Transcript for Eye of hurricane to pass over area home to nearly half of America's oil refineries

They believe the eye of the storm could pass over port levaca, Texas. Home to nearly half of the U.S.' oil refineries. Rob Marciano is there. Reporter: The wind is picking up, and the water is piling up. This entire area of Texas, very vulnerable to storm surge. Tonight areas south of Houston, scrambling to prep for the northern, more ferocious half of hurricane Harvey. We've got the generator on the back porch, we've got the house all boarded up, we're riding it out. Reporter: Farther west, closer to the expected landfall, a surge of waves and water churning up matagorda bay, already pounding port lavaca. Nearly everyone here evacuated, fresh memories of what happened in 2008, hurricane Ike causing close to $30 billion in damage while taking the lives of 21 Americans. The storm surge from Harvey is what's most concerning in this area. Low pressure lifting the gulf, hurricane winds piling the water up and pushing it ashore, Harvey's wind may be the headline, but it's the storm surge that can be the bigger threat to life and property from a hurricane. The impact here may be felt nationwide. The oil industry is huge here, refineries and petrochemical plants line the coast, many of which are in this storm's path. Gulf refineries produce about 45% of the country's oil and one third of the country's refineries are directly in the hurricane's path, with hundreds of oil rigs drilling in the western gulf. Rob, so many of us who have covered hurricanes know that high tide and low tide plays a role. What are we looking at? Reporter: High tide is at midnight, but the water is going to go where it wants to go. 6 to 12-foot surge expected. It's only slightly less in the north. A huge area of the coastline looking to get some destruction just from the water. Rob, thank you.

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