18Z GFS getting the low down to 979MB on the IA/MN border at 21Z Friday. Just southeast of the triple point in east-central Iowa is a pretty screamingly obvious target, square in the left exit region of the mid-level jet. For some reason low-level backing isn't stellar despite the powerhouse low. 18Z NAM, surprisingly, is more progressive and somewhat weaker initially but deepens the low from 21Z to 00Z with better low-level shear, with the target right over MBY into north-central IL.
MKX remaining noncommittal, understandable at this point given the usual uncertainty with warm fronts in this region this time of year.