Quick and dirty: You are heading into SDF (Louisville Standiford) where the wx is supposed to be IFR/MVFR with the winds out of the northeast. You're coming in from the north. Weather is going to be outstanding until you get close. Approaches in use are going to be ILS or GPS 35L/R. The weather is going to be worse to the south and you really don't want to (#1) or won't (#2) 1) fly past SDF just to come back to it 2) fly into deteriorating weather with embedded TS awaiting you Would you request a GPS approach to 17L with a circle to land on 35R or a contact approach and scud (but not really scud) run the last few miles in? What are the chances they grant either of them to you?