LOS ANGELES (REUTERS) - Kim Kardashian and her family on Tuesday (Aug 29) donated a collective US$500,000 (S$675,000) to storm Harvey relief efforts, joining celebrities like Jennifer Lopez, Dwayne Johnson, NFL player J.J. Watt and comedian Kevin Hart who have pledged funds to help the tens of thousands affected by the devastation in Texas.

Kardashian, her sisters Khloe and Kourtney and mom Kris Jenner made the pledges on Twitter, directing their funds to the Red Cross and Salvation Army.

"Houston we are praying for you! My mom, sisters & I will be donating $500,000," the TV reality star tweeted.

Tropical Storm Harvey, which hit land as a hurricane over the weekend, has brought catastrophic flooding to Texas, killing at least 11 people and paralysing Houston.

City officials on Tuesday prepared to shelter up to 19,000 people, with thousands more expected to flee the area.

Ride Along star Hart set the celebrity ball rolling on Monday with a US$50,000 donation and social media challenge that called on stars to match him. Johnson, Lopez and rapper DJ Khaled each have pledged US$25,000.

Houston Texans NFL player Watt launched his own online effort on Sunday with a US$100,000 donation and a video plea. The fund quickly reached US$1 million, and Watt tweeted on Tuesday his goal was now US$4 million.

Houston's most famous export, Beyonce, who has recently moved from New York to Los Angeles, has said she is working on a plan to help her hometown recover.

"Texas, you are in my prayers," the singer posted on her Instagram page.

In statement to the Houston Chronicle on Monday, Beyonce added that she was working closely with her team and her Houston pastor "to implement a plan to help as many as we can."

British band Coldplay, who cancelled a planned show in Houston on Friday because of the impending hurricane, wrote a new song for the city called "Houston #1," which they performed at a concert in Miami on Monday.