247
FXUS63 KIWX 160951
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
551 AM EDT THU APR 16 2026
KEY MESSAGES
- MORNING SHOWERS WILL GRADUALLY DISSIPATE TOWARD MID MORNING.
- ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO DEVELOP AGAIN TODAY PARTICULARLY ACROSS NORTHEAST INDIANA,
SOUTH CENTRAL LOWER MICHIGAN, AND FAR NORTHWEST OHIO.
WIDESPREAD SEVERE WEATHER IS NOT EXPECTED, BUT A FEW SHOWERS
AND STORMS MAY PRODUCE WIND GUSTS TO 50 MPH AND SMALL HAIL
THIS AFTERNOON.
- MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED LATE FRIDAY NIGHT
INTO SATURDAY. THERE IS SOME STRONG TO SEVERE WIND GUSTS WITH
THESE THUNDERSTORMS LATE FRIDAY NIGHT THROUGH MID AFTERNOON
SATURDAY.
- MUCH COOLER FOR SUNDAY BEHIND A COLD FRONT, BUT TEMPERATURES
MODERATE EARLY NEXT WEEK.
DISCUSSION
ISSUED AT 352 AM EDT THU APR 16 2026
A 55 TO 65 KNOT UPPER SPEED MAX PROGRESSING THROUGH SOUTHWEST UPPER
FLOW AND STRONG LOW LEVEL MOISTURE TRANSPORT IS AIDING IN
MULTIPLE CLUSTERS OF SHOWERS AND ISOLATED THUNDERSTORMS ACROSS
THE AREA. LOW LEVEL CIN HAS DEVELOPED LOCALLY WHICH SHOULD TEND
TO DECREASE THIS CONVECTION OVER NEXT FEW HOURS. SOME LINGERING
OUTFLOW HAS RESULTED IN SOME ISOLATED GUSTS OVER 40 MPH, AND
THIS MAY CONTINUE TO BE THE CASE THROUGH 10Z. WHILE ADDITIONAL
PRECIPITATION THIS MORNING MAY ONLY BE IN THE QUARTER TO HALF
INCH RANGE WITH THE HEAVIER POCKETS OF RAINFALL, THIS ADDED RAIN
IN AREAS WHICH HAVE EXPERIENCED HEAVY MULTI-DAY RAIN AMOUNTS
COULD LEAD TO SOME MINOR FLOODING. CURRENT EXPECTATION IS THAT
FLOOD WATCH WILL BE ALLOWED TO EXPIRE AT 12Z.
FOR TODAY, THE MORE AMPLIFIED UPPER LEVEL TROUGH WILL LIFT NORTHEAST
TO SOUTHEAST ONTARIO AS IT ENCOUNTERS AND DAMPENS THE STUBBORN MEAN
EASTERN CONUS UPPER RIDGE. THIS TRACK WILL MAKE FOR SLOW SOUTHEAST
PROGRESS TO LAGGING LOW LEVEL FRONT THIS AFTERNOON. DEEPER MOISTURE
AXIS SHOULD BE SHIFTING EAST OF THE LOCAL AREA THIS MORNING, BUT
COOLING ALOFT WITH THE UPPER LEVEL LOW TRACK SHOULD ALLOW FOR SOME
WEAK TO MODERATE SFC BASED INSTABILITY TO DEVELOP THIS
AFTERNOON (500-1200 J/KG). THE TRACK OF MID/UPPER LEVEL
REFLECTION WILL RESULT IN GRADUALLY WANING DEEP LAYER SHEAR
PROFILES TODAY, AND THUS NOT A GREAT CO-LOCATION OF
INSTABILITY/SHEAR PARAMETERS. AN ISOLATED STRONG TO SEVERE STORM
CANNOT BE COMPLETED RULED OUT ESPECIALLY IN A BRIEF WINDOW
DURING MID-LATE AFTERNOON CLOSER TO THE UPPER LEVEL SYSTEM WHERE
MID LEVEL LAPSE RATES ARE MAXIMIZED ACROSS NE IN/SC LOWER
MI/FAR NW OHIO, BUT OVERALL SEVERE THREAT TODAY IS SUBSTANTIALLY
LOWER THAN PREVIOUS FEW DAYS.
WITH ONLY A PARTIAL DAMPENING OF THE EASTERN CONUS RIDGING TODAY,
ASSOCIATED SFC BOUNDARY IS NOT EXPECTED TO MAKE SIGNIFICANT
SOUTHWARD PROGRESS TONIGHT AND WILL LIKELY STALL ACROSS NORTHERN
IN/NORTHWEST OH TONIGHT. WEAK FLOW IN VICINITY OF THIS TROUGH,
PARTIAL CLEARING AND LIKELY GOOD NEAR SFC MOISTURE LINGERING
BENEATH LOW LEVEL INVERSION SUGGEST POTENTIAL OF FOG FORMATION
TONIGHT.
MID LEVEL RIDGING QUICKLY AMPLIFIES THURSDAY NIGHT INTO FRIDAY
DOWNSTREAM OF A MORE SIGNIFICANT UPPER LEVEL TROUGH THAT WILL DIG
ACROSS THE ROCKIES ON FRIDAY. STRONG LOW LEVEL MOISTURE TRANSPORT
WILL BE CONFINED WEST OF THE LOCAL AREA FROM SOUTHERN PLAINS INTO
EASTERN IOWA ON FRIDAY WHICH IS WHERE CONVECTIVE INITIATION IS
EXPECTED. PROGRESSION OF THIS LONGWAVE FEATURE WILL INCREASE
CONVECTIVE CHANCES LOCALLY ESPECIALLY AFTER 06Z FRIDAY NIGHT.
