Tropical Storm Becky (1970) - Meteorological History

Meteorological History

On July 16, 1970, a large disturbance separated from the Intertropical Convergence Zone near Panama. The broad area of convection dominated the region between Swan Island and western Cuba by July 18. Some sources state that the area of convection was joined by a low-level vortex that entered the area, eventually forming a depression. Others believe that the origins of Becky can be tracked back to a tropical wave that moved off the coast of Africa on July 9. A tropical depression formed on July 19, 1970. As the depression moved through the Yucatan Channel, the convective cloud system became better organized. On July 20, in light of data from a Reconnaissance Aircraft flight, the depression was upgraded to Tropical Storm Becky.

The storm moved roughly northward under the influence of the Bermuda High to the east and a low pressure area over Mexico. Reports from a Reconnaissance flight indicated that Becky was disorganized, with a minimum barometric pressure of 1,008 mbar (29.8 inHg). Although a fairly strong low-level circulation developed, there was insufficient warming of the center to produce a significant drop in barometric pressure at the surface. Late on July 20, a ship reported a minimum pressure of about 1,003 mbar (29.6 inHg), and another ship reported sustained winds of 65 mph (100 km/h), which would be Becky's peak intensity. A Reconnaissance flight and weather radars suggested the development of an eye feature, and initially it was believed that the storm attained minimal hurricane status. Later it was later confirmed that Becky remained a tropical storm, and the previously forming eye failed to persist.

On July 21, the storm deteriorated in organization as it continued northward. The lack of banding features indicated that by early on July 22, Becky was barely a tropical storm. The storm made landfall near Port St. Joe, Florida shortly thereafter, and weakened rapidly as it moved inland; as a rainstorm, it progressed northward into the Midwestern United States and completely dissipated over Michigan.