Tucson's Welcome Home Veterans Parade is tomorrow, Saturday, March 31 beginning at 10:30 a.m. in downtown Tucson. Full details are here on the Downtown Tucson site (which might want to consider updating the photo on that page unless they want this to be a really weird parade). There's also a Facebook page for the event.
ADDING: Sorry for the link dump, but the official site for the event appears to be ThankYouAZVets.org. They've got a clearer map on that site and other useful materials.