Thursday, February 18, 2016

Hurricane Betsy

Bahamas–Southern United States, August 22–September 10, 1965 

One of the most powerful Category 4 hurricanes on record, Betsy blazed an unusual loop-the-loop track of death and destruction through the central Bahamas, south Florida, and the gulf coasts of both Louisiana and Mississippi between August 27 and September 9, 1965. With central barometric pressures at landfall ranging from 27.61 inches (935 mb) in the Bahamas, to 28.14 inches (953 mb) in Florida, to 27.99 inches (948 mb) in Louisiana, Betsy’s 147-MPH (237-km/h) winds, flooding rains, and 6-foot (2-m) storm surge wrought an estimated $1.4 billion in property damage, making it one of the most costly hurricanes to have affected the United States up to that time. Seventy-five people, a majority of them in Louisiana, lost their lives to the terrifying depredations of this unpredictable midseason storm.

The second tropical cyclone of the rather tame 1965 hurricane season, Betsy originated in the Windward Islands, 350 miles (563 km) eastsoutheast of Barbados, on August 27. Moving northwest at just over eight MPH (13 km/h), the embryonic hurricane slowly but inexorably gained strength from the 82 degree F (28°C) waters of the east Caribbean Sea. On August 28, Betsy’s tropical storm-force winds lashed the east coast of Guadeloupe, driving a minimal one-foot storm surge into the harbor at Pointe-à-Pitre, but claiming no lives on the picturesque French dependency. Firmly committed to its northwest course, Betsy continued to intensify during the night of August 29, with a minimum pressure of 29.73 inches (1,007 mb) being recorded by aircraft reconnaissance just before dawn on August 30. However, during the early morning hours of August 31, while Betsy’s eye was located 275 miles (443 km). northeast of Puerto Rico, the hurricane came under the steering influence of an enormous high-pressure ridge that had settled in over eastern United States. Now boasting a central pressure of 29.23 inches (990 mb) and sustained winds of 83 MPH (134 km/h), Betsy began to execute a sharp clockwise loop, first moving northeast, east, and southeast, before setting off for the southwest by midafternoon on September 1. The hurricane’s barometric pressure continued to fall during its course change, with an aerial reading of 28.93 inches (980 mb) being taken just before dusk on September 1.

Forced southeast by the encroaching high-pressure ridge, the swiftly intensifying Betsy continued to move in that direction throughout the afternoon and evening hours of September 1. With Betsy’s central pressure rapidly approaching 28.10 inches (951 mb), civil defense officials in Haiti and Jamaica prepared their respective organizations for the possibility of a destructive strike from the approaching hurricane. While there were indications that Betsy would eventually return to its initial northwest course once it had cleared the high-pressure ridge, both nations— each with its own history of deadly hurricane landfalls— stood waiting to evacuate their low-lying coastline communities, issue flash-flood warnings, and close down their airports. As it was, Betsy’s expected course change came shortly before midnight on September 1 when the hurricane began to recurve to the northwest, returning it to its original course but nearly 500 miles to the west. Still intensifying, Betsy’s central pressure dropped to 27.81 inches (942 mb) by noon on September 2, boosting its winds to a dangerous 110 MPH (177 km/h). Evacuation concerns now shifted to the Bahamas, the shallow basin of islands that lie off the east coast of Florida, where beachside resort hotels and sumptuous casinos were cleared of patrons and staff alike and then secured against Betsy’s winds and rains with storm shutters and sandbag barricades.

With its forward speed reduced to a pedestrian four MPH (6 km/h), Betsy languidly moved northwest, skirting the east coast of Turks and Caicos Islands during the early morning hours of September 2. The squat islands were rigorously assailed by 130- MPH (209-km/h) winds and five inches (127 mm) of rain, uprooting coconut palms and telephone poles but causing no fatalities. On September 3, just as Betsy’s roiling eye passed over Cat Island, the hurricane achieved its lowest recorded barometric pressure, 27.61 inches (946 mb). Cataracts of rain showered the sandy key, washing out bridges and roadways. 

