Corps meteorologist: Don’t expect ‘black rain’ from Gulf Coast
Published 12:00 pm Wednesday, June 16, 2010
The threat of an active hurricane season coinciding with the nation’s worst oil spill on record won’t bring any “black rain,” but could become a problem where storm surge is concerned, the National Weather Service’s chief local meteorologist said Tuesday.
In May, the weather service predicted 14 to 23 named storms for 2010, with three to seven major hurricanes — all based on warmer sea surface temperatures in the Caribbean Sea and the Atlantic Ocean and a generally neutral pattern between El Nino and La Nina climate patterns.
Bill Frederick, head meteorologist for the NWS office in Vicksburg and liaison between the weather service and the Corps of Engineers’ Mississippi Valley Division, told the Vicksburg Kiwanis Club a hurricane in the Gulf of Mexico would churn and probably dilute the millions of gallons of crude left from remnants of the Deepwater Horizon oil rig, then deliver it to shore with the surge.
“The only problem is if it brings contaminated oil in shore,” Frederick said. “It should be mixed up by the hurricane itself. There will be no ‘black rain’ as people are talking about because a hurricane is massive. An oil spill is small in comparison.”
Hurricane Ida was the strongest storm to strike the U.S. during the 2009 Atlantic hurricane season, but reached just Category 2 wind speeds at its peak.
This season, less wind shear from westerly steering currents from last year’s El Nino is primed to create “generally ideal conditions” for tropical storm and hurricane development, Frederick said.
“We’re in neutral right now, but expect it to shift to La Nina here by August. We’ll see,” Frederick said. “Last year, we didn’t have a lot of activity — we were in El Nino. Everything was out in the Atlantic. This year, we’re probably going to get Caribbean and Gulf of Mexico storms.”
In general, storms that form during periods of neutrality between the two patterns have made landfall along the U.S. Gulf Coast — the most powerful examples being Hurricanes Katrina and Rita in 2005 and Andrew in 1992. El Nino, present for much of 2009, creates wetter but cooler winters in the South and into Mexico but has pushed storms east of Mississippi and Louisiana. La Nina patterns cause more activity in the Atlantic basin, of which the Gulf States are a part, but trends show southerly tracks into Mexico and Central America during those years, notably Hurricane Gilbert in 1988 and Hurricane Mitch in 1998. Both rank in the top 10 for the lowest atmospheric pressure ever recorded.