Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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419 FXUS63 KIWX 082235 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 635 PM EDT Tue Sep 8 2026 .KEY MESSAGES... - A warm and more humid airmass will be in place into early Thursday. Cloud cover and precipitation may cause large variations in temperatures Wednesday. - There is a 40% to 60% chance of showers and thunderstorms Wednesday through early Thursday morning. - Breaking waves and currents are expected at southeast Lake Michigan beaches on Thursday. - Somewhat cooler and less humid Friday into Monday. && .DISCUSSION... Issued at 233 PM EDT Tue Sep 8 2026 Low confidence forecast remains through Thursday as models continue to differ on finer details for temps and precip chances, especially Wednesday night. Main cold front (much cooler and less humid air) is located from Minnesota to central NE and is not expected to arrive till Thursday. Much of our weather will hinge on pre-frontal troughs, leftover outflow boundaries and subtle waves resulting in a lot of challenges on coverage, timing and intensity. Area of showers and storms has persisted from central IA into much of WI with only a slow eastward trend. CAMs vary on what will be left of this area as it enters towards 12Z Wed. Regardless of what shape it starts, generally expected some widely sct to sct showers and maybe a few storms to persist in a somewhat unstable atmosphere. The marginal severe threat keys in on the afternoon and evening hours when pockets of clearing could allow for some increased instability to produce some gusty storms. Overall shear is lacking and lapse rates are rather unimpressive so any gusts appear to be isolated at most. Even larger challenges exist where the best instability axis and lingering boundaries setup Wednesday night into early Thursday. Overall trend has been moreso into central IN resulting in a continued southward trend to higher pops. Wasn`t ready to completely eliminate pops but did blend with previous forecast to nudge down. Eventually the main front will arrive Thursday into Thursday night and usher in an end to any precip and much more comfortable conditions. The battle will then continue between the sprawling upper ridge across the SE states and another deeper trough that will attempt to move in next week. For the time being, no major swings in temperatures or high precip chances. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 635 PM EDT Tue Sep 8 2026 Primarily VFR with light southerly winds giving way to southwesterly winds up to near 10 knots on Wednesday. Scattered showers and low chances for an embedded storm do enter the forecast along a pre-frontal trough, best chances (20-40%) later tonight into Wednesday morning at KSBN, and at KFWA Wednesday afternoon. Brief VIS restrictions will be possible in heavier showers, though point chances remain low at this point given weak forcing and unfavorable diurnal timing. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Fisher AVIATION...Steinwedel