If you can get the car in from the cold, check the sunroof drains. Should be four, one in each corner. Carefully run some bailing wire through the drain tubes to clear.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.