685
FXUS63 KIWX 211633
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1233 PM EDT MON SEP 21 2026
KEY MESSAGES
- DRIER WEATHER AHEAD THE NEXT 7 DAYS, THOUGH CANNOT RULE OUT A FEW
POCKETS OF LIGHT SHOWERS AND SPRINKLES TODAY INTO TUESDAY.
- BELOW NORMAL TEMPERATURES THROUGH THE END OF THE WEEK.
- DANGEROUS SWIMMING CONDITIONS ARE EXPECTED ON SOUTHERN LAKE
MICHIGAN BEACHES THROUGH EARLY THIS EVENING.
UPDATE
ISSUED AT 1059 AM EDT MON SEP 21 2026
SPLIT FLOW ACROSS THE CENTRAL/NORTHERN PLAINS HAS LED TO A
DOWNSTREAM LOW AMPLITUDE FLOW ACROSS THE SOUTHERN GREAT
LAKES/OHIO VALLEY. MID/UPPER TROUGH CONTINUES TO SLOWLY NUDGE
EASTWARD AND WILL OVERSPREAD THE EASTERN GREAT LAKES THIS
AFTERNOON. AS THIS OCCURS SOME DRIER MID LEVEL AIR WILL ADVECT
ACROSS THE REGION THIS AFTERNOON INTO THIS EVENING. LOW
AMPLITUDE NATURE TO THE FLOW WILL ONLY FOR ONLY A SMALL
SOUTHWARD SAG ON LOW LEVEL FRONT TODAY WITH A POTENTIAL OF SOME
SCATTERED SHOWERS REDEVELOPING THIS AFTERNOON SOUTHEAST OF US
24, ALTHOUGH ALSO MAY BE MORE IN FORM OF DRIZZLE GIVEN MID LEVEL
DRYING.
STIFF NORTHEAST FLOW HAS LED TO WAVES BUILDING INTO THE 3 TO 5
FOOT CATEGORY AT MICHIGAN CITY THIS MORNING. A HIGH SWIM RISK
HAS BEEN ISSUED FOR NORTHERN LA PORTE COUNTY THROUGH THIS
AFTERNOON, ALTHOUGH IS IT POSSIBLE WAVES APPROACHING 4 FEET
COULD BE EXPERIENCED ACROSS PORTIONS OF SW LOWER MICHIGAN FOR A
BRIEF TIME LATE MORNING/EARLY AFTERNOON.
DISCUSSION
ISSUED AT 237 AM EDT MON SEP 21 2026
OVERALL TREND THROUGH THE WEEK WILL BE FOR BELOW NORMAL TEMPERATURES
AND PRIMARILY DRY CONDITIONS WITHIN LOW LEVEL EAST-NORTHEAST FLOW ON
THE SOUTHERN FRINGES OF AN EXPANSIVE NORTHERN GREAT LAKES HIGH
PRESSURE SYSTEM. STILL CAN'T RULE OUT SPORADIC POCKETS OF LIGHT
SHOWERS OR SPRINKLES TODAY GIVEN LINGERING COLUMN MOISTURE AND
ANOTHER WEAK MID LEVEL DISTURBANCE DRIFTING EAST ATOP THE PRIMARY
FRONTAL ZONE NOW WELL SOUTH OF THE AREA. BEST CHANCES, 20-40%, FOR
MEASURABLE LIGHT RAIN WILL GENERALLY BE SOUTH OF THE US 24 CORRIDOR
TODAY. A MORE PRONOUNCED SHORTWAVE JUST ENTERING THE NORTHERN PLAINS
DOES SHIFT EAST OVER THE AREA TUESDAY INTO TUESDAY NIGHT. CONTINUED
LOW LEVEL DRYING WILL KEEP ANY SHOWER/SPRINKLE ACTIVITY LIGHT AND
ISOLATED/SCATTERED AT BEST DURING THIS TIME, WITH THE BULK OF THE
PERIOD DRY AND COOL.
A MORE NOTABLE INJECTION OF DRY AIR OCCURS MID WEEK THROUGH THE
WEEKEND AS AN UPPER LEVEL BLOCKING PATTERN SETTLES IN WITH THE LOCAL
AREA GENERALLY LOCATED IN A SUBSIDENT REGIME ON THE BACKSIDE OF A
DEVELOPING MID ATLANTIC NEGATIVE HEIGHT ANOMALY. MORE IN THE WAY OF
SUNSHINE AND GRADUAL AIR MASS MODIFICATION SHOULD PUSH HIGHS BACK
INTO THE LOW TO MID 70S BY THIS WEEKEND.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1231 PM EDT MON SEP 21 2026
OVERCAST SKIES PERSIST TODAY AND TONIGHT DUE TO CAA AND GUSTY
NORTHEASTLY WINDS. WINDS WILL CONTINUE TO BE SUSTAINED AROUND 12
TO 15 KTS THROUGH THIS EVENING WITH GUSTS AS HIGH AS 20 TO 25
KTS, ESPECIALLY AT KFWA. WINDS REMAIN ELEVATED OVERNIGHT BEFORE
BECOMING GUSTY AGAIN LATE TOMORROW MORNING. CEILINGS ARE
EXPECTED TO GRADUALLY LIFT OVERNIGHT INTO TOMORROW MORNING; IFR
CEILINGS PREVAIL AT KFWA BEFORE BECOMING MVFR BY MIDDAY
TUESDAY. CLOSER TO LAKE MICHIGAN AT KSBN, CLOUDS ARE EXPECTED TO
DIMINISH WITH VFR CEILINGS THROUGH THE TAF FORECAST PERIOD. DRY
CONDITIONS ARE EXPECTED AREA-WIDE.
IWX WATCHES/WARNINGS/ADVISORIES
IN...BEACH HAZARDS STATEMENT UNTIL 4 PM CDT THIS AFTERNOON FOR
INZ103.
OH...NONE.
MI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ046.
UPDATE...MARSILI
DISCUSSION...STEINWEDEL
AVIATION...JOHNSON
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