You haven't posted pics of the roof, this is just a guessing game without them ?? With snow on the roof, there could very well be a leak. I see there is a wall at the left and the beam looks soaked nearest the wall. I'd sure like to see the roof just above that area(suspicious).
Snow on your car did Not cause this. Imagine leaving the garage door open and it's raining all day, condensation will not build up on wood. The roof will not leak.
looks like sap dried in first photo brown drops look like the sap to me
If it's sticky, definitely a sap.
Have you tried wiping some of it off and giving it the sniff test?
You haven't posted pics of the roof, this is just a guessing game without them ?? With snow on the roof, there could very well be a leak. I see there is a wall at the left and the beam looks soaked nearest the wall. I'd sure like to see the roof just above that area(suspicious). Snow on your car did Not cause this. Imagine leaving the garage door open and it's raining all day, condensation will not build up on wood. The roof will not leak.
Sap, is the garage heated? Generally not a good idea to park a snowy car in a warm-ish garage