A normal retailer ticket bought during a US visit can end up back in Canada before the draw. Then you have storage, signature, claim location and tax questions all mixed together. What should a visiting player check with the selling state before leaving?
Before leaving the selling state, photograph the front and back, keep the original flat and dry, record the retailer and draw date, and read the issuing lottery's signing instruction. Store checked and unchecked tickets separately. A photograph is a record, not a replacement for the original.
Also save the selling lottery's claim page and deadline. Powerball requires the prize to be claimed in the jurisdiction where the ticket was bought, so crossing into Canada does not move the claim. For a substantial prize, contact that lottery before returning and obtain US-Canada tax advice before making travel or payment arrangements.