That's a little difficult to answer. It's somewhat dependent on maker, material, size.. etc.
Platokidd already referenced OC's tie-down pole kits. Those are a Godsend. You might also consider using deflappers. I have a 15' electric, use the 'max' type deflappers and O.C.'s pole's and very rarely pull my awning in. I've had it out in 35-40mph gusts without any problem, but common sense has to play a role. If you are getting a lot of 'action' in the awning, it's probably a good idea to roll'r up.
My main concern isn't so much about when it is deployed, but unfurling when traveling. I use an awning clamp
which has seemed to work well so far.