551 FXUS63 KIWX 042332 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 732 PM EDT Mon Aug 4 2025 .KEY MESSAGES... - Temperatures gradually moderate to above normal this week. By late week and this weekend, very warm and humid conditions return. - There is a slight chance (20%) for isolated/afternoon showers and storms for areas mainly south of US 30 on Tuesday, and along and east of US 31 on Wednesday. && .DISCUSSION... Issued at 206 PM EDT Mon Aug 4 2025 A slow moving mid level trough over the Mid MS Valley will meander eastward through the OH Valley later tonight through Wednesday. This will allow an elevated moisture gradient over the OH Valley to slowly stream north into the local area. Sfc dewpoints will also respond with weak instability developing over southern zones on Tuesday, and over mainly east-southeast zones by peak heating on Wednesday. Overall forcing is weak however with lingering dry easterly flow in the low levels. Continued to cover with a 10-20% type PoP with this feature given these limitations. Seasonably warm and humid otherwise through the middle of the week. Models continue to agree in upper ridging dominating for the second half of the week into the weekend with building heat and humidity, along with mainly dry conditions given a strengthening cap. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 728 PM EDT Mon Aug 4 2025 Another period of quiet aviation weather is expected this forecast valid period. A weak mid/upper level disturbance will continue to drift east across the Ohio Valley tonight into Tuesday. Convection to the south of the area may help to slightly enhanced low level easterly flow across the local area which should keep richer low level moisture confined to the south/southeast of northern Indiana. This should result in limited instability profiles to work with once again on Tuesday with terminals expected to remain dry. Easterly flow persists into Tuesday, although low level height gradient may be weak enough to support a weak lake breeze moving into KSBN vicinity late Tuesday afternoon. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...Air Quality Alert from midnight EDT /11 PM CDT/ tonight to midnight EDT /11 PM CDT/ Tuesday night for INZ005>009- 012>015-017-018-022>027-032>034-103-104-116-203-204-216. OH...None. MI...Air Quality Alert until midnight EDT Tuesday night for MIZ078>081-177-277. MARINE...None. && $$ DISCUSSION...Steinwedel AVIATION...Marsili