A FlyerTalk Posting Legend
Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 102,617
You will need to do pre clearance before the flight to the USA. This usually requires that one check in quite early, IIRC with a T-60 cutoff where sixty minutes puts you at risk of missing the flight.
Can we assume that you won't be checking a bag?