Those of us on the Texas and Louisiana Gulf Coasts are breathing huge sighs of relief today!

The 2009 hurricane season officially ends today with just nine named storms having developed in the Atlantic basin, a nice break after the disastrous 2008 season that sent Hurricane Ike barreling into Galveston Island. Here are four things we know after six months of tracking the tropics, and one thing we don’t.

What we know

El Nino matters: Although an El Nino occurs in the Pacific Ocean, where tropical sea temperatures are abnormally high, the climate pattern tends to increase wind shear over the Atlantic basin. That’s exactly what happened this season, and it’s no coincidence that two of the quietest seasons in recent history (2006, with 10 named storms, and 2009) developed under the influence of El Nino.

Late starts are rare in satellite era
This season was notable for its late start, with the first named system, Tropical Storm Ana, not developing until Aug. 12. It was the latest start since 1992, when Hurricane Andrew formed on Aug. 16 before spinning into a Category 5 storm. With satellites now monitoring the tropics 24 hours a day, hurricane scientists no longer miss early season systems that spin up briefly into tropical storms before dissipating.

Modern government moves slowly
A year after Galveston’s Great Storm in 1900, the city had hired engineers to design a seawall, and construction began in 1902. Two years later, the city began bringing in 16 million cubic yards of sand to raise the island. Today, more than a year after Hurricane Ike, local governments are just getting around to forming a six-county “surge-suppression zone” to study whether to do something about catastrophic storm surges like the one generated by Ike.

2005 was an anomaly
Four years ago, some hurricane scientists wondered whether the 2005 Atlantic season, with its 28 named storms, including famously intense Katrina, Rita and Wilma, was the new normal for the Atlantic basin in a warming world. But since then, the Atlantic basin has averaged 13 named storms a year, and global activity has been at its lowest level since the satellite era began 30 years ago.

What we don't know

Will Texas quiet back down?:
From 1989 through 2006, Texas only experienced three hurricanes — Jerry in 1989, Bret in 1999 and Claudette in 2003. That’s a 17-year stretch. Then, in less than 17 months during 2007 and 2008, three hurricanes — Humberto, Dolly and Ike — struck the state. And that doesn’t even count Hurricane Rita in 2005, which devastated East Texas but technically made landfall just inside the Louisiana border. Historically, Texas averages four hurricane strikes a decade, and got the most in the 1950s with 10 strikes. Are we returning to that era after an extended period of calm?

http://www.chron.com/disp/story.mpl/news/specials/hurricane/6744673.html