May marks a genuine shift toward summer across North America, though the timing depends a lot on how far north or south you look.
National parks and mountain trails begin opening up as snow melts at higher elevations, though some routes stay closed well into the month. The Caribbean and Mexico stay warm and mostly dry, with hurricane season still weeks away. Memorial Day weekend at the very end of the month unofficially kicks off the busier summer travel season across much of the United States. Northern regions warm up more slowly, with pleasant but still cool weather that suits travelers who prefer to avoid the heat of high summer. Cities across the continent also start hosting more outdoor events as the weather turns reliably warmer.
The destinations on our list for North America reflect that same shift, from early summer warmth to the last of spring's cooler days.
