America’s 'Springiest' Days

Methodology: To determine the “Springiest” date in each U.S. state, we looked at when spring tends to feel fully established rather than just beginning. The starting point was the spring equinox on March 21, which marks the astronomical arrival of spring. We then compared this with Climate.gov’s map showing the average date of the last spring freeze in each region, indicating when the risk of frost typically passes. Finally, we factored in the period shortly after this point when greenery usually begins to peak and outdoor spaces come back to life, as plants typically need a short stretch of stable, frost-free weather to leaf out. March 2026.