Around October 10, yet another late season tropical wave entered the eastern tropical Atlantic. The system gained organization as it moved westward and appeared to be close to tropical depression status on October 14. However, no well-defined center formed, and conditions became a little less favorable over the next few days. Thunderstorm activity in association with the broad low became more diffuse, and it took even more time for it to regroup. It wasn't until October 18 that the system finally was upgraded to Tropical Storm Tammy. At that time, it was 1000 kilometers east of the Windward Islands.
Tammy developed a fairly impressive central dense overcast and had good inflow on satellite imagery, but the vortex also showed clear tilt and was elongated northwest to southeast. This limited significant strengthening in the short term, but aircraft reconnaissace did find that Tammy was producing sustained winds of around 60 mph on October 19, making it a fairly strong tropical storm. The next day, the cyclone reorganized somewhat and developed a very small core. This led to a short burst of intensification and Tammy was a category 1 hurricane late that morning. The storm gradually turned toward the northwest as it approached the Lesser Antilles. Its center passed just to the east of Martinique and Dominica on the morning of October 21. Though scattered heavy rainfall was widespread across the nearby islands, the small windfield of Tammy kept hurricane-force winds off of land for the most part.
After a bit more strengthening, Tammy reached its first peak intensity of 85 mph winds and a pressure of 988 mb later on the 21st. The center made a direct landfall in Barbuda that evening, bringing severe impacts to the small island. After that, the storm moved gradually away from the Caribbean islands, though rainfall lingered from the outer bands through October 22. The storm continued to round the periphery of the subtropical ridge and turned north. It maintained category 1 strength and continued to exhibit a small but powerful area of central convection.
In the subtropics, Tammy turned northeast and encountered a more diffluent upper-level environment. This began another period of strengthening late on October 24 and an eye appeared on satellite imagery the next morning. Tammy soon reached its peak intensity as a category 2 hurricane with 105 mph winds and a minimum pressure of 965 mb. Later in the day, stronger shear set in as the storm began to interact with a nearby front and weakening began. The storm underwent a rather quick extratropical transition early on October 26. Little more than a day later, though, ex-Tammy separated from the front and became a tropical cyclone again. At that point, it was estimated to be a strong tropical storm in intensity.
The storm remained very compact, with deep convection occurring only very close to the center. Therefore, even though it was rather close to Bermuda, the island did not receive any severe impacts. It moved south of east away from Bermuda after that and gradually weakened due to dry air around it. Warm ocean waters could not counteract the unfavorable atmospheric environment and Tammy lost deep convection by late on October 28. It became post-tropical for the final time early on the 29th.
The image above shows Hurricane Tammy at peak intensity as a category 2 on October 25.
Tammy's primary impacts were to the Leeward Islands.
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