Winter Season In United States May 2026

Due to the country’s vast size and diverse geography, winter conditions can begin as early as October in northern states (e.g., Montana, North Dakota) and persist into April or even May in high-altitude regions (e.g., Rocky Mountains) and northernmost areas like Alaska. The United States experiences some of the most extreme winter weather contrasts in the world, from mild, nearly frost-free winters to brutal subzero Arctic outbreaks.

1. Timing and Duration Astronomically and meteorologically, winter in the Northern Hemisphere runs from the winter solstice (around December 21) to the vernal equinox (around March 20) . However, meteorologists define winter as December, January, and February – typically the coldest three months of the year. winter season in united states