By the use of sand and blown spittle, the caster creates a tiny moaning wind that sounds only in his or her ear. Its steady tone rises or falls if the caster turns aside (to the right or left, respectively) of a chosen direction. Returning to the proper course restores the proper wind hum.
This spell is most often used at night or in blinding sandstorms. It allows the caster to travel in an unerring, pre-chosen direction but cannot guide along a non-straight route, or find features (it can point "northwest," but not "to the blue dragon's cave"). Casting another spell does not end a wind compass.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the duration increases by one hour for each slot level above 1st.