UNITED NATIONS (Reuters) - The world's top leaders should meet every three months, starting next year, until a plan is drawn up to reduce emissions blamed for global warming, former U.S. Vice President Al Gore said on Monday.

Gore, who has made climate change his signature issue since leaving the White House, told a U.N. meeting that presidents and prime ministers should go to Bali this year for talks on a follow-up pact to the Kyoto Protocol, which runs out in 2012.

Traditionally, environment ministers or lower-level negotiators attend the annual UN climate change talks, but Gore said leaders should go from now on and then have follow-up meetings.

NEW YORK (Reuters) - A tropical cyclone could form in the southwestern Gulf of Mexico, while a couple of tropical depressions could form in the Atlantic over the next day or two, the U.S. National Hurricane Center said Monday.

The NHC will name the next three tropical storms Karen, Lorenzo and Melissa. A tropical storm has winds of 39 to 73 mph.

In the Gulf of Mexico, three out of four weather models predict the system will steer clear of the U.S. oil and gas producing and refining facilities in the northern Gulf and make landfall in central Mexico in a few days.

DHAKA (Reuters) - More than 100 Bangladeshi fishermen were missing after at least 15 fishing boats sank in a storm in the Bay of Bengal, witnesses and officials said on Sunday.

The Chittagong port authority issued an international maritime alert advising all ships and fishing boats to remain in shelters until further notice, said Syed Farhad Uddin, the secretary of Chittagong port.

Bangladesh's meteorological department said in a special weather bulletin that the monsoonal deep depression, which hit the Bay of Bengal on Thursday night, was moving north-north-west and had reached India's eastern coastal state of Orissa.