On September 27, a tropical wave moved off of Africa into the eastern Atlantic. It was located on the eastern edge of a monsoonal trough of low pressure, while another tropical wave was situated on the western end. For a few days, these disturbances battled it out, but the eastern one ultimately became dominant and organized into Tropical Depression Twenty on September 29. It was located in quite favorable conditions, but its large size kept strengthening gradual. The depression became Tropical Storm Victor later that day. It was the second earliest formation of a twentieth named storm on record, behind only Vicky of the previous year, which formed on September 14. Victor was named at an unusually low latitude for the Atlantic at 8.3° N.
Despite forming close to the equator, the storm gained latitude steadily as its trajectory bent from west-northwest to northwest due to the influence of an upper-level low in the subtropics eating away at the ridge that usually steers such storms west. Meanwhile, Victor managed to consolidate a little and strengthen into a high-end tropical storm with maximum winds of 65 mph and a central pressure of 997 mb. However, on October 1 it moved into the sphere of influence of the aforementioned upper-level low, which began to impart strong wind shear. At the same time, Victor reached a drier airmass. The storm steadily weakened from there on out.
The storm became a tropical depression on October 2, but intermittent convective bursts allowed it to remain a tropical cyclone for a while after that. Wind shear degraded the circulation gradually and Victor at last degenerated into a trough of low pressure on October 4.
The above image shows Victor at peak intensity, when it was already dealing with increasing shear and dry air intrusion.
During most of September, the steering pattern over the tropical Atlantic allowed tropical cyclones to escape northward, out to sea. Victor followed this pattern, avoiding land areas.
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