Two small reef-diving boats, equipped with glass bottoms for undersea viewing, were driven ashore by the storm’s bulging surge and quickly broken up. Now located 430 miles (692 km) south of Cape Hatteras, North Carolina and bound for the Bahamian capital of Nassau, Betsy again stalled on September 4 as the western edge of the mounting high-pressure ridge continued to sag to the south. In an almost mirrorimage of its earlier maneuver, the hurricane’s eye performed another loop-the-loop course change. First swinging to the north, then to the north east, and then back toward the south again, Betsy pirouetted throughout the day of September 5, coming to rest shortly after midnight on a southwesterly tack that, if maintained, would take the hurricane’s furious eye ashore somewhere in the vicinity of Havana, Cuba, on either September 7 or 8.

Now regarded as one of the most unpredictable hurricanes to have moved through the Caribbean in several years, Betsy maintained its southwesterly progression over the central Bahamas and toward Florida’s southeast coast between September 6 and 7, 1965. During this time, the storm experienced the barometric vagaries generally associated with erratic hurricane behavior as its central pressure rose from 27.93 inches (946 mb) on September 4, to 28.11 inches (952 mb) on September 5, to 28.52 inches (966 mb) on September 6. By the morning of September 7, as the hurricane began to swing due west—in the process, threatening the southernmost tip of the Floridian peninsula—its barometric pressure again began to drop, reaching 28.26 inches (957 mb) by midafternoon. This ominous development, along with Betsy’s strident course to the west, prompted civil defense authorities in Florida to order a costly evacuation of all low-lying coastal communities from Miami to Key West. Tens of thousands of tourists, many of them in attendance for the state’s Labor Day festivities, were hurriedly cleared from palatial hotels and shorefront bungalows, while native Floridians rushed to board up their windows, stockpile food and medical supplies, and secure their boats from Betsy’s anticipated seven-foot storm surge.

With a central pressure of 28.14 inches (953 mb), Betsy blasted ashore near Biscayne Bay, just south of Miami, Florida, on the morning of September 8, 1965. Gusts of 135 MPH (217 km/h) drove before them five to nine–foot (2–3 m) storm surge, the highest seen on Florida’s southeast coast in nearly a quarter of a century. Betsy’s brutal winds and pounding rains stripped trees of their foliage and buildings of their roofs and siding, crumpled billboards, toppled telephone poles, and caused considerable localized flooding. The Orange Bowl Stadium, home of the University of Miami’s Hurricanes football team, was heavily damaged when Betsy’s blocking winds overturned bleachers, buckled tower lights, and blew down the marquee. On Florida’s west coast, a transiting Betsy not only devastated large portions of the Big Cypress National Preserve but also spawned a five-foot (2.5-m) storm surge in Everglades City that caused several hundred thousand dollars worth of water damage to posh gulfside villas and yacht-straddled marinas. Three small tornadoes, whistling black funnels that trailed Betsy’s well-organized cloud bands, further augmented the hurricane’s destructive
legacy. Numerous mobile homes in Dade County were violently wrenched from their foundations and then peeled apart panel by panel while a number of vehicles— among them a refrigerated citrus truck—were catapulted through the stormy skies by the tornadoes’ whirring intensity. A total of thirteen people were killed in Florida, nine of them listed as “missing at sea” after Betsy’s tumultuous waves overtook a squadron of fleeing excursion craft near Barnes Key.

Its sustained winds barely weakened by its stunning assault on south Florida, Betsy then spiraled across the Gulf of Mexico during the evening hours of September 8. Forecasters at the National Hurricane Center (NHC) predicted that the hurricane— with rapidly reintensifying winds and a cresting, nine-foot (3-m) storm surge—would make landfall somewhere in the vicinity of New Orleans, Louisiana. Fearing that New Orleans would suffer catastrophic flooding if the raging, fast-moving storm came ashore directly over the low-lying city, authorities began the mass evacuation of some 250,000 people from the Mississippi Delta region. Louisiana’s famed shrimp fleet hauled in its nets, secured its gear, and returned to the crowded safety of its ports, while dozens of oil company personnel stationed on exploratory drilling rigs in the Gulf of Mexico were promptly airlifted to safety.

