Monsoon rains can occur from late June through September, bringing flash floods. Be aware of the weather, particularly late afternoon thunderstorms. Avoid travel in creek beds when rain is likely. Don't enter flood waters, the strength of the flow may be stronger than you estimate. Be aware the rain may occur away from you and still create a flash flood that travels for miles down slope. Approaching flood waters make a rumbling sound, similar to a train coming down tracks.