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Hurricane Beulah was the second tropical storm, second hurricane, and only major hurricane during the 1967 Atlantic hurricane season. It tracked through the Caribbean, struck the Yucatán peninsula of Mexico as a major hurricane, and moved west-northwest into the Gulf of Mexico, briefly gaining Category 5 intensity. It was the strongest hurricane during the 1967 Atlantic hurricane season. The hurricane made landfall just north of the mouth of the Rio Grande River as a Category 3. It spawned 115 tornadoes across Texas, which established a new record for the highest amount of tornadoes produced by a tropical cyclone. Due to its slow movement over Texas, Beulah led to significant flooding. At the time, Beulah ranked as the second-costliest hurricane on record, having left roughly $1 billion (1967 USD) in damage. Only Hurricane Betsy two years prior had caused such considerable losses. Throughout its path, at least 688 people were killed. ==Meteorological history== On August 22, 1967, an ESSA-5 satellite image depicted an area of enhanced convection—shower and thunderstorm activity—east of the Western High Plateau in Cameroon over central Africa. Reaching the western slopes of the mountains two days later, the tropical wave became more coherent with clouds condensing along its axis. As it moved over west Africa, cyclonic rotation became apparent about above the surface. A research paper published in 1969 refers to the disturbance as a depression as it neared the west coast of Africa;〔 however, this significantly differs from the official Atlantic hurricane database which does not mention the system at that time, as a surface circulation likely did not exist. Regardless, the system emerged over the Atlantic Ocean around 12°N on August 28, as represented by barometric pressure falls in Dakar, Senegal. Once over water, the system interacted with the Intertropical Convergence Zone and continued westward along an undulating path with no further organization. It was not until a United States Navy weather reconnaissance plane flew into the disturbance on September 4, while it was located east of the Lesser Antilles, that signs of development were apparent. Corresponding observations from ships in the region on September 5 confirmed the existence of a 1010 mbar (hPa; 28.23 inHg) low-pressure area. In light of this, the disturbance was classified as a tropical depression at 12:00 UTC that day, with its center situated roughly 175 mi (285 km) east-northeast of Barbados.〔 A slow-moving system, the depression steadily organized as it approached the Lesser Antilles. Observations from aircraft reconnaissance indicated that the system attained gale-force winds by 12:00 UTC on September 7, resulting in its upgrade to a tropical storm. It was also assigned the name ''Beulah'', making it the second named storm of the 1967 season. Shortly after being named, Beulah clipped the southern coast of Martinique and entered the eastern Caribbean Sea. Feeding off the warm waters of the Caribbean, the cyclone quickly strengthened and reached hurricane intensity by 18:00 UTC on September 8. Rapid deepening ensued thereafter with the storm's central pressure falling to 940 mbar (hPa; 27.75 inHg) the following day as it passed 100 mi (160 km) south of Puerto Rico.〔 At this time winds were estimated to be at least 140 mph (225 km/h), ranking Beulah as a Category 4 on the Saffir–Simpson hurricane scale.〔 Upon reaching this strength, weather radar imagery from San Juan, Puerto Rico showed that Beulah featured a 15 mi (24 km) wide eye surrounded by an intense eyewall about 8 mi (13 km) thick.〔 During the evening of September 9 Beulah turned westward as weak ridge developed over the Bahamas, between it and the newly formed Tropical Storm Doria.〔 The powerful storm weakened somewhat as an eyewall replacement cycle began to take shape. During this phase, the inner-eye of Beulah contracted to roughly 3–4 mi (5–6 km) in diameter while a second eyewall spanned an area 28 mi (45 km) across. The smaller eye soon dissipated and the larger one became the single, dominant feature by the morning of September 10. The completion of this marked the first time that an eyewall replacement cycle was observed in its entirety. The aforementioned westward turn placed the Dominican Republic in the line of danger, an area still reeling from the devastating effects of Hurricane Inez just one year prior. Fortunately, the storm unexpectedly collapsed as it approached the Barahona Peninsula and struck the area as a greatly weakened, though still significant, hurricane with estimated winds of 90 mph (150 km/h) around 18:00 UTC on September 11.