My 2009 plus4 does it- I just thought it was because Irish rain was "thicker"!!!!
That reminds me of a comment a builder in Dunghloe Co Donegal came out with after I wished him a good morning and said it's a bit damp this morning. "The clouds are a wee bit low this morning yes" it put a smile on my face thinking about it. That was back in 1972 maybe it is pishing down nowadays.
Back to the thread John has nailed it, if you don't like the damp inside the car don't drive any Morgan in the wet.
2009 4/4 Henrietta 1999 Indigo Blue +8 2009 4/4 Sport Green prev 1993 Connaught Green +8 prev