It's totally possible. What you do is take a double homozygous and breed it to a homozygous. Like Blazing Blizzard x Patternless or Mack Snow x Blazing Blizzard or Patternless Albino. The Mack Snow could get confusing because in all actuallity a Mack Snow is het for Super Snow and since it's co-dom you'll get 50% triple hets and the non Macks would obviously just be double hets.
If you had a male that was Patternless Het Tremper and a female that was Blizzard Het Tremper-
Then the offspring results would be:
25% Het. Patternless, Het. Blizzard,
50% Het. Patternless, Het. Blizzard, Het. Tremper,
25% Het. Patternless, Het. Blizzard, Homozygous Tremper,
So you could have a triple het, though you wouldn't know it from the offspring that were only het for Patternless and Blizzard without proving it out.