Hurricane Opal

Category 4 major hurricane (SSHWS/NWS)
Hurricane Opal approaching major hurricane status in the Gulf of Mexico on October 3
Formed	September 27, 1995 (September 27, 1995)
Dissipated	October 6, 1995 (October 6, 1995)
( Extratropical after October 5)
Highest winds	1-minute sustained: 150 mph (240 km/h) [nb 1]
Lowest pressure	916 mbar ( hPa); 27.05 inHg
Fatalities	63 total
Damage	$5.1 billion (1995 USD)
Areas affected	Guatemala Yucatán Peninsula U.S. Gulf Coast (particularly the Florida panhandle) Eastern United States Eastern Canada
Part of the 1995 Atlantic hurricane season

Hurricane Opal was an intense and destructive late-season tropical cyclone that impacted the United States Gulf Coast and Yucatán Peninsula from late September to early October 1995. As part of a highly active hurricane season, the storm was also the first Atlantic cyclone to be given a name starting with the letter "o." At the time, the hurricane was the third costliest Atlantic hurricane on record behind only hurricanes Andrew and Hugo Opal's slow movement and copious rainfall contributed to its impacts in Mexico and Guatemala, where most of the deaths associated with the storm occurred, while strong winds and high storm surge were the cause for most of the damage along the United States Gulf Coast, where most of Opal's damage toll monetarily was accrued. Lesser impacts were felt across the Eastern United States and into Eastern Canada, where the storm produced a wide swath of heavy rain, strong gales, and tornadoes.

Opal originated from a tropical depression on September 27 off the Yucatán Peninsula; the system reached tropical storm intensity despite interacting with peninsula on September 30 before becoming a hurricane in the Bay of Campeche on October 1. Rapid intensification ensued after Opal turned northeast as the storm moved over the Gulf of Mexico, reaching Category 4 hurricane strength on October 4 before steadily weakening thereafter. Later that day, Opal made landfall on the extreme northwestern Florida coast. Continued progress into the North American continent caused the system to quickly weaken over land; on October 6, the once potent system had transitioned into an extratropical cyclone before dissipating later that day.

Meteorological history

The origins of Hurricane Opal were linked using satellite imagery and synoptic analyses to a tropical wave that departed the western coast of Africa on September 11. ^[1] Ten days later, the disturbance had crossed the central Atlantic and had reached the Lesser Antilles. ^[2] Continuing to track westward, the disturbance showed little signs of organization before entering the western Caribbean Sea on September 23. There, the wave became entangled with a broad area of low-pressure east of Nicaragua, and the combined system drifted west-northwestward towards the Yucatán Peninsula. Even then, the disturbance lacked any significant development. However, a burst of thunderstorm activity occurred near the storm's center on September 27, prompting the National Hurricane Center (NHC) to declare the system a tropical depression at 18:00  UTC that day. At the time, the depression was centered 80 mi (130 km) south-southeast of Cozumel, Mexico. ^[1]

The primordial depression meandered across the Yucatán Peninsula during the three days following tropical cyclogenesis due to the lack of dominant steering currents. Despite remaining over land for an extended period of time, the depression developed organized rainbands, and ships in the region reported weather conditions that were suggestive of a stronger system. As a result, the NHC upgraded the disturbance to tropical storm intensity at 12:00 UTC on September 30 while the storm was over the north-central coast of Yucatán; this classification resulted in the tropical cyclone being named Opal, which also made it the first Atlantic storm to be given a name starting with the letter "o." ^[3] Over the next two days, Opal would enter the Gulf of Mexico and track slowly west-southwestward into the Bay of Campeche. There, the storm strengthened into a hurricane at 12:00 UTC on October 2. Shortly afterwards, a primitive eye began to form. At the same time, a strong trough tracking across the United States caused Opal to slowly turn northeastward. ^[1]

After clearing the Bay of Campeche, Opal accelerated towards the United States Gulf Coast. The combination of warm sea surface temperatures associated with an unusually warm pocket of warm ocean waters and an upper-level high pressure area over the Gulf of Mexico resulted in a highly conductive environment for intensification. ^{[1] [4]} After a significant reorganization in Opal's internal structure, the hurricane was able to rapidly intensify in these favorable conditions. At 12:00 UTC on October 4, Opal reached peak intensity with maximum sustained winds of 150 mph (240 km/h) and a minimum barometric pressure of ( hPa; 27.05  inHg), making it a Category 4 on the Saffir–Simpson hurricane wind scale. The tropical cyclone's eye measured 12 mi (19 km) at peak intensity as the storm was beginning an eyewall replacement cycle. The progression of this cycle resulted in Opal's gradual weakening thereafter. At 22:00 UTC that day, Opal made landfall between Pensacola Beach, Florida and Cape San Blas as a Category 3 hurricane with winds of 115 mph (185 km/h). Weakening quickened as Opal moved further inland, degenerating into a tropical depression over Tennessee less than a day after landfall. The diffusing cyclone transitioned into an extratropical cyclone shortly afterwards; these extratropical remnants tracked towards the northeast before they were last noted along the northern coast of Lake Ontario in Quebec. ^[1]

