La Nina easing, may reduce risk of hurricanes through Autumn

11.07.08 13:17

The climate phenomena known as La Nina is ending and neutral conditions are expected into the the last three months of the year, U.S. government forecasters said Thursday. The change can affect weather worldwide.

La Nina is a cooling of water in the tropical Pacific Ocean, the opposite of the warm-water condition known as El Nino.

The federal Climate Prediction Center said a transition from La Nina to neutral conditions occurred during June as sea surface temperatures returned to near average conditions.

The transition to a neutral condition could be beneficial along the East and Gulf coasts of the U.S. with hurricane season under way, as the chances for the continental U.S. and the Caribbean Islands to experience a hurricane are higher during La Nina.

However, the forecast also noted that, as in past transitions first reported from changes in sea surface temperatures, La Nina's effects can linger in the atmospheric circulation, but with diminishing strength.

The National Oceanic and Atmospheric Administration's Atlantic hurricane outlook issued in May calls for 12 to 16 named storms including 6 to 9 hurricanes. Currently the second named storm of the season, Bertha, is churning in the mid-Atlantic.

While the forecast calls for neutral conditions to continue into the the last months of the year, the Climate Prediction Center said it could not rule out a change at that time, as El Nino-La Nina switches often occur in the second half of a year.

By: Randolph E. Schmid