Sirius scintillations in a winter's sky

The seasons have shifted and it's back to that time once again, when
you see Sirius shining brilliantly in a cold winter's sky, like a
heavenly diamond suspended above a snow covered landscape and
scintillating through all the reds, greens and violets... 'tis like
the
magic of being in a dream world!!!

Question: in the Austrian Alps at around X-mas time, if you were
staying there for 6 nights, what are the odds that you will
*definitely* get a snowy night with clear skies when you can
experience the above magic?!

I'm planning on going, but would be well disappointed if (a) it didn't
snow, and (b) there wasn't clear skies on any of those six nights to
see the magic of Sirius!

What are my chances?

Abdul Ahad