Phoenix , Arizona, the USA was shaken by a big sandstorm recently. It was a huge dust storm that struck Phoenix a little after 7:00 pm local time. Arizona has sandstorms particularly during the monsoon(  )season which usually starts from mid-June until the end of September. However, this was so far the biggest. The cloud of dust turned day into night. Some trees were downed, gardens were destroyed and it knocked out power for thousands of local people along the area, but luckily no death happened. A number of the people's pools became dirty with dust. People who lived in Phoenix for more than 40 years said that this was the first time they had experienced this huge dust storm. It could greatly influence people's health. The big dust cloud started in Tucson traveling north across the desert. The huge storm ran up to 60 miles per hour. It was more than 100 miles wide and a mile high. Besides Phoenix and near cities ,the storm also reached Yuma area in southwestern and far western Arizona. It reduced the visibility (  ) in these areas, putting off the flights at Phoenix Sky Harbor International Airport. The storm only takes place in Arizona, the Sahara Desert and areas of the Middle East, because of the dry environment and large amounts of sand. Because of the serious shortage of rain, a wall of there's a large possibility that the water is polluted because of the storm. What does the passage mainly talk about?
Sandstorms do a great deal of harm to people We must do something to prevent sandstorms. .Phoenix , Arizona in the US experienced a huge sandstorm. Phoenix, Arizona in the us has more sandstorms.