Can't get rid of water in pipe

New guy here. Remodeling shower, and I have the main water supply off, and no water coming out of any fixtures. I cut my old diverter out and am going all new the rest of the way up. Problem is, I can't sweat a new fitting on the cold water pipe, due to water in the pipe. I tried sucking the water out but it keeps filling up. I used some plastic tubing to start a siphon, but it has been slowly draining for over an hour now. I'd love to turn my main back on before I go to bed. Any ideas, I realize it's kind of late but thought I'd give it a shot...

Try opening a hose faucet on the outside of the house that is lower than the point you are trying to solder. Depending on how the piping is ran, this might help out.

I have a bunch of fixtures open. The tube is pretty small, so it's draining pretty slow. Tempted to try the bread trick...

Sounds like the main valve isn't holding 100% or the water is siphoning out of the toilet tank. Turn the valve off on the toilet.