Expires:No;;328818 FXUS63 KIWX 170532 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 132 AM EDT Mon Aug 17 2026 .KEY MESSAGES... - Dry Monday and Tuesday with highs in the upper 70s. - The next chances for rain and storms arrive Tuesday night into Wednesday. At this time, the severe weather and flooding risks are very low. && .UPDATE... Issued at 820 PM EDT Sun Aug 16 2026 Active series of mid/upper level trough passages continues this evening. Much of the local area appears to be situated between stronger mid level forcing this evening, but next mid level trough across northern Illinois has been associated with some renewed convective activity this evening across northeast Illinois. A low level cold front will continue approaching the southern Great Lakes region this evening, with an axis of 2000 J/kg of MLCAPEs preceding it along a 2+ inch PWAT axis from west central Illinois into extreme northwest Indiana. These scattered showers and storms across northeast Illinois should shift eastward across northern Indiana through the remainder of the evening and into early overnight hours as the associated cold front shifts south. Deep layer and effective shear is on the marginal side, but given magnitude of instability and high PWAT areas, a few precip loaded cores could produce localized wind gusts in excess of 35 mph through the early overnight. Some brief heavy downpours are possible, but these showers should be transient and not lead to significant hydro issues. Some minor tweaks to grids have been made to account for slightly higher evening PoPs across the west/southwest/south central portions of the area, but overall spirit of previous forecast with timing and location of PoPs have been left intact. && .DISCUSSION... Issued at 101 PM EDT Sun Aug 16 2026 While satellite and radar trends shows diminishing showers early this afternoon, widely scattered showers and storms are expected to redevelop this afternoon and evening, pivoting around the axis of an area of low pressure centered over Lower Michigan. While I can't completely rule out the chances for a strong to severe storm this afternoon and evening south of US 24, confidence is very low. Moderately instability is favorable for thunderstorm development, but shear and lapse rates are poor. This will likely end up being a similar scenario to yesterday where clusters of storms may produce brief gusty winds but not reach severe thresholds. CAMs show one final round of scattered showers and storms this evening into tonight developing over northwest Indiana with a weak trailing cold front, but rain and storm chances will come to an end by daybreak Monday. Clouds are expected to linger overnight and clearing will commence behind the frontal passage. There is high confidence that our active weather pattern finally comes to an end! Monday and Tuesday will be dry as an area of high pressure builds into and across the Great Lakes. Temperatures will be seasonable with highs in the upper 70s to near 80 degrees. Dewpoints on Monday and Tuesday during peak diurnal heating hours will only be in the low to mid 60s, which will feel much more refreshing than our past week of low to mid 70s dewpoints! As troughing builds over the eastern US and an upper level ridge builds over the western US, another chance for rain and storms comes Tuesday night into Wednesday as a cold front slides from northwest to southeast through our forecast area. As of now the risks for flooding and severe weather are low, but I would not be surprised if our forecast area is added into future SPC outlooks as Wednesday gets closer. Particularly, along and south of US 30 may be at risk for isolated damaging wind gusts Wednesday as the timing of the frontal passage coincides with peak diurnal heating, although confidence is low at this time. High pressure then builds into the Great Lakes and Midwest regions again by the end of the week into next weekend. Temperatures remain near to just slightly below normal with highs in the upper 70s to near 80 degrees through the end of the week. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 132 AM EDT Mon Aug 17 2026 Weak cold front continues to slowly cross the area this morning. Showers and storms remain possible at KFWA through the late morning but coverage will be very limited given poor moisture and forcing. Will therefore hold off on mentioning anything in the TAF. MVFR ceilings likely (especially at KFWA) this morning given some CAA and residual boundary layer moisture. Return to VFR by the afternoon with clearing skies and light winds to end the period. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ UPDATE...Marsili DISCUSSION...Johnson AVIATION...AGD