Tropical Storm Gordon forms; 5th earliest appearance a season's 7th storm

Tropical Storm Gordon is here, born out of a tropical wave that emerged from the coast of Africa last week. Gordon's formation puts the hurricane season of 2012 in fifth place for the earliest date of formation of the season's seventh storm, going back to 1851. Only 2005, 1936, 2011, and 1995 had earlier formation dates of the season's seventh storm. Satellite loops show Gordon has developed a Central Dense Overcast (CDO)--a large and expanding area of high cirrus clouds over the center, due to a build-up of heavy thunderstorms. This is characteristic of intensifying tropical storms. Wind shear is light, but ocean temperatures are on the cool side, near 27°C. Water vapor satellite loops show that Gordon has moistened its environment considerably, but a large region of dry air lurks on three sides of the storm, ready to barge in and disrupt Gordon when wind shear rises on Saturday. The 8 am EDT run of the SHIPS model predicts that wind shear will remain light to moderate through Friday, then rise steeply to 25 - 40 knots over the weekend. At the same time, ocean temperatures will drop to 26°C. By Sunday, the combined effects of high wind shear, dry air, and cooler waters will likely act to weaken Gordon and make it no longer tropical, but Gordon will probably still be strong enough Sunday night to potentially bring damaging winds and heavy rain to the Azores Islands.


Figure 1. Morning satellite image of Tropical Storm Gordon.

Gordon's place in history
The 2012 version of Gordon is the fourth storm that has been given that name. Previous incarnations of Gordon appeared in 1994, 2000, and 2006. It's pretty unlikely that the 2012 version of Gordon will get its name retired, but the name Gordon should have been retired long ago. During the first appearance of Gordon in November 1994, the storm moved very slowly over Eastern Cuba, and dropped prodigious rains over Haiti. The resulting flash flooding killed over 1,100 people. Unquestionably, the 1994 version of Gordon should have had its name retired, due to the devastating impact it had on Haiti. However, after the 1994 hurricane season, Haiti did not send a representative to the annual World Meteorological Organization meeting that decides retirement of hurricane names, and no other country affected by Gordon requested that the name be retired.


Figure 2. Track of the 1994 version of Hurricane Gordon. The storm killed over 1100 people in Haiti.

Elsewhere in the tropics
In the Gulf of Mexico, a fall-like cold front is expected to stall out early next week. Wind shear is predicted to be low to moderate, and cold fronts stalled out over the Gulf of Mexico often serve as the seed for tropical storms. The most likely formation location of such a storm would be off the Texas coast, or off the Mexican coast south of Texas.

A large tropical wave is emerging from the coast of Africa today, and the GFS and ECMWF models predict this wave will develop into a tropical depression 4 - 5 days from now. Preliminary indications are that this new storm will follow a path similar to Gordon's, recurving to the east of Bermuda, but it is too early to be confident of this.

Jeff Masters