You came to the right place..My X5 did the exact same thing on a very cold day..Its been single digits here for a prolonged period of time too...First you must see where the oil spray originated from..Meaning where's it coming from? Mine was the valve cover gasket blew...If thats the case then its around 500 bucks to fix at the dealer. Probably less at an indie mechanic shop..But that doesn't really solve the problem..It is just a symptom...I still am going to have to replace the oil seperator which is more pricey job because of the labor involved i believe..Although I am still waiting to hear how much that might be...

The condensation is freezing in your oil lines and that is causing it to back up somewhere..ie. something has to give..Most commonly it is the valve cover gasket that blows first. I sprayed about a quart and a half of oil all over my engine bay before I stopped and had it towed to the dealer..And yes it was smoking profusely I was on 435 South to be exact, right before the Quivira exit...Smoked up the whole freeway......This is a common problem for BMW's unfortunately...Let me know if you need any more help, since we are both in KC..