Houston police chief to Harvey survivors: 'Hunker down, hold tight' Up to 50 inches is expected to fall in the area by Wednesday.

 -- Houston Police Chief Art Acevedo has a message for survivors of Hurricane Harvey who are sill waiting to be rescued: "hunker down, hold tight."

The city's top cop urged patience this morning on ABC News' "Good Morning America" as residents of his city continue to battle through a devastating storm that is expected to drop up to 50 inches of rain, with continued life-threatening flood conditions, in the southeastern region of the lone star state by Wednesday.

"Just hunker down, hold tight -- we hear you, we feel you. Believe me," Acevedo told GMA. "But when you think about just the numbers that we’ve been dealing with, we have to do it safely. We want to make sure that when we get you, we get you out safely and we don’t hurt you or you get hurt during the rescue operation."

Acevedo said that by today, everyone in distress should be rescued.

"Know that we’re coming," Acevedo said. "This morning, sometime today, everybody should be recovered."

Acevedo said that his force has completed about 2,000 rescue missions since the storm began. At least three people have been killed as a result of the storm.

He said the storm has also taken an emotional toll on his force.

"These rescue missions [have] been so heart wrenching for our officers," Acevedo said. "I’ve had officers tear up thinking about the things they’ve seen -- with these little children in the middle of the night -- such fear in four, five feet of water being rescued by our police officers. It’s been a heck of a few days for us."

ABC News' Kelly McCarthy contributed to this report.