Hurricane Alicia

Hurricane Alicia was a small but powerful tropical cyclone that caused significant destruction in the Greater Houston area of Southeast Texas in August 1983. Although Alicia was a relatively small hurricane, its track over the rapidly growing metropolitan area contributed to its $3 billion damage toll, making it the costliest Atlantic hurricane at the time. Alicia spawned from a disturbance that originated from the tail-end of a cold front over the northern Gulf of Mexico in mid-August 1983. The cyclone was named on August 14 when it became a tropical storm, and the combination of weak steering currents and a conducive environment allowed Alicia to quickly intensify as it drifted slowly westward. On August 17, Alicia became a hurricane and continued to strengthen, topping out as a Category 3 major hurricane as it made landfall on the southwestern end of Galveston Island. Alicia's eye passed just west of Downtown Houston as the system accelerated northwestwards across East Texas; Alicia eventually weakened into a remnant area of low pressure over Oklahoma on August 20 before they were last noted on August 21 over eastern Nebraska.

Alicia was the first hurricane to make landfall on the United States since Hurricane Allen struck South Texas in August 1980 over three years prior, ending the longest period of the twentieth century without a landfalling hurricane on the U.S. coast. Alicia's approach precipitated the evacuation of 60–80 thousand people from coastal communities along the coasts of Southeast Texas and Louisiana. Along the coast, a storm tide flooded communities, with the rough surf sinking several ships and resulting in three offshore fatalities. Most of the damage attributed to the storm was caused by strong winds estimated to have peaked at 130 mph (210 km/h) in southwestern Galveston Island. Alicia was the first major hurricane to form in the Gulf of Mexico since Hurricane Anita of 1977.

Widespread damage was wrought in Galveston and Houston, where thousands of homes were destroyed. In Downtown Houston, nearly all skyscrapers saw the loss of approximately half of lower-level windows, littering the urban streets with debris. Widespread power outages and flooding impacted much of Southeast Texas, with observed rainfall totals peaking at . In addition to the strong winds, rough surf, and heavy rain, Alicia also generated 22 tornadoes centered around the Houston–Galveston area; most were rated F0, but the strongest, an F2, tore through Corsicana farther north.

The impacts of Alicia tapered inland past the point of landfall, though the weakening system still produced damaging winds and flooding in the Dallas–Fort Worth metroplex and Oklahoma; light rain associated with Alicia was observed as far north as Michigan. In total, Alicia caused 21 fatalities and 7,288 casualties; due to the extent of its damage, the name ''Alicia'' was retired by the World Meteorological Organization in 1984.

Meteorological history

The origin of Hurricane Alicia can be traced to a frontal boundary that extended from New England to the Gulf of Mexico. This weak front was initially stationary over the Southeastern United States but moved slowly southward into the north-central and northeastern fringes of the gulf, producing strong convective activity beginning on the night of August 13, 1983."Hurricane Alicia Post Storm Report", p. 1 On August 14, a small area of low pressure developed on the western end of the front and moved off the coasts of Mississippi and Alabama, intensifying as it progressed further into the open gulf waters. The thunderstorms associated with the small low-pressure area—described as a mesoscale convective complex—aided in the development of additional storms in the northern Gulf of Mexico by facilitating favorable conditions for convective initiation. By the evening of August 14, the disturbance had largely separated from the parent frontal trough and continued to organize around a surface-level circulation. A United States Air Force reconnaissance aircraft investigated the precursor system and determined that it had developed into a tropical depression at 12:00  UTC (7:00 a.m. CDT) on August 15 while south of New Orleans, Louisiana. Within six hours of developing, the disturbance intensified further into a tropical storm, attaining the name ''Alicia'' and becoming the hurricane season's first named storm."Hurricane Alicia Post Storm Report", p. 2 Due to Alicia's formation in a region with high environmental pressures, the storm remained relatively small throughout its lifetime. The presence of a ridge of high pressure to Alicia's north steered the nascent tropical cyclone slowly westward in the early part of its development. The ridge eventually drifted eastward, resulting in Alicia slowly curving towards the northwest beginning mid-day on August 16.

