1. Climate: Streams in wet regions have greater discharge than streams in arid regions.

2. Stream order: First-order streams are often intermittent or have little discharge, even in the wettest of climates.

3. Season: Streams experience peak flow periods that depend on the timing of precipitation or snowmelt. Heavy rainfall can increase stream discharge by several hundred times.

4. Surface permeability: Permeable soil and rock allow water to infiltrate the ground rather than flow over it in a stream channel. Greater permeability reduces surface stream discharge.