Alberto, which is bringing strong winds, heavy rainfall and some flooding along the coasts of Texas and Mexico, is expected to make landfall in northern Mexico on Thursday.

“The heavy rainfall and the water, as usual, is the biggest story in tropical storms,” said Michael Brennan, director of the National Oceanic and Atmospheric Administration’s National Hurricane Center.

Alberto was located 185 miles (about 300 kilometers) east of Tampico, Mexico and 295 miles (about 480 kilometers) south-southeast of Brownsville, Texas. It had top sustained winds of 40 mph (65 kph), according to the National Hurricane Center in Miami. A tropical storm is defined by sustained winds of between 39 and 73 mph (62 and 117 kph), and above that the system becomes a hurricane.

Brennan said that winds could get up to 45 mph (72 kph) to 50 mph (80 kph) before the storm makes landfall.

As much as 5 inches (13 centimeters) to 10 inches (25 centimeters) of rain was expected in some areas along the Texas coast, with even higher isolated totals possible, Brennan said. He said some higher locations in Mexico could see as much as 20 inches (50 centimeters) of rain, which could result in mudslides and flash flooding, especially in the states of Tamaulipas, Coahuila and Nuevo Leon.

At the Hotel Miramar Inn in Tampico, Mexico, near where Alberto was expected to come ashore, front desk attendant Diana Flores said the wind was gusty, but still not strong, and the rain hadn’t started yet. “There are people in the restaurant and on the beach,” Flores said early Wednesday.

Outer bands of rain lashed parts of Tamaulipas state in the northeast corner of Mexico overnight.

The storm was moving west at 9 mph (15 kph). Tropical storm warnings were in effect from the Texas coast at San Luis Pass southward to the mouth of the Rio Grande and from the northeastern coast of Mexico south of the mouth of the Rio Grande to Tecolutla.

“Rapid weakening is expected once the center moves inland, and Alberto is likely to dissipate over Mexico” on Thursday, the center said.

The U.S. National Weather Service said the main hazard for southern coastal Texas is flooding from excess rain. On Wednesday, the NWS said, there is “a high probability” of flash flooding in southern coastal Texas. Tornadoes or waterspouts are possible.

NOAA predicts the hurricane season that began June 1 and runs through Nov. 30 is likely to be well above average, with between 17 and 25 named storms. The forecast calls for as many as 13 hurricanes and four major hurricanes.

An average Atlantic hurricane season produces 14 named storms, seven of them hurricanes and three major hurricanes.

Brennan said that the first named system in the Atlantic on average comes on June 20, so Alberto is “about right on schedule.”

A no-name storm earlier in June dumped more than 20 inches (50 centimeters) of rain on parts of South Florida, stranding numerous motorists on flooded streets and pushing water into some homes in low-lying areas.

Brennan said there will be dangerous rip currents from the storm and drivers should watch out for road closures and turn around if they see water covering roadways.

“People underestimate the power of water and they sometimes don’t always take rainfall and the threats that come with it seriously, especially if you are driving in an area and you see water covering the road, you don’t want to drive into it,” Brennan said. “You don’t know how deep the water is. The road may be washed out. it doesn’t take but just a few inches of water that are moving to move your car.”