Forecasters are not only calling for an above-average hurricane season — they're also saying there is a greater chance that a storm will strike the Gulf Coast. Barry Keim, Louisiana state climatologist, told the Baton Rouge Press Club on Monday that a new publication from Colorado State University's Philip Klotzbach and William Gray says there is a 47 percent chance a hurricane will hit the Gulf Coast this year.

There is also a 47 percent chance a hurricane will make landfall in Louisiana, and a 20 percent chance for a major hurricane to make landfall in the state, according to the report.

"It doesn't bode well," Keim said.

The only state with a higher chance that a hurricane will make landfall is Texas, which has a 50 percent chance, according to the report.

Last year, Klotzbach and Gray predicted 18 named storms, Keim said. The season ended with 19 named storms, which tied for third as the most active season on record. In addition, the National Oceanic and Atmospheric Administration's forecast released May 19 also predicted an above-average hurricane season.

NOAA's forecast calls for 12 to 18 named storms, with six to 10 of them becoming hurricanes, and three to six of them becoming major hurricanes, Keim said.

"All indicators suggest it's going to be busy (this year)," Keim said.

Part of the reason is the Atlantic Ocean is in a period of warmer than normal sea surface temperatures, which began in 1995.

In Klotzbach and Gray's updated forecast released June 1, the duo says that there were 25 major hurricanes in the Atlantic Ocean from 1979 to 1994.

A major hurricane is one that becomes a category three hurricane or stronger.

The new, more active period started in 1995, and there have been 61 major hurricanes in the Atlantic Ocean from 1995 to 2010.

The warmer waters help provide the energy thunderstorms need to become tropical storms and hurricanes.

In addition, although the La Niņa weather pattern is disappearing, the effects of low wind shear are expected to continue into the hurricane season, Keim said.

Although hurricane season officially started June 1, historically there haven't been many storms that form before August, he said.

The peak time for tropical storm development runs three to four weeks on either side of Sept. 10 — a date where sea surface temperatures historically have reached their warmest point, he said.

Between 1886 and 2006, there have been 15 named storms in May, 67 in June and 89 in July, Keim said.

Those numbers jump to 270 named storms in August, 365 storms in September and 223 storms in October, he said.

Although there have been 53 storms that have formed in November, so far, a storm has not made landfall in Louisiana in November, Keim said.

By AMY WOLD
Advocate staff writer
June 7, 2011