In article ,
Dave Cornwell writes:
Or for the youngsters who like online stuff similar here based on
RH:-
http://www.sciencebits.com/SnowProbCalc

(plus a link to the theoretical equations)

Presumably using dry-bulb and dewpoint, or dry-bulb and RH, or dry-bulb
and wet-bulb are all alternative ways of doing what's effectively the
same calculation. (Wet-bulb temperatures seem to have rather gone out of
fashion for some reason. It's surprising, since if the wet-bulb is below
0C you know at once that anything frozen isn't going to melt.)
--
John Hall

"Whenever people agree with me I always feel I must be wrong."
Oscar Wilde