| Category 1 hurricane (SSHS) | |
|---|---|
| Hurricane Martha on November 21, 1969 | |
| Formed | November 21, 1969 |
| Dissipated | November 25, 1969 |
| Highest winds | 1-minute sustained: 90 mph (150 km/h) |
| Lowest pressure | 979 mbar (hPa; 28.91 inHg) |
| Fatalities | 5 direct |
| Damage | $30 million (1969 USD) |
| Areas affected | Southern Caribbean basin, Panama, Costa Rica |
| Part of the 1969 Atlantic hurricane season | |
Hurricane Martha, one of the most southerly tropical storms recorded in the Caribbean, made landfall farther south than any tropical cyclone recorded in the Atlantic basin.[1] The hurricane was the eighteenth tropical storm and eleventh hurricane of the 1969 Atlantic hurricane season. Martha, the last tropical cyclone of the season, developed 99 miles (159 km) northwest of Colón, Panama, during the morning of November 21. It remained stationary and deepened to a hurricane. Martha attained maximum sustained winds of 90 mph (150 km/h) on the morning of November 22. Subsequently, Martha weakened and drifted southward. On November 24, the tropical cyclone made landfall in Veraguas Province, Panama, as a strong tropical storm. The system weakened to a tropical depression and dissipated over land on November 25.
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On November 20, the presence of an atmospheric circulation above the surface was detected in the vicinity of San Andrés, Colombia, and the Panama Canal.[2] It is estimated that Tropical Storm Martha, with winds of 50 mph (85 km/h), formed on November 21.[1] The tropical storm remained stationary and rapidly deepened. Martha strengthened at an average rate of 10 mph (15 km/h) every six hours. Martha rapidly intensified to a hurricane on the date of formation.[1] Operationally, Martha was not upgraded to a hurricane until the arrival of a reconnaissance flight, which offered confirmation that the system was a hurricane.[2] On November 22, a reconnaissance flight indicated Martha deepened to a compact hurricane,[2] and the tropical cyclone attained a maximum intensity of 90 mph (150 km/h).[1] Operationally, reconnaissance aircraft measured a minimum central pressure of 980 mbar (28.95 inHg),[3] but this value was corrected to 979 mbar (28.92 inHg) in the post-season analysis.[1][4]
Subsequently, Martha slowly moved southward, and the hurricane steadily weakened. The minimum central pressure rose to 986 mbar (29.13 inHg).[1][5] On November 23, the tropical cyclone diminished to a tropical storm,[1] and a reconnaissance flight recorded a central pressure of 999 mbar (29.51 inHg).[6] On November 24, Martha struck Panama with winds of 70 mph (110 km/h), and the last reconnaissance mission documented a pressure of 1000 mbar (29.54 inHg) before landfall.[1][7] The eye feature was 40 n mi (46 mi) wide, and it was described as poorly organized, although convection was increasing. The center rapidly dissipated as it moved ashore over Panama.[8] On November 25, the system dissipated over Panama.[1]
Residents were warned to expect tides five feet (60 in) above normal near the point of landfall.[9] Later, this prediction was lowered to three feet (36 in) above normal and pertained to tides in the Gulf of Mosquitoes and Chiriqui Lagoon. Since Martha was a relatively weak tropical cyclone, flash floods were emphasized as the greatest threat. The National Hurricane Center stated that rainfall could exceed 10 inches (254 mm).[10]
The effects of Martha resulted in five deaths, all of which occurred in Costa Rica. The nation incurred flooding from heavy rainfall, which caused significant destruction. The capital city of San Jose received flooding. In all, damages were estimated near $30,000,000 (1969 USD).[4]
Martha produced several records. It is the only Caribbean tropical cyclone of record to make landfall in Panama, [11] although it is possible that other Panama tropical cyclones were not detected.[4] The landfall in Panama represents the southernmost tropical cyclone landfall in the Atlantic basin. Few Atlantic tropical cyclones have developed farther south (9.5°N) than Martha, in 1965, 1926, 1990 and again in 2004; Martha formed near 10.3°N.[1] Hurricane Ivan also formed south of 10°N.[12]
