Besides the copious driving to, from, and during chases, storm chasing is punctuated with contrasting periods of long waiting and ceaseless action. Downtime can consist of sitting under sun-baked skies for hours, playing pickup sports, evaluating data, or visiting landmarks while awaiting convective initiation. During an inactive pattern, this down time can persist for days. When storms are occurring, there is often little or no time to eat or relieve oneself and finding fuel can cause frustrating delays and detours. Navigating obstacles such as rivers and areas with inadequate road networks is a paramount concern. Only a handful of chasers decide to chase in Dixie Alley, an area of the Southern United States in which trees and road networks heavily obscure the storms and often large tornadoes. The combination of driving and waiting has been likened to "extreme sitting". A "bust" occurs when storms do not fire, sometimes referred to as "severe clear", when storms fire but are missed, when storms fire but are meager, or when storms fire after dusk.