The later at night, the more odds of you standing out for stopping in the middle. Even if the barrier's climbable and there aren't any protective fences, that still doesn't make it easier to get over SI and actually doing the deed. I mentioned the hikers and kayakers because there have been multiple instances of people dying due to someone falling on them from jumping. Now, I'm not sure what the odds might be of anyone hiking or kayaking at night, but with visibility being worse at night, I personally wouldn't want to take that risk. The only way I'd feel a little more okay is if you can scout the exact spot where you'll be jumping from and where you'll end up in the water, but that might prove to be a little difficult if you're seen stopping in the middle of a busy bridge in broad daylight. There's a catwalk underneath I believe, but I'm not sure if it's accessible or not.