Story highlights Dallas prepared for thousands displaced by Harvey, mayor says

Convention center in the city can accomodate 5,000 people

(CNN) Dallas opened a mega-shelter at its downtown convention center Tuesday, as the city gears up to help thousands left homeless by Tropical Storm Harvey.

Catastrophic flooding has left large swathes of Houston -- the country's fourth largest city -- underwater. Houston's George R. Brown Convention Center is packed beyond capacity. It sheltered more than 9,000 evacuees Monday night.

"This is going to be the start of what I believe is going to be a long process," Dallas Mayor Mike Rawlings said in a news conference outside the Kay Bailey Hutchison Convention Center on Tuesday.

"Lives have been devastated in Houston. They're fellow Texans, and we're going to help them out," said Rawlings.

Dallas mayor Mike Rawlings said this city is hoping their efforts will show what the nation has learned from Katrina about how to house and help evacuees after hurricanes A post shared by mallory_simon (@mallory_simon) on Aug 29, 2017 at 6:05am PDT

Rawlings said the intention was to create a "little city" with a little bit of everything to help evacuees with what they need. There will be a medical facility with doctors, Walmart is setting up a pharmacy, and there will be places to power electrical devices, he said. He recommended a website, dallashelpforharvey.net , for those looking to donate or volunteer.