For E and SE of L. Ontario, it looks like Sunday's LES event will be a relatively short/transient event (a few hours?), south of ART.
That said, rates will be stout, based on 3k and RGEM depictions ATT.
Thick DGZ and Omega intersect almost perfectly. (see below) Ratios should be well north of 20:1 with rates, at times, approaching 4"/hr. when near ART.
As the band settles southward through Oswego county Sunday, rates should subside some and then lower substantially as it moves south of the Oswego/Onondaga Co. border.
I see Watertown area (+/- 7mi. North or south) getting 10-14+"...5-10" in Oswego Co. and 2-5" south of there.