windows and water

I have a problem with some windows . We've had a lot of rain recently and when I arrive in the morning, water is soaking the inside sills - one even is pooling ((have to soak it up with towels to get the water out ) .All window sills are slanted to outside. All are well caulked all the way around. Can't see how water is getting in. They are Milguard vinyl . I wrapped plastic around the outside screens in case water was getting blown in.Apparently it's not from that . I don't think it 's condensation. It seems to come in the bottom corners and spread. The windows are sealed all the way around. I even checked the roof above. This is happening with all windows on that side of house. The house was a project when bought but the windows were already in. Any ideas what could be causing this? My husband died recently so I am trying to muddle thru this stuff myself- it is currently not being lived in and I only have a space heater during the day when I am there. thanks........

Well, it takes detective work....flashlight, etc. to find water intrusion. If initial observation doesn't turn up something, it may involve opening some trim or even the drywall.

BUT, it these are sliding windows, there have to be weep holes in the bottom tracks to allow drainage. If they become clogged with paint, dirt, or that stuff you wrapped around the screen, it will back up to the inside. How about some pics?

there are weep holes and it was the first thing I checked- seemed fine. I would hate to tear out drywall. It took me forever to finish it. I am not good with a computer but I'll try photos later . thanks for responding........

There could be problems with the flashing installation (or lack of) at the top of the windows, and it is coming in from around the top, into the window, and showing up at the bottom where gravity takes it. You probably wouldn't be able to see that construction detail unless you took off some of the siding, which could be a major pain.