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Tropical Storm Bill is expected to dump 4 to 8 inches in eastern Texas and Oklahoma

Harris County, Texas, warning: "Bayous and rivers could go out of banks quickly"

CNN  — 

Here comes the rain again.

Still reeling from record rainfall in May, Texas is back in the bull’s-eye as Tropical Storm Bill formed in the northwest Gulf of Mexico on Monday night.

Poised to come ashore Tuesday morning, the system is expected to dump 4 to 8 inches in eastern Texas and Oklahoma.

Western Louisiana and Arkansas are expected to see up to 4 inches of rain.

In Texas, officials sounded the alarm ahead of the storm.

“While high winds and even tornadoes are possible, already wet grounds mean that even a moderate amount of rain will likely cause street flooding,” warned Harris County Emergency Management. “Bayous and rivers could go out of banks quickly creating a serious threat to life and property.” Houston, the state’s most populous city, is in Harris County.

On Monday, coastal Galveston County issued a voluntary evacuation for the Bolivar Peninsula, which sits in the Galveston Bay. Potential rainfall could flood roads on the peninsula, making it harder to leave later or for emergency responders to reach them.

Texas Gov. Greg Abbott also announced on Monday that a special operations center is on alert.

CNN’s Kevin Conlon contributed to this report.