The storm's slow movement—averaging just 5 mph (8 km/h)—and lack of strong steering currents allowed Alicia to reap highly favorable conditions characterized by warm sea surface temperatures in excess of and favorable winds in the upper troposphere due to an upper-level anticyclone, resulting in unabated intensification until landfall. Radar analyses indicated that Alicia was stationary at times as it transitioned to a northwesterly heading. An eye began to emerge on satellite imagery by the afternoon of August 16. On August 17, Alicia strengthened into a hurricane with its pressure falling at a steady 1 mbar (hPa; 0.03 inHg) per hour. At 06:00 UTC (1:00 a.m. CDT) on August 18, Alicia became a major hurricane and made landfall an hour later on Galveston Island— southwest of Galveston, Texas—with maximum sustained winds of 115 mph (185 km/h) and a minimum barometric pressure of 962 mbar (hPa; 28.41 inHg) as measured by aircraft reconnaissance, making it a low-end Category 3 on the Saffir–Simpson hurricane wind scale. Alicia was the first hurricane to strike the continental United States since Hurricane Allen moved ashore South Texas in August 1980, ending the longest break in contiguous U.S. hurricane landfalls of the 20th century. The hurricane was also the first major hurricane to impact the Greater Houston area since Hurricane Carla in 1961.

Alicia weakened as it accelerated northwest into the Texas interior, with the hurricane's center passing just west of Downtown Houston on the morning of August 18 as a Category 1 hurricane; the storm was initially slow to weaken as it was able to rein in moist air from the warm Gulf of Mexico. Later that day, the continued inhibitory impacts of friction and dry air weakened Alicia to a tropical storm near College Station, Texas,"Hurricane Alicia Post Storm Report", p. 3 and degenerated into a tropical depression early on August 19 near the Dallas–Fort Worth metroplex. Despite having remained over land for 36 hours, Alicia remained well-organized while tracking into Oklahoma on August 20. The tapering system transitioned into an extratropical cyclone later that day; these remnants persisted for another day before they were absorbed by a passing trough over eastern Nebraska on August 21.

Preparations

Hurricane Alicia marked the first time the National Weather Service provided local interests with landfall probabilities, beginning 60 hours before Alicia's eventual landfall. The new information was generally well received by local officials, though a slight uptick in landfall probabilities for the New Orleans area was interpreted by a local radio station to have denoted a change in Alicia's course, resulting in the unnecessary transition of two local hospitals to emergency operations."Hurricane Alicia Post Storm Report", p. 8 The first gale warnings and hurricane watches were issued for the United States Gulf Coast between Corpus Christi, Texas and Grand Isle, Louisiana at 16:00 UTC (11:00 a.m. CDT) on August 16. Coastal areas from Corpus Christi, Texas, to Morgan City, Louisiana were issued hurricane warnings shortly after Alicia intensified into a hurricane on August 17; these warnings remained until the storm weakened into a tropical storm over East Texas. The National Weather Service office in Galveston suspended operations after water began to flood the office at the height of the storm.

Between 60 and 80 thousand people were evacuated from Brazoria, Chambers, Galveston, and Harris counties in advance of Alicia, as well as 1,500 persons from Sabine Pass. Twenty thousand people sought refuge at shelters within Houston. Another 6,000 evacuated from Cameron Parish, Louisiana. Offshore oil operations were postponed in preparation for Alicia with the evacuation of 1,360 workers, most of whom were from Shell platforms."Hurricane Alicia Post Storm Report", p. 6 Initially, however, residents did not take the warnings seriously. Galveston Mayor E. Gus Manuel, against the advice of Texas Governor Mark White, ordered the evacuation of only low-lying areas. As a result, only 10 percent of the population living behind the seawall chose to leave when Alicia came ashore. In contrast, about 30 percent of Galveston's population evacuated the island when Hurricane Allen threatened the eastern Texas coastline in 1980.
Throughout the day, however, as the increasing winds began to cause damage in Galveston, people grew more concerned. The mayor finally ordered a widespread evacuation of the island after midnight on August 18, but by then, the bridges to the mainland were uncrossable.

Impact

Hurricane Alicia caused US$3 billion in damage, making it the costliest tropical cyclone in U.S. history at the time; insured losses were estimated at US$700 million by the American Insurance Association. There were 7,288 casualties, including 21 fatalities and 25 hospitalizations. Despite being a relatively small and low-end Category 3 hurricane, the impacts of Alicia were exacerbated in the Houston metropolitan area due to a rapid increase in population, resulting in a rise in potentially susceptible infrastructure that also induced as much as in land subsidence along some stretches of Galveston Bay."Hurricane Alicia Post Storm Report", p. 5

Texas

Houston and Galveston areas

Alicia produced a storm tide that crested along the interior coast of Galveston Bay near Baytown, Texas. A 300-home subdivision near Baytown sustained extensive damage to most dwellings. Seabrook, Texas also documented a storm tide, with slightly lower tide heights of occurring at the Flagship Hotel in Galveston."Hurricane Alicia Post Storm Report", p. 4 The rough surf eroded as much as of beach in western parts of Galveston Island. A recently constructed levee system protecting Texas City mitigated potential storm surge data to the city's extensive industrial infrastructure. However, an oil spill resulting from a ruptured tank near Galveston Bay swept through areas near the Texas City Dike

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