Not all lakes are the same here in California. Within less than an hour drive from my house are dozens of lakes from 200 meters wide to over 20 miles wide. Some are surrounded by hills & trees but some are in flat range land. The lakes near the gaps in the mountains that separate the hot Sacramento valley from the cold, windy San Francisco Bay tend to be very windy. On these lakes a 5.0 is your light wind sail. The further into the valley you travel the lighter and gustier the wind. These are the longboard lakes over here.