you can take a train into Jasper, but I don't know about Banff...
if you go, you must drive from Banff up to Jasper......178 miles one way and very worth the trip because its constant scenery...
must see's are Lake Louise, and if you can, hike up to the farthest tea house....well worth it and excillerating...
also, Morraine Lake....
Thanks for telling me. That's my kind of weather. 8>)