255
FXUS63 KIWX 050828
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
328 AM EST THU MAR 5 2026
KEY MESSAGES
- AREAS OF DENSE FOG THIS MORNING, WITH SOME ADDITIONAL PATCHY
DENSE FOG AGAIN TONIGHT.
- SHOWERS AND A FEW THUNDERSTORMS OVERSPREAD THE AREA THIS
MORNING INTO EARLY AFTERNOON. SOME POCKETS OF LOCALIZED
HEAVIER RAINFALL POSSIBLE ALONG AND SOUTH OF US ROUTE 24
TODAY.
- UNSEASONABLY MILD FOR FRIDAY WITH HIGHS FROM UPPER 60S TO MID 70S.
- RENEWED CHANCES OF SHOWERS AND THUNDERSTORMS LATE FRIDAY NIGHT
INTO SATURDAY. A FEW STORMS LATE FRIDAY NIGHT INTO EARLY
SATURDAY COULD PRODUCE MARGINALLY SEVERE HAIL ALONG WITH
LOCALIZED WIND GUSTS IN EXCESS OF 40 MPH.
DISCUSSION
ISSUED AT 327 AM EST THU MAR 5 2026
DENSE FOG CONTINUES TO EXPAND NORTHWARD ACROSS FAR NORTHERN
INDIANA/NORTHWEST OHIO EARLY THIS MORNING, AND SHOULD CONTINUE INTO
SOUTHER LOWER MICHIGAN THE NEXT FEW HOURS. THIS FOG HAS FORMED IN A
WEAK GRADIENT WITH LIGHT EASTERLY FLOW TO THE NORTH OF SFC BOUNDARY
ACROSS CENTRAL INDIANA. NO CHANGES ARE ANTICIPATED TO THE DENSE FOG
ADVISORY ACROSS THE ENTIRE AREA THIS MORNING. THE ADVISORY MAY BE
CANCELLED EARLY FOR SOUTHERN HALF OR THIRD OF THE AREA DUE TO SLIGHT
NORTHWARD PUSH OF LOW LEVEL WARM FRONT AND POCKETS OF HEAVIER
RAINFALL MOVING THROUGH.
IN TERMS OF THE RAINFALL, AN UPPER LEVEL TROUGH WITH CIRCULATION
CENTERED OVER SOUTHWEST IOWA WILL CONTINUE ACROSS THE SOUTHERN
GREAT LAKES THIS MORNING. A 60 KNOT 500 MB JET WILL CONTINUE TO
NOSE ACROSS THE OHIO VALLEY THIS MORNING WITH MODERATE TO STRONG
DOWNSTREAM LOW LEVEL THETA-E ADVECTION MAXIMIZED ALONG AND
SOUTH OF THE US ROUTE 24 CORRIDOR. SOME WEAK ELEVATED CAPES OF
100-200 J/KG ARE NOTED THIS MORNING FOR SLIGHTLY ELEVATED
PARCELS, AND HAVE CONTINUED THE MENTION OF EMBEDDED
THUNDERSTORMS WITH THE RAIN SHIELD MOVING NORTHEAST FROM
SOUTHERN IL/CENTRAL IN. THE BULK OF THE RAINFALL ACROSS NORTHERN
IN/NW OHIO SHOULD OCCUR IN THE 11Z-19Z TIMEFRAME, BUT SOME
ADDITIONAL SCATTERED SHOWERS/ISOLATED STORMS ARE POSSIBLE THIS
AFTERNOON ESPECIALLY ALONG SOUTHERN PERIPHERY OF UPPER LEVEL
COLD CORE ASSOCIATED WITH THE UPPER LEVEL TROUGH. THE BEST
CHANCE OF RAINFALL AMOUNTS ABOVE 0.50" STILL APPEARS TO BE ALONG
AND SOUTH OF THE US ROUTE 24 CORRIDOR THIS MORNING INTO THE
EARLY AFTERNOON HOURS. SOME LOCALIZED PONDING IS POSSIBLE ON
ROADS WITH THE STRONGER CONVECTIVE ELEMENTS. GIVEN PROXIMITY OF
LOW LEVEL BOUNDARY, A FAIRLY SHARP GRADIENT IN MAX TEMPS IS
EXPECTED THIS AFTERNOON RANGING FROM LOW-MID 60S FAR SOUTH TO
THE 45 TO 50 DEGREE RANGE ACROSS THE NORTH.