Preparations

Although Opal was a weak system located over the Yucatán Peninsula at the time, 350 people evacuated from Grand Isle, Louisiana on September 28 after rough surf associated with the distant cyclone began to threaten Louisiana Highway 1—the only thoroughfare connecting Grand Isle with the Louisianan mainland. ^[5] The following day, oil companies operating offshore oil drilling platforms in the Gulf of Mexico began evacuating workers from the rigs to land. ^[6] On October 1, a coastal flood watch was issued for portions of the United States Coast due to the risk of storm surge from Opal. The United States Coast Guard issued an advisory for boaters in the Gulf of Mexico to use caution or remain in port where possible. The next day, the Galveston, Texas emergency operations center opened in order to monitor the tropical cyclone and deliberate upon potential preparations for the city. ^[7] Meanwhile, the launch Space Shuttle Columbia's STS-73 mission set for October 5 was postponed due to Opal's anticipated effects. ^[8]

On October 3, a voluntary evacuation order was placed on Plaquemines Parish, Louisiana due to the risks of potential storm surge. Schools were also closed by noon that day across the parish. ^[9] Voluntary evacuation orders for the Florida panhandle, which would ultimately be the most heavily impacted area, also began the same day with several counties giving evacuation orders. Further west, a mandatory evacuation order was placed on Mobile County, Alabama by then- Governor Fob James. Just before noon on October 4 with the hurricane near landfall, Escambia, Okaloosa, and Santa Rosa counties halted evacuations, instead ordering those still within vulnerable areas to seek shelter instead. However, the large amount of evacuees led to severe traffic congestion; Escambia County officials estimated that "tens of thousands" were still on evacuation routes within the county only a few hours before Opal made landfall. Mass evacuations in some other counties concluded during the afternoon of October 4, though many evacuees in other locations were unable to reach safe areas prior to the onset of gale-force winds. ^[10]

An estimated 100,000 people evacuated from the United States Gulf Coast ahead of Opal, with 5% of evacuees seeking public shelters and over half of evacuees seeking shelter out of their home counties; in their post-storm assessment the Federal Emergency Management Agency (FEMA) noted that the landfalls of Hurricane Allison and Hurricane Erin on the Florida panhandle earlier in the year produced a dichotomous mood towards preparations for Hurricane Opal—some people may have taken a "wait and see" approach that resulted in complacency, while others impacted by the widespread power outages caused by Erin may have acquired a greater sense of readiness towards the approaching hurricane. Regardless, the overall evacuation process was described as chaotic, and the failure to clear hurricane evacuation routes of casual or communal traffic was blamed for the relative unease during evacuations for Opal. Traffic congestion on these routes caused some evacuees to return to vulnerable areas along the coast while raising fears that stranded evacuees on highways could be subjected to potentially fatal hurricane-force winds. ^[10]

Tropical cyclone watches and warnings

Impact

Mexico and Central America

A slow moving storm early in its existence, ^[1] Opal brought heavy rains to large portions of Mexico and Central America. Across Mexico, the flooding that resulted from the copious precipitation forced the evacuation of 100,000 people, with 20,000 evacuees coming from the state of Campeche where five persons drowned. In Tabasco, rains from Opal over a four day period amounted to 20% of the state's average annual rainfall, inundated 400 communities, and killed two people. Off the Mexican coast in the Gulf of Mexico, the tropical cyclone caused 12 ft (3.7 m) high waves forced the closure of several fishing ports. Some airports were also closed during the storm. ^[6]

U.S. Gulf Coast

Florida

Southeastern United States

Central United States

Northeastern United States

Canada

Aftermath

See also

• Hurricane Eloise – Hurricane that brought extensive damage to the Florida Panhandle; Eloise was the last major hurricane for the Florida Panhandle until Opal
• Hurricane Frederic – One of the costliest Atlantic hurricanes on record, striking similar areas of the U.S. Gulf Coast
• Hurricane Elena – Erratic tropical cyclone that caused widespread damage to the coasts of northwestern Florida despite never making landfall there

Notes

References

External links

Wikimedia Commons has media related to TheAustinMan/sandbox/Hurricane Opal.

Opal Opal 1995 Opal Opal 1995 Opal 1995 Opal 1995 Opal 1995 Opal 1995 Opal 1995 Category:1995 natural disasters in the United States Category:1995 in Guatemala Category:1995 in Mexico Category:History of Atlanta Category:1995 in Florida Category:1995 in Georgia (U.S. state) Category:1995 in Tennessee