In daylight you would meter as normal -just remember to expose for the
snow to be white. I would meter the snow and add one stop to the reading
then bracket around that.
   Early evening can get tricky. Do you want just the lights or the lights
and background? Minimal exposure will get you points of light on a dark
field, while givign it more will illuminate areas of teh background. There
is no way to completely accurately predict what it will take so bracket
heavily.
--
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