Thousands of people fled as the category four hurricane approached, while those who remained behind stocked up on food and water and put their final preparations into place as the storm loomed off the coast, ABC reported.
The hurricane brought 215kph winds and heavy rain. Texans were urged to secure property as Harvey approached.
No casualties have been reported yet.
An estimated 155,000 customers were left without electricity in Corpus Christi and surrounding areas as of 01:00 local time, AEP Texas said.
U.S. President Donald Trump has earlier signed a Disaster Proclamation.
At the request of the Governor of Texas, I have signed the Disaster Proclamation, which unleashes the full force of government help!— Donald J. Trump (@realDonaldTrump) August 26, 2017