Monsoon weather is causing flash flooding in southern Utah. Forecasters say over an inch of rain fell in one hour at Zion National Park on Tuesday, causing flash flooding that sent mud and debris flowing onto Route 9, and closing the highway. The park remains open, but forecasters warn that more flash flooding is possible. AccuWeather says more thunderstorm activity is expected across the Southwest this week, and that downpours in the desert region could cause dry creek beds to quickly overflow. Crews are currently working to clear the mud and debris from the roadways in the park. The rain even put a search and rescue mission on pause, but officials were able to resume that evening. The Springdale area saw flooded structures and some cars being lifted and moved by water, but there were no reports of any injuries and no evacuations were issued.