State officials have asked Austin to prepare to house as many as 7,000 evacuees from Hurricane Harvey, Mayor Steve Adler confirmed Monday, though city officials are still determining how many they’re prepared to take.

No matter the ultimate number, "company’s coming," Adler said.

Adler called an emergency City Council meeting for Tuesday morning to discuss Austin’s Harvey response. Council meetings typically require 72 hours of public notification but, in emergency situations, they can be called more quickly.

Austin so far has between 500 and 700 evacuees — a number that has been fluctuating as people come and go — split between four shelters.

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Delco Center, the only shelter available to the general public on a walk-in basis, had 174 people as of Monday afternoon. The Burger Center, a shelter for people rescued from dire situations, had 170. LBJ High School, which is housing evacuees from a Victoria shelter of last resort, had 205. Four people with serious medical conditions were being sheltered at the University of Texas’ J.J. Pickle Research Campus, so as not to take up space in local hospitals, officials said.

The 205 people at LBJ were among about 650 who were expected to arrive from Victoria. Some of those people were trapped in buses overnight after flood waters trapped them on a highway en route to Austin.

"Just getting from Victoria to here was a daunting task," said Juan Ortiz, Austin’s director of homeland security and emergency management.

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The city is preparing Reagan High School and Lanier High School as possible shelter sites to open next. Numbers of evacuees coming to Austin are expected to rise quickly as roadways from the coast become more passable. And some evacuees are headed to other Central Texas shelters, such as one in Smithville.

In addition to taking in evacuees, Austin has sent 26 firefighters to Houston, plus 12 boat squad members, 18 medics, four police officers, four helicopter technicians and one water team manager, Adler said. He expects to send more police officers in the coming days.

Here at home, "when company comes, everybody has chores," Adler said.

He urged Austinites to: Find volunteer opportunities at GivePulse.com; donate money to the Central Texas Food Bank (not cans of food, since evacuees don’t have kitchens); donate blood, since facilities in Houston can’t collect such donations now; donate pet supplies to Austin Pets Alive; donate diapers via AustinDiapers.org; donate household items to Austin Disaster Relief Network or give money to the Red Cross.

"We were spared the worst here in Austin," Adler said. "We will help…with a spirit, with an exuberance and with a helping hand, exactly as we would want extended to us."

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Council Member Sabino "Pio" Renteria, in Spanish, urged Houstonians without electricity to come to Austin, rather than prop open their windows and run the risk of catching mosquito-borne illnesses. Mexican Consul General Carlos González Gutiérrez said consulates would be visiting shelters all over Texas to offer help to Mexican citizens. No one is checking immigration papers at shelters, but the consulates will help repatriate Mexicans who wish to return to Mexico, he said.

Travis County Commissioner Jeff Travillion urged patience.

"We are just at the tip of the iceberg. This is going to be one of the worst disasters in Texas history, maybe in American history," he said. "There are going to be difficult days ahead and this is going to take a long time."