A Banana Blizzard is a combination of 2 recessive traits: Blizzard and Murphy Patternless. Some people and breeders advertise Yellow Blizzards as Banana Blizzards. These are not true Banana Blizzards. A true Banana Blizzard is a Murphy Patternless crossed with a Blizzard. Test breeding must be done to prove out both traits as it is hard to see both genes being expressed.
Blizzard: recessive Murphy Patternless: recessive