There are multiple factors that cause the water level in the Narrows to increase. These factors can include recent local precipitation, recent upstream precipitation, and sustained spring snowmelt. The National Park monitors these specific factors and how they relate to the water level increases in order to establish hiking restrictions.
Below are the three hiking restrictions and how they can effect your trip into the Narrows.
1. Recent Precipitation:
*Even though the hike is immediately open after the water level falls below the closure level it is not always advisable to enter the river immediately.
2. Sustained Spring Snowmelt:
3. Flash Flood Warning
*Recent Precipitaion rule above (1) may keep the hike closed beyond the 2 hours in this case.