Dry Run is a movement gear perk that speeds up your sprint in dry weather. It sits on the Paddock Boots and helps you cover ground on foot when it is not raining.
When the weather is dry, you sprint faster. Rain turns the bonus off until the weather clears.
A decent early boot perk for running around on foot. Perks that work in all weather, like Marathon Runner, are more dependable.
Large Catch Your Breath and Marathon Runner let you sprint longer to make the most of the speed.