Tropical Storm Alex is bearing down on the coast of Belize as it tracks toward the Gulf of Mexico, raising concerns of its potential impact on the efforts to cleanup the massive oil spill there.

Alex, with maximum sustained winds of 100 kph, was expected to make landfall on Belize overnight Saturday, before heading overland across Mexico's Yucatan Peninsula and into the southwestern gulf.

Preparations were underway in Belize all day Saturday, as officials opened storm shelters and facilitated the evacuation of tourists and residents from low-lying islands along the coast.

Torrential downpours and heavy winds were reported on the offshore islands Saturday afternoon, as the U.S. National Hurricane Center reported the storm was centered just 25 kilometers east-southeast of Belize City.

The storm was expected to bring with it a surge of up to 1.5 metres along the country's northern coast.

The tropical storm warning extended along Mexico's entire Caribbean coastline up to Cancun. Although Quintana Roo state authorities said conditions were too dangerous to swim, there was otherwise no danger to the popular tourist areas Cozumel, Playa del Carmen and Tulum in the region.

Beside the danger to people in its path, Alex is the first storm of the season to threaten containment efforts directed at the spill that has fouled the Gulf with as many as an estimated 500 million liters of crude.

This first tropical depression of the summer season formed Friday off the coast of Honduras. It escalated to a tropical storm -- one step below a hurricane -- early Saturday.

According to the latest U.S. National Hurricane Center forecast,

Alex will likely lose strength as it passes over the Yucatan Peninsula, before picking up steam again over the Gulf of Mexico.

From there, Alex is expected to track through the southwestern Gulf and toward landfall around Veracruz or Tamaulipas state in Mexico — possibly as a hurricane.

Experts warn that prediction could quickly change.

Should the storm take an unexpected sharp shift North, there are fears it could seriously disrupt the armada of ships now working on cleanup in the Gulf.

Removing the flotilla of boats and cleanup equipment alone would take about five days, and it would be about two weeks before work could resume, said Adm. Thad Allen, the Coast Guard officer who is heading up the clean-up efforts.

It would also likely mean that a cap that has been siphoning oil from the well would have to be temporarily removed. The ships that have been processing and storing the crude as it is sucked up would also have to leave the area, meaning the well would be free to once again gush unchecked.

A tropical storm could also damage hundreds of kilometres of boom, which has been put in place to contain some of the oil.

Crews have tried a number of initiatives to halt the flow of oil from the well that exploded on April 20, from installing caps to trying to plug the well with garbage, but have so far been unable to completely halt the flow.

The best hope purportedly lies in two relief wells that BP is currently drilling in an attempt to take pressure off the leaking well.

That plan requires BP to drill through over two miles of rock from the ocean floor -- a tedious process that has been underway since early May. The wells should eventually intersect the ruptured well, at which point crews will pump heavy drilling mud into the fissure to block the flow of oil.

The oil giant said Friday that plan is on target.

The current weather situation comes after BP's top executive was publicly chastised by U.S. President Barack Obama, then demoted.

Public frustration has been mounting as numerous attempts to stop the leak have failed, with an estimated 69 to 132 million gallons of crude oil believed to have spilled into the Gulf.

On Friday, BP's stocks hit a 14-year low on the New York Stock Exchange. The company, which has lost more than US$100 million in market value, has spent $2.35 billion dealing with the disaster, with no end in sight.