The top three qualify automatically and the fourth-placed side go into a playoff with a team from the Asian conference.
A win would guarantee the U.S. a place at next year's finals in Russia and a point could be enough against a Trinidad & Tobago team already out of the running for a World Cup spot.
Mexico and Costa Rica have already qualified.
The playing surface in Couva was heavy after torrential rain in the Caribbean and the U.S. were not able to train properly on Monday. Pictures showed the area around the pitch looking more like a moat than an athletics track.
Arena, though, said conditions were the same for both sides and was optimistic the U.S. would get the result they need to qualify for their eighth World Cup in succession.
"The field conditions definitely change the way the game is going to look... it'll be slower, a little bit sloppy, but we have to adapt," he told reporters.
"Tomorrow is going to be challenging... it's going to look a heck of a lot different than the game we just played," he added after the U.S. beat Panama 4-0 in Orlando on Friday.
(Reporting by Andrew Downie; Editing by Ken Ferris)
