Warm weather is better for nail growth than cold weather, according to "Nails Magazine." This fact is borne out by researchers, as well.
The findings of a study on high altitude and nail growth, reported in the "Indian Journal of Dermatology, Venereology and Leprology," concluded that a cold climate negatively impacts nail growth. Furthermore, Bruce Robinson, an assistant clinical professor of dermatology at Mt. Sinai Medical Center and Lenox Hill Hospital, also said in a "New York Times" article that the rate of nail growth increased in the summer and decreased in the winter.
A possible reason is the nails' poor blood circulation in the cold weather, according to Dr. Dennis Arnold, founder of the International Pedicure Association.