FOR THIS EVENING, MAINLY DRY CONDITIONS ARE EXPECTED AS LOW LEVEL
THETA-E GRADIENT SLIPS SOUTH OF THE REGION FOR A BRIEF TIME.
MEANWHILE, A DIGGING UPPER LEVEL TROUGH ACROSS THE ROCKIES TONIGHT
WILL INDUCED BROAD DOWNSTREAM SFC PRESSURE FALLS ACROSS THE
PLAINS. THIS WILL RESULT IN QUICK TRANSITION TO WARM/MOIST
ADVECTION AND QUICK NORTHWARD TRANSLATION OF THE LOW LEVEL
THETA-E GRADIENT TO THE SOUTHERN GREAT LAKES BY FRIDAY MORNING.
IN THE MEANTIME TONIGHT, A WEAK GRADIENT AND ABUNDANT LOW LEVEL
MOISTURE NORTH OF SFC BOUNDARY SHOULD INDUCE SOME MORE FOG
DEVELOPMENT.
FRIDAY STILL LOOKS TO FEATURE THE WARMEST DAY OF THE PERIOD
WITH BULK OF THE AREA IN WARM SECTOR. THE ADVECTIVE FORCING
COULD GIVE RISE TO SOME SCATTERED SHOWERS/ISO STORMS MAINLY
ACROSS NW IN INTO SW LOWER MI WHERE A BETTER CHANCE OF SOME
LEAD SMALLER SCALE CONVECTIVELY ENHANCED SHORT WAVE EXISTS.
HOWEVER, IT STILL APPEARS BULK OF THE AREA SHOULD REMAIN DRY.
WARM AND BREEZY CONDITIONS ARE EXPECTED AND GUIDANCE LOW LEVEL
THERMAL PROGS STILL SUPPORT HIGHS APPROACHING OR BREAKING DAILY
RECORDS FOR MARCH 6TH (RECORDS HIGHS OF 72 AND 71 AT FORT WAYNE
AND SOUTH BEND RESPECTIVELY).
THE FRIDAY NIGHT INTO SATURDAY PERIOD WILL FEATURE THE NEXT CHANCE
OF SHOWERS AND THUNDERSTORMS. MULTI-RUN DPROG/DT TRENDS
CONTINUE TO INDICATE A SLOWER EVOLUTION TO ROCKIES UPPER TROUGH
ON FRIDAY. MOST OF FRIDAY EVENING INTO THE EARLY OVERNIGHT
SHOULD BE DRY AS WEAKLY POOLED MOISTURE WITH THE NORTHWARD
RETREATING WARM FRONT SHOULD LIFT NORTH OF THE AREA ALLOWING FOR
POCKET OF SLIGHTLY DRIER LOW LEVEL AIR TO ADVECT IN FROM THE
MID MS VALLEY. GIVEN THE SLOWER EVOLUTION, THE BETTER PRE-
FRONTAL MOISTURE AXIS MAY NOT MOVE INTO NW INDIANA UNTIL AFTER
09Z EARLY SATURDAY MORNING. THIS LATER TIMING MAY TEND TO
DISCOURAGE ISOLATED SEVERE POTENTIAL, ALTHOUGH WITH MODEST MID
LEVEL LAPSE RATES, WEAK SFC/NEAR SFC BASED INSTABILITY IN WARM
SECTOR, AND STRENGTHENING SHEAR PROFILES LATE FRI NIGHT/EARLY
SATURDAY, CANNOT RULE OUT A MARGINALLY SEVERE WIND/HAIL THREAT.
THIS SLOWER EVOLUTION ALSO COULD ALLOW THE FAR EAST TO MAKE
ANOTHER RUN AT A 70 DEGREE HIGH TEMP ON SATURDAY. A LOW
CONFIDENCE MARGINAL SEVERE THREAT COULD MATERIALIZE THROUGH
EARLY-MID AFTERNOON SATURDAY EAST OF I-69 IN ASSOCIATION WITH
PRE-FRONTAL MOISTURE AXIS, BUT THIS IS OF VERY LOW CONFIDENCE.
DEPENDING ON EXTENT OF CLOUD COVER/MIXING IN PRE-FRONTAL
ENVIRONMENT, WINDS MAY BE QUITE STRONG SATURDAY IF DECENT PRE-
FRONTAL WARMING CAN BE REALIZED. IF HIGHER END OF TEMPERATURE
FORECAST VERIFIES, SOME GUSTS INTO THE 30 TO 40 MPH RANGE WOULD
BE POSSIBLE.
AFTER A BRIEF COOL DOWN (BUT STILL WELL ABOVE NORMAL) FOR
SUNDAY, EARLY NEXT WEEK STILL LOOKS MILD WITH HIGHS AROUND 70
ONCE AGAIN. LIKELY TO CATEGORICAL POPS WERE MAINTAINED FROM
BLENDED SOLUTION FOR THIS PERIOD AS MEDIUM RANGE GUIDANCE STILL
POINTS TO COMBINATION OF ACTIVE NORTHERN STREAM AND INGESTION OF
CUT-OFF SOUTHERN STREAM DISTURBANCE ACTING TO SHARPEN LOW LEVEL
BAROCLINICITY FOR WIDESPREAD RAIN SOME TIME IN THE TUESDAY PM
TO LATE WEDNESDAY PERIOD.
AVIATION /06Z TAFS THROUGH 06Z FRIDAY/
ISSUED AT 153 AM EST THU MAR 5 2026
DENSE FOG WAS FORMING AND EXPANDING NORTH OF A WARM FROM THAT WAS
SOUTH OF THE TERMINALS. SHOWERS WERE ALSO DEVELOPING AND SPREADING
NORTH INTO NORTHERN INDIANA ALONG THE UPPER FRONT. LIFR IS
EXPECTED TO PERSIST THROUGH THE ENTIRE TAF PERIOD AS THE FRONT
REMAINS SOUTH OF THE AREA AND AS MILD AND MOIST AIR CONTINUES TO
SPREAD NORTH. AT THE START OF THE TAF PERIOD, THE FRONT WAS SOUTH
OF A LINE FROM LAF TO MIE. THE FRONT WILL GRADUALLY MOVE NORTH,
BUT WILL STILL REMAIN SOUTH OF THE TERMINALS THROUGH THE END OF
THE TAF PERIOD AT 06Z. UNSEASONABLY MILD AND MOIST AIR WILL
CONTINUE OVERRUNNING THE COOL AIR IN THE SECTOR NORTH OF THE
FRONT. THIS PATTERN WILL HELP KEEP A STEADY SUPPLY OF LOW CLOUDS
AND PRECIPITATION, SO HAVE KEPT VERY LOW CEILINGS FROM 003 TO
006 AT BOTH SITES WITH VISIBILITIES DOWN TO 1/2SM AT TIMES.
IWX WATCHES/WARNINGS/ADVISORIES
IN...DENSE FOG ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS MORNING FOR
INZ005>009-012>015-017-018-020-022>027-032>034-103-104-
116-203-204-216.
OH...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR OHZ001-002-
004-005-015-016-024-025.
MI...DENSE FOG ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ078>081-
177-277.
MARINE...DENSE FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LMZ043-
046.
DISCUSSION...MARSILI
AVIATION...SKIPPER
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