MIAMI (Reuters) - Tropical Storm Maria formed in the Atlantic today while Hurricane Katia churned up the surf along the beaches of Bermuda and the eastern United States, the U.S. National Hurricane Center said.Maria could threaten Puerto Rico and the Leeward Islands of the northeast Caribbean during the weekend, but posed no immediate danger to land.It was about 1,305 miles (2,095 km) east of the Lesser Antilles and racing rapidly westward. Maria had top winds of 50 miles per hour (85 km per hour) and could strengthen slightly in the next two days, forecasters at the hurricane center in Miami said.Computer models showed it turning northwest early next week but it was too early to know whether Maria would then curve away from the United States, like Katia is forecast to do. Some forecasts have it turning towards Bermuda.Katia has weakened significantly in the last two days but is still a hurricane with 85 mph (140 kph) winds, making it a Category 1 storm on the five-step Saffir-Simpson intensity scale. It was a Category 4 at its peak.Katia was centred about 320 miles (515 km) southwest of the mid-Atlantic island of Bermuda and was expected to pass between the eastern U.S. coast and Bermuda by Thursday.Forecasters said the core of the storm would stay out to sea, but Katia was so wide that its outer squalls could reach the shores of Bermuda.Katia generated large swells that kicked up the surf and caused dangerous rip currents along the beaches of the Eastern United States, Bermuda, the Greater Antilles and parts of the Bahamas, the forecasters said.Once past Bermuda, Katia is forecast to curve eastward over open seas where it would pose no further threat to land.Neither Maria nor Katia was near the Gulf of Mexico, where U.S. oil and natural gas operations are concentrated.But forecasters were keeping watch on a disturbance in the southwest Gulf of Mexico that they gave a 60 percent chance of developing into a tropical cyclone in the next few days.Computer models varied widely as to its potential path. Some took it west over Mexico while at least one took it northeast toward the Louisiana-Mississippi coast.The flurry of tropical disturbances is not uncommon for September, the traditional peak of the June-through-November Atlantic hurricane season.