Editor’s Note (8/30): This story has been updated to reflected current evacuee numbers at Houston’s George R. Brown Convention Center and Dallas’ Kay Bailey Hutchison Convention Center.

With a deadly hurricane bringing unprecedented floodwaters to Texas, convention centers in the state’s two largest cities are taking on an unusual but necessary new role as places of emergency shelter.

By some estimates, Hurricane Harvey, the strongest storm to hit Texas in 50 years, will drop as much as 50 inches of rain on the southeastern part of the state, straining the resources of cities like Galveston and Houston.

In hard-hit Houston, where thousands have been rescued from rising waters since Harvey arrived early Sunday morning, authorities turned the George R. Brown Convention Center into a makeshift shelter. At its peak, the convention center was hosting as many as 10,000 people. On Wednesday, 8,000 people were still there, according to a Facebook post by Tom McCasland, Houston’s interim director for housing and community development.

And while Dallas is largely out of reach of the storm’s worst devastation, the city’s Kay Bailey Hutchison Convention Center was being converted into a megashelter, ready to accommodate as many as 5,000 evacuees. As of Tuesday evening, with the closure of Interstate 45 preventing travel to Dallas, the shelter had taken in only 227 people, though many more are expected once roads are passable, according to the Dallas News.

The convention center was set up like a “mini city,” according to ABC’s Dallas affiliate, WFAA. Charging stations and a Walmart-operated pharmacy area will be available to evacuees.

“When our neighbors need us, we step in and give a helping hand,” the convention center wrote on its Facebook page Monday morning.

While the two facilities combined can hold thousands of people, serving so many evacuees could prove a challenge. In comments to NBC’s Dallas-Fort Worth affiliate, Dallas County Judge Clay Jenkins noted that the demand for shelter far outpaces the supply.

“We have approximately 740,000 people who live in this hurricane watch area of 30 counties. We have a maximum capacity, if we open all shelters—both private and public—in Texas of about 41,000 shelter spaces. So that’s right at 700,000 people who we don’t have shelter space for,” Jenkins said. “So what I’m asking is that if your cousin who is a pain in the neck to you asks to sleep on your couch for a few days, let the cousin sleep on the couch.”

Impact on Events

The Houston convention center is scheduled to host several events in September—and organizers for at least two of them, the Turbomachinery & Pump Symposia and the Insulation Expo USA, posted messages Monday saying they are evaluating whether to reschedule.

At least one association meeting in Houston has already been canceled. The Houston Promotional Products Association plans to reschedule its Hot Stuff Expo, which was to take place Tuesday at NRG Park, the stadium where the Houston Texans play.

“The safety of our members, supplier reps, and NRG employees is of utmost importance,” HPPA stated on its website. “We in Houston know that these hurricanes are often unpredictable and can turn on a dime, which is why we have closely monitored the storm coverage and wanted to gather as much information as possible before canceling. We also understand that you all need time to change or cancel plans for travel.”

The Hutchison Center in Dallas said events scheduled there will continue, including Ambit Energy’s annual Ambition Convention, slated to start Tuesday.

Texas National Guard members help evacuate people caught in the flooding caused by Hurricane Harvey. (Texas National Guard/Flickr)