The initial disturbance which led to this cyclone’s development moved off the coast of Africa on October 5th.The system moved westward without note until the 9th when the convective system began to detach from the Intertropical Convergence Zone. By the afternoon of the 10th, the system became a tropical depression, the 17th of the season. Late that night the system became a tropical storm named Joan. Moving westward, the cyclone began to weaken as it approached the Windward Islands. The cyclone moved across Grenada, and slowly developed as it grazed the coast of South America, the first to track so far south since 1971. The cyclone moved across Curacao, the Paraguana peninsula of Venezuela, and the Guajira peninsula of Columbia. After
clearing the Columbian peninsula, Joan strengthened into a hurricane. The cyclone transcribed a loop about 130 miles north of Panama City, Panama on the 20th. Tropical Depression #18 may have helped contribute to this motion.

Strengthening resumed after the loop, and Joan became a category 4 hurricane to the east of Bluefields,Nicaragua. Moving acorss Nicaragua on the 22nd and early on the 23rd, the cyclone remained well-organized and at tropical storm strength as it emerged into the eastern Pacific ocean. The system was named Miriam upon entering the Pacific, and moved just offshore El Salvador and southern Guatemala before upper level shear weakened the tropical storm with the system dissipating as a tropical cyclone about 300 miles south of Acapulco on the 28th. Below is the track of this cyclone, provided by the National Hurricane Center.

The graphics below show the storm total rainfall for Joan/Miriam. Note the maxima over the Yucatan Peninsula and extreme southeast Mexico, which occurred under inflow bands to the northeast of the cyclone. Rainfall data was provided by the Comision Nacional del Agua, the parent agency of Mexico’s National Weather Service.

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A tropical wave moved off the west coast of Africa on September 7th and 8th, accompanied with a large low to mid-level circulation, but little thunderstorm activity. The system progressed westward through the tropical Atlantic, and deep convection formed near the circulation on the 12th. Now a tropical depression, the cyclone moved west-northwest and strengthened quickly, becoming a tropical storm early on the 13th and a hurricane that evening. Moving towards a weakness in the west-central Atlantic, the system moved more northwestward as it moved through the northeast Caribbean. The center passed just north of Barbados and Martinique before moving over Dominica and southwest of Guadeloupe. As a strengthening category 2 hurricane, Marilyn moved through the U.S. Virgin Islands late on the 15th. Hail was noted at this time near its center, which is unusual for tropical cyclones. Its eyewall passed directly over St. Thomas and east of Puerto Rico into the southwest Atlantic.Marilyn ultimately strengthened into a category 3 hurricane as it turned northward towards Bermuda. A combination of vertical wind shear and cool waters previously upwelled by Hurricane Luis caused Marilyn to weaken late on the
17th and early on the 18th. Moving north-northeast, the hurricane passed about 150 miles west of Bermuda.Vertical wind shear increased, which partially exposed its low level center late on the 21st. Considered extratropical when convection no longer existed near the center on the 22nd, Marilyn meandered for another 10 days before becoming absorbed into an approaching frontal system on October 1st. Its track lies below,provided by the National Hurricane Center.Below are the storm total rainfall maps for Marilyn. Rainfall information was obtained from the National Climatic Data Center (for Puerto Rico and the U.S. Virgin Islands) and the National Hurricane Center Tropical Cyclone Report on this storm.

<<Retired Hurricane