Rain leak into 2003 VW Jetta

[jettagirl]

We have just started getting large amounts of water after a heavy rain on the floor wells of our Jetta. It is not coming up from the underside, as the car was parked all week. I see no drips; the only irregularity is a little rubber valve visible when the front doors are open just under the upper door hinge that opens when it is squeezed and about i/2 cup (?) of water came out. Can’t see where this valve is connected to.