Mexican authorities opened shelters and warned residents to watch for mudslides Monday as Tropical Storm Hermine approached its northeastern border with the US state of Texas, the second major storm to hit the area this season. Hermine could approach hurricane strength before hitting land early Tuesday in a sparsely populated area about 80 kilometers south of Matamoros, a Mexican city bordering Brownsville, Texas, the Miami-based National Hurricane Center (NHC) said. Mexican emergency officials urged people living in low-elevation coastal areas to move to shelters, but there were no immediate evacuation plans. "We urge the general population to be on alert for possible floods and mudslides," said Tamaulipas state civil-defense director Salvador Trevino. With maximum sustained winds of nearly 80 kilometers per hour (kph), Hermine was located about 330 kilometers southeast of Brownsville at 1500 GMT and was moving north-northwest near 21 kph. Heavy rain is forecast, with northeastern Mexico into south Texas receiving 10 to 20 centimeters, and up to 30 centimeters is possible in some places.