Mayor Sylvester Turner told people to stay home. More rain was announced over the next two to three days. Rain gauges in parts of Harris County, which includes most of Houston. Water levels approached 20 inches since late Sunday night. “There is water all over the place, there is flooding all over the place,” the Harris County Flood Control District reported. About 1 million students got the day off, including the Houston Independent School District’s 215,000 students, Texas’ largest public school district. Most colleges and universities also closed. At least two interstates — I-10, the main east-west freeway, and I-45, the major north-south freeway – were under water near downtown. The weather system left warnings and watches through Tuesday morning for Houston, Austin, San Antonio, Dallas, Fort Worth, Tyler-Longview and as far east as Texarkana. George Bush Intercontinental Airport in Houston reported more than 500 flights canceled.