Hurricane Harvey: Sheer scale of disaster remains to be seen

The fiercest hurricane to strike the US in more than a decade has left at least one person dead and countless others homeless.

Hurricane Harvey has now been downgraded to a tropical storm, but the latest pictures from NASA show it spreading over Texas, bringing what could be life-threatening floods.

The hurricane hit hard and fast, making for a nerve-wracking night in Texas.

Unforgiving winds of more than 200km/h lashed the coastline, flattening buildings and leaving a trail of debris.

"We heard this noise like a freight train and all of a sudden our ears started to pop, and it almost felt like all the air in our home was sucked out and then it was just thrown right back in," Rockport resident Karl Hattman told local media.

Hurricane Harvey hits Rockport, Texas
A man walks through floods waters and onto the main road in Rockport. Photo credit: Reuters

Winds whipped up flames caused by falling power lines. One high school in Rockport was ripped to pieces, and at least 10 people were injured when the roof of a rest home collapsed.

Hundreds of people staying at a hotel were evacuated as it blew apart.

The strength of the storm has made it difficult for emergency services to respond to calls. 

It's still unclear just how many homes are now uninhabitable, but the scale of destruction is huge.

"We went upstairs and looked out the window and down the road here. It was just a sheer wall of water like 100mi/h. It was just crazy," resident Tim Freiburger said.

Hurricane Harvey hits Rockport, Texas
Barbara Koster stands on her front door as she surveys her property. Photo credit: Reuters

It was the most powerful hurricane to strike the US in more than a decade, but the worst is far from over.

While Harvey's been downgraded to a tropical storm, it's now moving very slowly - meaning it will hang over Texas for much of the week, bringing extensive rainfall.

Authorities are now warning of catastrophic flooding.

"Don't risk your life. Still the most important thing that all Texans can do that are affected by the storm is to put your life, and the protection of your life, first and foremost," Texas Governor Greg Abbot said.

Despite the winds having died down, Texans can't be complacent. The greatest danger still lies ahead.