UPSTREAM CONVECTIVE LINE SHOULD TEND TO OUTRUN BETTER INSTABILITY AS
IT REACHES WESTERN GREAT LAKES OVERNIGHT FRIDAY NIGHT, BUT POTENTIAL
EXISTS THAT SOME SEVERE WIND POTENTIAL COULD BE MAINTAINED INTO
WESTERN PORTIONS OF THE FORECAST AREA OVERNIGHT. STRONG BACKGROUND
WIND FIELDS SHOULD ALSO YIELD STRONG WESTERLY 0-3KM LINE NORMAL
SHEAR VECTORS WHICH COULD INDUCE SOME QLCS PROCESSES. FAR SOUTHEAST
PORTIONS OF THE FORECAST REMAIN IN SWODY3 MARGINAL RISK OUTLOOK,
WITH OVERALL TREND TO FAST FRONTAL PROGRESSION LIKELY LIMITING
SEVERE RISK LOCALLY FOR SATURDAY AFTERNOON.
SUNDAY AND MONDAY WILL FEATURE BELOW NORMAL TEMPS BEHIND THE
ASSOCIATED SATURDAY COLD FRONT BUT MID LEVEL HEIGHTS SHOULD RECOVER
LATE MONDAY IN ADVANCE OF A MORE BROAD SOUTH CENTRAL CANADIAN UPPER
TROUGH. A COOL FRONTAL BOUNDARY WITH THIS FEATURE WILL LIKELY GRAZE
SOUTHERN GREAT LAKES REGION FOR MIDDLE OF NEXT WEEK. IT DOES APPEAR
AS THOUGH WE COULD BE HEADED TO A MORE SEASONABLE TEMPERATURE
PATTERN NEXT WEEK WITH INDICATIONS IN MEDIUM RANGE GUIDANCE OF A
MORE STABLE LONGWAVE PATTERN DEVELOPING OF WESTERN CONUS TROUGH,
CENTRAL CONUS RIDGE, AND EASTERN CONUS TROUGH. THIS WOULD RESULT IN
MORE LIMITED DAY TO DAY THERMAL ADVECTIONS AND AT LEAST SOME BREAK
FROM THE ACTIVE RECENT SEVERE WEATHER PATTERN.
AVIATION /06Z TAFS THROUGH 06Z FRIDAY/
ISSUED AT 550 AM EDT THU APR 16 2026
A 60-70 KNOT UPPER SPEED MAX PROGRESSING THROUGH SOUTHWEST UPPER
FLOW AND LOW LEVEL MOISTURE TRANSPORT HAVE HELPED SUSTAIN
SHOWERS ACROSS NORTHERN INDIANA THIS MORNING. OVER THE NEXT FEW
HOURS BETTER MOISTURE TRANSPORT AND DEEPER MOISTURE PROFILES
WILL SHIFT EAST OF THE AREA WITH AN ACCOMPANYING DECREASE IN
SHOWER COVERAGE. THE GREATER COVERAGE OF ADDITIONAL
SHOWERS/ISOLATED THUNDERSTORMS TODAY IS EXPECTED ACROSS FAR
NORTHERN/NORTHEAST INDIANA AS AN UPPER LEVEL TROUGH SHIFTS
ACROSS THE GREAT LAKES. STEEPER MID LEVEL LAPSE RATES WITH THIS
FEATURE SHOULD RESULT IN SCATTERED SHOWERS/ISOLATED STORMS THIS
AFTERNOON. WITH LOW LEVEL MOISTURE PROFILES NOT AS IMPRESSIVE
TODAY, COVERAGE SHOULD BE MORE LIMITED AND WILL LIMIT SHOWER
MENTION TO PROB30 THIS AFTERNOON. AN ISOLATED THUNDERSTORM IS
POSSIBLE, BUT CONFIDENCE IS TOO FOR TAF INCLUSION GIVEN MORE
LIMITED INSTABILITY. CIG FORECAST IS OF LOW CONFIDENCE TO BEGIN
THIS PERIOD. PROXIMITY OF LOW LEVEL BOUNDARY TO LAKE MICHIGAN
LEADS TO COME CONCERN FOR MVFR OR IFR CIGS EARLY THIS MORNING
BEFORE BETTER LOW LEVEL MIXING OCCURS. DETERIORATING AVIATION
CONDITIONS ARE POSSIBLE TONIGHT AS SFC TROUGH SHOULD SINK
ACROSS FAR NORTHERN INDIANA WITH GREATER FOG POTENTIAL LATE THIS
PERIOD GIVEN WEAKENING WINDS, PARTIAL CLEARING, LINGERING LOW
LEVEL MOISTURE TRAPPED BENEATH THE INVERSION.
IWX WATCHES/WARNINGS/ADVISORIES
IN...FLOOD WATCH UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING FOR
INZ005>009-012>015-017-018-020-022>027-032>034-103-104-
116-203-204-216.
OH...FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR OHZ001-002-004-005-
015-016-024-025.
MI...FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR MIZ078>081-177-277.
MARINE...NONE.
DISCUSSION...MARSILI
AVIATION...MARSILI
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