A "hard get out."?

I have a bit of a leak somewhere on my Windscreen.  I duly parked it "Nose-up" soo that water would run back, away from screen, rather than forward.  After a while I  "clarted it up" with black Silicone Sealer, followed by Capt. Tolley's creeping crack cure.  Which seemed to work - until now, when it's happened again - BUT - to a lesser extent.
       Back to nose-up, until dry weather.
      There was quite a clutter of Cars making life difficult.  When I reverse parked it'd have been no problem and driving out also no problem - BUT - reversing out wasn't fun; thanks to the Estate becoming a thoroughfare while parts of Town Centre is worked on.