Chapter 1 - Non-weapon Proficiencies
Weather Sense Non-weapon Proficiency
This proficiency enables the character to make intelligent guesses about upcoming weather conditions. A successful proficiency check means the character has correctly guessed the general weather conditions in the next six hours. A failed check means the character read the signs wrong and forecast the weather incorrectly. The DM should roll the check secretly. A proficiency check can be made once every six hours. However, for every six hours of observation, the character gains a +1 bonus to his ability score (as he watches the weather change, the character gets a better sense of what is coming). This modifier is cumulative, although sleep or other activity that occupies the attention of the character for a long period negates any accumulated bonus.
Sometimes impending weather conditions are so obvious that no proficiency check is required. It is difficult not to notice the tornado funnel tearing across the plain or the mass of dark clouds on the horizon obviously headed the character's way. In these cases, the player should be able to deduce what is about to happen to his character anyway.