Monsoons Strike Again: Dam Break in the Grand Canyon

While most US citizens think of monsoons as events that happen overseas, there is a definite rainy season in the United States. Known also as the Arizona monsoon or the Mexican monsoon, the North American monsoon can cause a daily deluge of thunderstorms across parts of the Southwest United States. For example, near the Grand Canyon, the Redlands Dam along Cataract Creek broke around 6 a.m. Sunday. Up to 8 inches of rain fell on the region causing the soils to become water-logged and weak. Hundreds of residents and campers were evacuated from the remote Native American town of Supai where about 400 members of the Havasupai tribe live. Supai is located approximately 75 miles west of the South Rim of Grand Canyon National Park. No injuries were reported, but the rains are expected to continue. The American Red Cross Grand Canyon Chapter has released a list of safety tips for dealing with monsoon season in the Grand Canyon region.

While the rainy season in the Southwest is not nearly as strong as the Asian monsoons, the rains can cause flash flooding and gully washers. In 2008, the National Weather Service began to apply a calendar date for the Arizona monsoons from June 15 to September 30.