Alex "So Darn Large," But Oil-Storm Fears Unfounded?

Hurricane to devastate Gulf oil-spill effort? Probably not, experts say.
Egrets stained by the Gulf oil spill stand on an island near Grand Isle, Louisiana, Monday.

Tropical storm Alex is forecast to grow into Hurricane Alex on Tuesday, whipping up worries for communities near the Gulf of Mexico oil spill, as well as concerns that oil cleanup and containment operations could be shut down.

Despite some news reports, experts don't expect the predicted Hurricane Alex to have much effect on the Gulf oil spill situation. But, oil or no oil, some Texas and Mexico residents are bracing for what could be a bruising storm.

Since April thousands of barrels of oil have been gushing daily from the seafloor site of the BP-leased Deepwater Horizon oil rig, which blew up and sank about 130 miles (210 kilometers) southeast of New Orleans. (See "Hurricane Could Push Spilled Gulf Oil Into New Orleans.")

But tropical storm Alex will be too weak and too far away from the spill to drive oil far inland, said Stephen Pennings, a professor of biology and biochemistry at the University of Houston in Texas.

Alex is expected to make landfall as a hurricane late Wednesday or early Thursday near the Texas-Mexico border, about 600 miles (1,000 kilometers) from the Gulf oil spill. (See Gulf of Mexico map.)

"Something like the current storm will have a small effect on where the oil goes. It's not a thing to be worried about," said Pennings, a past grantee of the National Geographic Society's Committee for Research and Exploration. (The Society owns National Geographic News.)

Still, if Alex's storm surge moves the oil even a few feet farther inland, crude could enter wetlands that haven't yet been affected by the spill, Pennings said.

Spill-Response Team Girds for Hurricane Alex

The Deepwater Horizon spill-response team is taking precautions, Chris Coulon, a spokesperson for the joint federal-industry effort, told National Geographic News.

BP has suspended some spill-control operations because of tropical storm Alex, Coulon said.

But the drilling of an additional well to stop the gushing of the initial well—perhaps the effort's most important endeavor—is continuing, she said. The relief well is scheduled to be completed in August.

Worst Case: Hurricane Blasts Oil Spill

Even if it stays clear of the Gulf oil spill, tropical storm Alex is "a wake-up call, in the sense that it reminds us that the spill is in an area that gets a lot of storms," Pennings said. "And there will be a lot of oil out there for quite a while."

It would be a different story if Alex were forecast to be as powerful as 2005's Hurricane Katrina and if the hurricane's path were to take it over the site of the spill, he said.

"If a hurricane made a direct hit [on the oil spill], that could be a big driver and could really push oil miles inland," Pennings said.

Major hurricanes such as Katrina have pushed salt water far inland before and likely would do the same to spilled oil.

"That would be a huge game-changer as far as the impact of the oil," Pennings said.

Brian LaMarre, a meteorologist at the U.S. National Weather Service station in Slidell, Louisiana, said the "worst case scenario" for the Deepwater Horizon spill would be caused by a hurricane making landfall near the Texas-Louisiana border, where Hurricane Rita came ashore in 2005.

Tropical Storm Alex "So Darn Large"

Two weather fronts will determine exactly where the expected Hurricane Alex makes landfall, according to Jeff Masters, director of meteorology for Weather Underground, a private forecasting service in Ann Arbor, Michigan.

A trough of low pressure over the U.S. East Coast is pulling tropical storm Alex to the north, but a ridge of high pressure building over the storm is forcing it to the west, Masters said.

Whatever direction Alex takes, its power levels appear to be going only one way—up.

Warm seas are fuel for hurricanes, and Gulf water temperatures are currently very high. At the same time, wind shear—upper-level winds that can disrupt hurricane formation—remains low.

Even so, there's only about a 20 percent chance that Alex will become a major hurricane—a storm with winds exceeding 110 miles (177 kilometers) an hour—before it comes ashore and inevitably begins to weaken, Masters said.

As of Tuesday, Alex's tropical storm-force winds, of 35 miles (56 kilometers) an hour or greater, extend 280 miles (450 kilometers) from the storm's center, he added.

"The main thing holding it back is that it's so darn large," Masters said. "It takes time for the system to consolidate and organize and intensify."