Weather can be the bane of any athlete, but since air sports have such high stakes, it can easily heighten risk and hasten injury.
Some of the more obvious examples of this include rain and snow storms, which can cause issues with visibility and landing. No matter which air sport you're undertaking, lightning and thunderstorms can be threatening. Storms can result in direct lightning strikes or electronic malfunctions in your craft. Even fog can seriously endanger landing, as the ground is obscured or not visible at all.
There is also the issue of landing. If you're landing on your feet, a slippery surface can make it impossible to do.