Tropical Storm Hermine, now in the Gulf of Mexico, might make landfall on northeast Mexico state Tamaulipas, and cause heavy rains and a surge of water in major rivers there, the National Meteorology Service (SMN) said Monday.

"We forecast Hermine will turn northeast and increase speed so that it will affect northeastern Mexico and southern Texas in the early hours of Tuesday," the SMN said.

Hermine, the eighth named storm of the Atlantic hurricane season, has sustained winds of 75 kilometers an hour (kph), with gusts reaching 90 kph. The tropical storm force winds extended out up to 165 kilometers from the storm's center.

The SMN forecasts heavy rains in the center, east, north and northeast of the nation, and moderate rains in Caribbean coast states. East coast state such as Tabasco, Tamaulipas, Veracruz and Yucatan will also experience strong winds.

More than 250,000 people have suffered heavy rain and floods in Mexican states Oaxaca, Veracruz and Tabasco, the Interior Ministry's civil protection coordinator Laura Gurza said, adding that the Mexico-U.S. border areas are now at risk of a third round of heavy rains caused by Hermine.

Tlacotalpan, a port town in Veracruz, is completely underwater and 65 percent of the population has been evacuated. The rain is Veracruz's worst in 40 years, the state's civil protection director Silvia Dominguez said.

The government has already prepared food, bedclothes and tools for affected areas, but may resort to airdrops as it is hard to reach the flooded areas of Oaxaca.