Tropical Depression Eight Hits Tampico, Mexico

Blink, and you missed it: the latest minor blip on the almost inconsequential Atlantic hurricane season of 2013 was Tropical Depression Eight, which formed at 2 pm EDT Friday just offshore of Tampico, Mexico. The depression made landfall less than three hours later, and had top winds estimated at 35 mph. The depression has already dissipated, but brought heavy rains that were expected to accumulate to 3 - 5" along its path. Tampico, Mexico recorded 2.60" of rain from the storm.


Figure 1. MODIS satellite image of the Tropical Depression Eight, taken at 1:30 pm EDT on September 6, 2013. TD 8 was making landfall near Tampico, Mexico, with top winds of 35 mph. Image credit: NASA.

Ex-Gabrielle
The remnants of Gabrielle are generating heavy thunderstorms a few hundred miles north of Puerto Rico and the Eastern Dominican Republic, as seen on satellite loops. High wind shear of 20 - 25 knots is inhibiting development, and wind shear is expected to stay high for the next five days. NHC put ex-Gabrielle's 2-day odds of development at 20% and 5-day odds at 40% in their 8 am EDT Saturday Tropical Weather Outlook. The disturbance is headed to the north at 10 - 15 mph, and is expected to turn to the northeast and pass several hundred miles east of Bermuda on Tuesday. For such a meager storm, ex-Gabrielle will be getting a lot of attention today. NOAA is planning on flying all three of their hurricane research aircraft into the storm, and NASA will be sending up one of their two remotely piloted Global Hawks. An Air Force hurricane hunter flight is also scheduled for Saturday afternoon. With the tropical Atlantic not looking like it will generate anything more interesting to study for at least the next week, the hurricane researchers have to make do with what little they have.


Figure 2. Could this be the beginnings of the Atlantic's first hurricane of 2013? MODIS satellite image of a tropical wave emerging from the coast of Africa, taken at approximately 8 am EDT September 7, 2013. All of the models develop this wave into a tropical depression by Tuesday, and some of the models show it growing to hurricane strength by mid-week. Image credit: NASA.

New African tropical wave: is it destined to be the Atlantic's first hurricane of 2013?
A strong tropical wave is emerging from the coast of Africa this weekend, and all of the models develop this wave into a tropical depression just west of the Cape Verde Islands by Tuesday. Some of the models have been eager to intensify the storm into a hurricane by mid-week. The storm is expected to track to the northwest into a region of ocean where the Azores Islands would likely be the only land area at risk from a strike. In their 8 am EDT Saturday Tropical Weather Outlook, NHC put the 5-day odds of development at 80%.

Why such a quiet Atlantic hurricane season?
Unusual dryness over the Atlantic has been the main reason for this year's lack of hurricanes, it appears. Wunderblogger Lee Grenci's latest post, "The Lack of Atlantic Hurricanes: The Saga of Low Relative Humidity Continues", looks at how dry the Tropical Atlantic has been this hurricane season. Part of the unusual dryness, he maintains, is due to dry air coming off the coast of Brazil, which is in severe to extreme drought, according to the global drought monitor. Aon Benfield puts the cost of the Brazilian drought at $8.3 billion so far this year, making it Brazil's most expensive natural disaster in its history.

Have a great weekend, everyone!

Jeff Masters