Bearing a central pressure of 27.99 inches (948 mb), sustained winds of 131 MPH (210 km/h), and drenching rains, Betsy crashed into the coast of Louisiana shortly before midnight on September 9, 1965. The hurricane’s curving track took it ashore 90 miles (145 km) southeast of New Orleans in the vicinity of the Grand Terre Islands, thereby sparing the historic port city the eradicating brunt of its seaborne fury. As it was, Betsy’s fringe winds, measured at 124 MPH (200 km/h), lashed neighborhoods in the western quadrant of New Orleans, causing some damage to chimneys, porches, fences, trees, and telephone poles. Closer to the shore, Betsy’s assault was far more severe: In the Golden Meadows region, more than 27,000 houses were completely destroyed, leaving twice that number of people homeless, more than 2,000 businesses, from farms to factories to shopping centers, were likewise ruined, hindering efforts to provide hurricane victims with vital relief supplies. Sixty-one people in Louisiana were killed. 

In nearby Mississippi, Betsy’s 74-MPH (120-km/h) winds drove an eight to 10-foot (2–3 m) storm surge into Bay St. Louis, washing away entire beaches as it flooded most of the bay’s hurricane-prone north shore; one man was drowned. Quickly moving inland, Betsy brought 99-MPH (160-km/h) winds and two inches (51 mm) of rain to Louisiana’s capital, Baton Rouge, causing isolated power outages and a small ornado. Downgraded to a tropical storm later that evening, Betsy’s lingering winds spawned a further outbreak of tornadoes over Arkansas, killing another four people. By the morning of September 10, Betsy had peeled off to the northeast, crossed into Tennessee, and almost completely dissipated. Remembered as the first “billion dollar” hurricane in U.S. history, Betsy’s rampage through the Bahamas, Florida, and Louisiana claimed 75 lives and left an estimated $1.4 billion dollars in property damage.

Hurricane Betsy of 1965 was not the first tropical cyclone by that name to terrorize the North Atlantic basin. During the first week of August 1956, the first Hurricane Betsy originated over the eastern North Atlantic as a tropical wave before tracking westward to develop into a dreaded Cape Verde system. On August 11, Betsy—now a Category 3 hurricane with sustained wind speeds of 121 MPH (195 km/h)—slid across the northern Leeward Islands, its central barometric pressure of 28.17 inches (954 mb) producing torrential rains and a large storm surge. Weakening as it sliced across the highlands of Puerto Rico and Hispaniola on August 12, Betsy’s 92-MPH (148-km/h) winds downed trees and power lines, while its heavy rains caused many instances of flash flooding. Maintaining its intensity as it recurved to the east of the Bahamas, Betsy followed the circulation patterns of the Bermuda High, and was drawn to the northeast, remaining well off the U.S. eastern seaboard. By August 20, the system had dissipated over the extreme North Atlantic.

It was fortunate that the second Hurricane Betsy remained an offshore tropical system for its entire existence because for a time it was one of the most powerful tropical cyclones yet observed in the North Atlantic basin. Originating south of 15 degrees North on September 2, 1961, Betsy chugged northwestward, steadily growing in severity until September 5, when it achieved Category 4 status. With a central pressure of 27.90 inches (945 mb) and sustained winds of 138 MPH (222 km/h), Betsy tore the surface of the Atlantic into windrows of spray and chased weary shipping from the sea lanes, but caused no damage or loss of life before weakening to Category 3 intensity on September 6. Passing well to the east of Bermuda on September 9, 1961, Betsy rapidly recurved into the North Atlantic and underwent extratropical transitioning by September 12. Following the devastating passage of the third Hurricane Betsy in 1965, the name was struck from the cyclical list of North Atlantic hurricane identifiers.

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