The best time to take a road trip on Route 66 is from late April to early October. Be prepared for remnants of ice and snow during the early spring and thunderstorms in late spring and early summer. During July and August—peak travel months—expect sometimes sweltering temperatures, over-crowded attractions, and higher rates for lodging.
Come late October and into November, you might see snowfall on parts of the route. Winter is considered the off-season, and some places may be closed until spring, so it’s always best to call ahead if you’re venturing out onto Route 66 between late November and early April. Whatever time you travel, expect variations in climate as you’ll be traversing through many different states and terrains.