TO DIVE SOUTH FROM SOUTH CENTRAL CANADA
MONDAY NIGHT INTO TUESDAY WITH SOME RENEWED CONVECTIVE FORCING.
HOWEVER, THE OPPORTUNITY FOR ANY SIGNIFICANT MOISTURE TRANSPORT
APPEARS TO BE LIMITED GIVEN THE OVERALL WESTERLY FLOW REGIME.
SHOWERS AND STORMS APPEAR LIKELY ON TUESDAY, ALTHOUGH WITH SOME
MOISTURE LIMITATIONS HAVE SOME CONCERN THAT BLENDED POPS MAY BE
A BIT AGGRESSIVE. BY THE MIDDLE OF THE WEEK, MORE SIGNIFICANT
PACIFIC ENERGY SHOULD TOP WESTERN CONUS RIDGE AND SET UP A
POTENTIAL OF BETTER NORTHWARD SURGE OF LOW LEVEL THETA-GRADIENT
INTO THE LOCAL AREA, WITH PERHAPS A CHANCE OF BETTER
SHOWER/STORM ORGANIZATION HEADING INTO WEDNESDAY/THURSDAY. AS
PREVIOUS FORECAST MENTIONED, STILL A GOOD DEAL OF UNCERTAINTY
HERE WITH WHERE EXACT FRONTAL/WARM FRONTAL PLACEMENT WILL BE FOR
MIDDLE OF WEEK WITH SOME CONVECTIVE MODULATION OF THIS POSITION
POSSIBLE. A BREAK IN SHOWER/STORM CHANCES APPEARS LIKELY FOR
THURSDAY AND FRIDAY, BUT THE POTENTIAL OF ADDITIONAL NW FLOW
WAVES AND LIKELY EXISTENCE OF STRONGER LOW/MID LEVEL THETA-E
SOMEWHERE IN THE VICINITY IN THIS PATTERN ARGUES FOR ADDITIONAL
PRECIP CHANCES BY LATER NEXT WEEKEND.
AVIATION /06Z TAFS THROUGH 06Z MONDAY/
ISSUED AT 106 AM EDT SUN JUN 14 2026
PREDOMINANTLY VFR TO MVFR CONDITIONS AT THE TERMINALS THIS
PERIOD, WITH POTENTIAL FOR DROPS TO IFR IN ANY HEAVIER SHOWERS
OR STORMS. INCOMING COLD FRONT WITH SHOWERS AND STORMS ALONG IT
(STORMS WEAKENING IN INTENSITY AS OF THIS WRITING) WILL CROSS
FROM WEST TO EAST TODAY. AS OF THIS MOMENT A DECENT STORM WAS
DRIFTING EASTWARD TOWARDS THE LAKE MI SHORELINE, AND COULD
IMPACT KSBN WITHIN THE NEXT COUPLE HOURS (IF IT SURVIVES ON THE
NORTH END). ADDITIONAL SHOWERS/STORMS ARE POSSIBLE AS THE FRONT
GETS ON LAND, WITH A WEAKENING TREND THROUGH THE MORNING (MAY
NOT REACH KFWA, BUT IT'S POSSIBLE WE AT LEAST GET RAIN
SHOWERS/MVFR CEILINGS). OTHERWISE, CONVECTION COULD BUILD UP
ONCE AGAIN IN THE EAST TOWARDS THE 14-18Z TIMEFRAME (KFWA), SO
HAVE A PROB30 GROUP FOR THE LATER TIMING. ONCE THE FRONT PASSES
THROUGH EXPECT A WIND SHIFT FROM SW TO NW THROUGH THE DAY, WITH
GUSTS UP TO 25-30KTS POSSIBLE THROUGH MID-LATE AFTERNOON. EXPECT
CLEARING SKIES TOWARDS THE OVERNIGHT HOURS, WITH WINDS
LIGHTENING UP.
IWX WATCHES/WARNINGS/ADVISORIES
IN...BEACH HAZARDS STATEMENT FROM 7 AM CDT THIS MORNING THROUGH
THIS EVENING FOR INZ103.
OH...NONE.
MI...BEACH HAZARDS STATEMENT FROM 8 AM EDT THIS MORNING THROUGH
THIS EVENING FOR MIZ177-277.
MARINE...NONE.
DISCUSSION...MARSILI
AVIATION...MCD
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