Thursday, December 10, 2009

William Gray predicts 'above average' 2010 hurricane season

Brace yourselves: Here comes another hurricane prediction.

An early forecast for 2010 calls for an “above-average” hurricane season, according to the Tropical Meteorology Project at Colorado State University.

The team expects 11 to 16 named storms, 6 to 8 hurricanes and 3 to 5 major hurricanes — ones with sustained winds of 111 mph or greater.

Today’s prediction marks the first time William Gray’s team at CSU has provided a range of storms in its December early season forecast. The report is the team’s 27th year of hurricane seasonal predictions.

Because the report is based on Atlantic basin conditions, the team says its forecast could change substantially by the start of the hurricane season, which runs on June 1 to Nov. 30.

Gray’s team plans to list specific numerical forecasts in its next forecast on April 7.

“The Atlantic basin has the largest year-to-year variability of any of the global tropical cyclone basins,” Phil Klotzbach, the team’s leader, said in a release.

A weakening El Nino will allow more hurricanes to form, the team predicts. El Nino is a pattern of warmer-than-usual water in the Pacific Ocean, near the equator. The pattern creates more wind shear over the Atlantic, which breaks up tropical storms as they form.
“We anticipate the current El Nino event to dissipate by the 2010 hurricane season,” Gray said in the release, “and warm sea surface temperatures are likely to continue being present in the tropical and North Atlantic during 2010 — conditions that contribute to an above-average season.”

Their forecast is based on a statistical prediction scheme that uses 58 years of “hindcast” data. Over that time period, the scheme correctly forecasted above- or below-average seasons in 44 out of 58 years, the team said.

For the 2010 Atlantic basin hurricane season, the CSU hurricane forecast team expects:

# A 64 percent chance that at least one major hurricane will make landfall on the U.S. coastline in 2010. The long-term average probability is 52 percent.

# 40 percent chance (the long-term average is 31 percent) of a major hurricane making landfall along the U.S. East Coast, including the Florida Peninsula.

# A 40 percent chance (the long-term average is 30 percent) of a major hurricane making landfall along the Gulf Coast, from the Florida Panhandle west to Brownsville.

The full report.

No comments: