Congratulations on your new and first of the year inflo. The high temp here at my house is 37f out side right now. Out of all my plumeria (15) they are in the greenhouse and have dropped very few leaves. But I am quite sure it will be quite a while before a inflow appears here.
Donna S is one of those plumeria that continues to bloom all season long, and often retains an inflorescence through the dormant season, only to revitalize it again in spring. Here it is blooming today: