145 FXUS63 KIWX 081807 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 207 PM EDT Sun Jun 8 2025 .KEY MESSAGES... - A broken line of showers and storms likely this evening into the early overnight. Gusts to 40 mph and small hail possible with storms this evening, mainly along and west of US-31 in northwest IN. - Additional chances (30-50%) for scattered showers and storms Monday afternoon into early Monday evening. - Trending warmer with highs in the low to mid 80s Wednesday through Friday. - Periodic rain chances return late Thursday through next weekend. && .DISCUSSION... Issued at 206 PM EDT Sun Jun 8 2025 Upper jet streak along the southern side of a broad upper level low digging into the Upper Midwest will drive a sfc cold front through the area tonight with chances for scattered showers/storms. Storms that develop upstream this afternoon will have a decent environment for some stronger convection given strong mid level flow/shear and ~1000 j/kg of MLCAPE pooled near the incoming cold front. This could survive into our far western zones (along/west of US-31) in the 23- 02z timeframe with locally gusty winds and small hail not out of the question. This activity likely weakens and shifts slowly east then for the remainder of the night as it outpaces more favorable ascent and the boundary layer cools. With that said, there could be a late uptick in shower coverage when the boundary slows into east-central IN and northwest OH later tonight into early Monday morning. A subtle convectively aided impulse and nocturnal increase to southwesterly flow in the low levels the possible drivers for this potential coverage increase late. A mid level dry slot does briefly settle in for a time on Monday post-frontal with some sunshine allowing temps to reach well into the 70s for most. Another broken line of convection then follows in for the mid afternoon into early evening hours on Monday as a vigorous vorticity maxima and associated secondary sfc trough pivot through the southern Great Lakes. Moisture will be much more limited by this time with sfc dewpoints down into the low-mid 50s. However, sfc temps warming into the 70s in conjunction with steepening mid level lapse rates on the southern fringes of the cold pocket aloft enough to help generate a few storms with locally gusty winds and small hail once again a possibility. The upper trough responsible for the active weather releases off to the northeast Tuesday into Wednesday allowing a warmer pattern to take shape for the mid to late week periods. As for rain chances, Tuesday and Wednesday appear dry thanks to height rises and a stable/dry air mass. Did continue to hold onto NBM broadbrush low to mid chance PoPs for showers/storms thereafter as a west-to-east oriented frontal boundary sets up somewhere across the Midwest. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1256 PM EDT Sun Jun 8 2025 Weak and even variable surface wind as of this writing due to our proximity between low pressure over central OH and an approaching cold front approaching far western IL. Wind is favored to become southwesterly as the front approaches. Guidance is in good agreement that showers and even thunderstorms can arrive at KSBN prior to sunset. Gradual clearing has allowed for modest instability to develop ahead of the front. Whether or not this reaches KFWA is uncertain, so the TEMPO group there remains. RAP Time height cross sections depict trapped low-level moisture, posing a risk of IFR ceilings, especially at KFWA. In contrast, forecast soundings show a weaker inversion. So, the possibility of IFR ceilings will need to be monitored for the overnight hours. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Steinwedel AVIATION...Brown