〔〔 Skirting the southern coast of Haiti's Tiburon Peninsula, Beulah further degraded to a tropical storm by the morning of September 12. Unseasonably strong wind shear associated with the jet stream, resulting from an upper-level trough to the north, and the cyclone's interaction with land were responsible for the dramatic degradation. By the time it had cleared Haiti, Beulah was no more than a minimal tropical storm with winds near 40 mph (65 km/h).〔 Its pressure had also risen by roughly 60 mbar (hPa; 1.77 inHg) to 1000 mbar (hPa; 29.53 inHg).〔 Originally seen as a threat to Jamaica, northeasterly flow induced a southerly component to the track and pushed the cyclone south of the island on September 13. The shear previously impeding organization abated on September 14 and a ridge re-established itself to Beulah's north, allowing the storm to resume a west-northwest to northwest track. The upper-level changes led to a favorable environment for intensification and Beulah regained hurricane strength by 12:00 UTC on September 14 while located about 425 mi (685 km) south-southeast of Havana, Cuba.〔〔 Moving through the climatologically favorable western Caribbean,〔 Beulah quickly regained major hurricane status on September 15 with winds estimated at 115 mph (185 km/h).〔 The storm's pressure fell to 964 mb (hPa; 28.47 inHg) on September 16 before some weakening took place. Beulah ultimately made landfall on Cozumel island with winds of at least 100 mph (160 km/h) later that day and struck the mainland Yucatán Peninsula hours later. Despite moving over land, little weakening took place by the time the hurricane emerged over the Gulf of Mexico about 24 hours later.〔 The hurricane maintained its intensity throughout September 18 as it moved west-northwest to southern Tamaulipas, Mexico.〔 However, on September 19, a pronounced phase of rapid intensification took place as Beulah turned northwest to the Rio Grande Valley region. Aircraft reconnaissance throughout the day found falling pressures and ultimately measured a value of 923 mbar (hPa; 27.25 inHg) around 18:00 UTC. This was the second-lowest pressure ever recorded by aircraft at the time, behind a 920 mbar (hPa; 27.17 inHg) measurement in Hurricane Hattie of 1961.〔 Beulah was estimated to have achieved its peak intensity shortly thereafter as a Category 5 hurricane with winds estimated at 160 mph (260 km/h).〔 Regarded as the third-largest hurricane on record at the time, Beulah moved along a slowing, erratic, and somewhat cycloidal path. Slight weakening ensued as it neared land and Beulah ultimately made its final landfall south of Brownsville, Texas near the mouth of the Rio Grande River around 13:00 UTC on September 20. No direct measurements exist at the core of the hurricane as it moved ashore; however, based on a minimum pressure of 951 mbar (hPa; 28.09 inHg) in Brownsville, the hurricane likely struck land at an intensity below that value.〔 A vessel anchored in the Port of Brownsville measured peak wind gusts of 136 mph (219 km/h), equivalent to a low-end Category 4 hurricane.〔〔 According to the National Hurricane Center, Beulah struck as a Category 3 and had a pressure of 950 mbar (hPa; 28.05 inHg), though a conclusive estimate awaits re-evaluation as part of the Atlantic hurricane reanalysis project. Once over land, the hurricane slowly weakened as it remained relatively close to the coast. Winds dropped below hurricane-force on September 21, roughly 24 hours after landfall. The system subsequently stalled near Alice, Texas before turning to the southwest.〔 After diminishing to a tropical depression late on September 22,〔 Beulah's circulation finally dissipated over the mountainous terrain of Nuevo León, Mexico.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hurricane Beulah」の詳細全文を読む スポンサード リンク
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