Ash was actually noted in-series to exhibit monkey-like athletic ability. He can climb things with ease, jump from branches to branches, even mingle effortlessly into any simian-form Pokemon group!
The not sarcastic question being, *how fast are Ash doing those stunts.* As the 117th episode mentioned 'sudden gust of wind are usual', and Alola was based on Hawaii islands, we can look at the average wind speed on Hawaii to get a rough estimate how fast that wind is blowing-it's 14.4 miles per hour, or 23.17kmph.
That would mean Ash needs to move at HIGHER speed than the hat blown by that wind, which is after converted to smaller unit equals 6.43 meters per second. It's totally possible, given human's average running speed is 45kmph, or 12.5 mps. Even kids has average speed of 8.6 mps.
