Cold snaps make it more pronounced as the engine block will be that much colder as will the exhaust system, hence glow plugs stay on a tad longer, to help the fuel burn but when starting from stone cold it isn't possible to get a complete burn before the cylinder temp starts to pick up. Mine smokes like a twit at key on then clears (stinks too).
Condensation doesn't really have much to do with it, it takes 10 mins + for an exhaust to get to the temperature to boil water condensate off anyway which is why on cold mornings there will generally be wispy smoke coming out the exhaust for a while before it clears off.
