Around August 14, a tropical wave around halfway between west Africa and the Caribbean showed some modest signs of organization. It moved roughly west-northwestward over the next few days. By the 16th, a large area of vorticity was had developed across the eastern tropical Atlantic, with the aforementioned disturbance at its western end. Weak low pressure centers formed at both ends; the eastern one eventually became Tropical Storm Emily. Around August 17, another low actually formed even farther west of our system, still associated with the overall monsoon trough. That low moved into the Caribbean and eventually became Franklin. All of this interaction made it harder for the system to consolidate; in addition, the farther north the disturbance tracked, the closer it came to a large area of Saharan dry air. Nevertheless, the western low ultimately became better defined and deep convection persisted near the center long enough that it was classified Tropical Depression Six on August 19.
By the time it formed, Six was around 850 miles east of the northeasternmost Caribbean islands. However, there was an upper-level trough located near the greater Caribbean islands, which sheared the storm more strongly as it continued westward. It struggled to maintain thunderstorm activity over the center on August 20. Despite all of its struggles, the cyclone produced vigorous enough convection to generate gale force winds that night and was upgraded to Tropical Storm Gert early on August 21. The storm began to weaken again soon after and became a tropical depression later that day. Gert persisted longer than expected, but ultimately weakened into a remnant low on August 22, not too far from the Leeward Islands.
Gert's remnants turned north-northwest and very slowly moved toward the subtropical Atlantic. After about a week of this, a low-pressure redeveloped in association with the system, and it began to get better organized again. On September 1, a remarkable ten days after ceasing to be a tropical cyclone, the disturbance was once again Tropical Depression Gert. Nor did it stop there. That afternoon, its cloud pattern became more organized and it strengthened into Tropical Storm Gert. At first, the storm didn't move very much, but it soon felt the influence of an extratropical low to its west, which was the remnant of Hurricane Idalia. This steered Gert toward the north-northeast with increasing speed. Despite some northerly wind shear, it strengthened on September 2, reaching a peak intensity of 60 mph winds and a central pressure of 998 mb.
At last, the hostile atmospheric environment began to take a toll on Gert. It weakened a little and most thunderstorm activity was stripped away from the center on September 3. The small cyclone turned north and then west of north as it spiralled toward the powerful ex-Idalia located southeast of Atlantic Canada. It dissipated and merged with this larger storm late in the morning on September 4.
The image above shows the small but persistent Tropical Storm Gert on September 3. The edge of the cloud pattern of the extratropical low which was once Hurricane Idalia is visible at left.
Gert had an unusual history, with two periods of time as a tropical cyclone separated by 10 days as a disturbance wandering the western Atlantic.
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