El Nino ends, La Nino begins
The winds that disrupt hurricanes headed for the United States end
NOAA's Climate Prediction Center announced that conditions are favorable for a potentially volatile storm season, causing concern, particularly on the Gulf Coast
Communities along the Gulf Coast still reeling from Hurricane Katrina and recent tornados got some more bad news recently regarding the 2007 hurricane season. La Nina appears to be on its way
National Oceanographic and Atmospheric Administration's Climate Prediction Center announced Feb. 27 that a weak El Nino has ended and conditions are favorable for a potentionally volatile La Nina.
La Nina, which typically comes about every three to five years and last anywhere from nine to 12 months, happens trade winds from the east push warm surface waters to the western Pacific. This condition tends to inhibit the formation of strong upper-level winds that can shear the tops off hurricanes developing in the Atlanta Basin and make them less threatening. During La Nina, more named storms form in the deep tropics from weather systems that move off Africa, according to Climate Prediction Center officials. The means that the systems are more likely to become major hurricanes that threaten the United States, particularly the Gulf Coast from Texas to the Florida Keys, and north through the Carolinas.
That's anything but good news for folks in Louisiana and Mississippi trying to rebuild their lives after Hurricane Katrina. The same goes for the communities in Alabama, Georgia and Florida trying to dig their ways out after devastating and deadly tornados the last month.
El Nino, which had been dominant this winter, is just the opposite of La Nina. El Nino is a warm current of water that appears every three to seven years in the eastern Pacific Ocean and influences weather configurations across the world. In El Nino, weakened trade winds allow warm surface water in the Pacific to move back to the east. This tends to cause more rain in coastal regions and generate strong upper-level winds that can shear the tops off hurricanes forming in the Atlantic Basin.
Any shear has a tendency to pull the storm apart, according to the National Weather Service in Miami. That's why NOAA's forecast could be particularly bad news for area's in Louisana, Mississippi, Alabama and Florida, area's most hit by hurricanes. La Nina inhibits the development of those storm-disrupting winds.
The 1999 hurricane season, plagued by La Nina, produced 12 named storms, including eight hurricanes and five Category 4 hurricanes, at the time a record.
