ABC NewsBy KARMA ALLEN and MAX GOLEMBO, ABC News

(NEW YORK) — Residents in Galveston and Port Arthur, Texas, were ordered to evacuate as Hurricane Laura strengthens in the Gulf of Mexico. The storm is forecast to make landfall Wednesday night as a major Category 3 hurricane with winds of up to 115 mph in eastern Texas.

The mandatory evacuation order was signed at 6 a.m. as the storm headed toward Houston. The mandatory evacuations will be ongoing through early Wednesday, island officials said, citing the “uncertainty of the path and the heightened intensity of this storm.”

Officials warned that city services would be suspended at 12 p.m. local time. The state will be staging buses throughout the area for those residents who have signed up for transportation assistance.

“With the uncertainties of this storm and its increasing strength, we need to take all necessary precautions to protect our residents,” Galveston Mayor Craig Brown said. “It’s imperative that you make plans this morning to secure your homes and move you and your family to safety off island.”

He urged residents to secure loose items and leave the island by 12 p.m., adding that it was “urgent that residents heed this mandatory evacuation and leave with all family members and pets.”

Residents in Port Arthur, Texas, located about 110 miles northeast of Galveston, were also under mandatory evacuation orders. The mandate was a “direct result of the imminent dangers” from Laura and Tropical Storm Marco, a separate storm system in the Gulf of Mexico that’s forecast to make landfall on the Southeast Texas coastline mid-day as a tropical depression. It’s expected to produce heavy rainfall and wind gusts up to 30 miles per hour.

City officials in Houston and Harris County urged residents to stay off the roads so people evacuating have access to the freeways. Local officials urged all residents in the storms’ path to fill up their gas tanks and generators now.

“People are going to be evacuated, either from Port Arthur, from Chambers to Galveston County, to the extent that is called for, to allow them to kind of get through on , going into Wednesday,” Houston Mayor Sylvester Turner said in a statement.

He added, “Harvey was a rainy event. This one, for example, would be more of a windy day. We are certainly more prepared than we were three years ago. We learned a lot from Hurricane Harvey but you cannot compare Harvey, with what we are dealing in this particular case.”

Galveston County also issued voluntary evacuation orders for residents on the Bolivar Peninsula, including the unincorporated areas of Port Bolivar, Crystal Beach, High Island and Gilchrist, where inundation models currently show a possible 3 feet to 6 feet of flooding on the Bolivar Peninsula.

The voluntary evacuation could become a mandatory evacuation depending on further weather updates, county officials said.

Laura is now moving through very warm water in the Gulf of Mexico with favorable atmospheric environment for strengthening.

Landfall is expected to occur on late Wednesday night or early Thursday morning with possible storm surge of up to 13 feet in parts of eastern Texas and western Louisiana.

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