Hurricane Irene produced somewhat heavy damage across southern Florida in October 1999. The ninth named storm and the sixth hurricane of the season, Irene developed in the western Caribbean Sea on October 13 from a tropical wave. It moved northward, hitting western Cuba before attaining hurricane status. Irene struck Florida on October 15 as a Category 1 on the Saffir–Simpson Hurricane Scale, first at Key West and later near Cape Sable. The storm moved across the state and tracked northward over the Gulf Stream. It approached the Carolinas but remained offshore. Irene turned eastward and significantly intensified into a strong Category 2 hurricane on October 18. By the following day, the system became extratropical due to cooler waters to the southeast of Newfoundland and was quickly absorbed by another extratropical low.
The hurricane first produced heavy rainfall across western Cuba, causing four deaths and damage. Irene was a wet Florida hurricane in October, similar to many hurricanes of the 1930s and 1940s. It later dropped 10 to 20 inches (254 to 508 millimetres) of rainfall in the Miami metropolitan area, causing urban flooding unseen since Hurricane Dennis in 1981. Despite being only a Category 1 hurricane, Irene caused eight indirect deaths and $800 million (1999 USD) in damage across Florida. The hurricane produced flooding and caused one death in the northwestern Bahamas. In North Carolina and Virginia, Irene produced over 10 inches (250 mm) of rain, adding more flooding after previous hurricanes Dennis and Floyd. The flooding closed many roads and caused rivers to crest past their banks, though the damage in the area was relatively minor.
Meteorological history
A broad area of low pressure formed over the western Caribbean Sea on October 8, and it persisted until October 11, when a tropical wave reached the area and caused the convection to organize, resulting in the development of a low-level circulation. Convection increased and organized around the circulation center late on October 12, and the system organized into Tropical Depression Thirteen at 06:00 UTC on October 13 off the north coast of Honduras. The depression strengthened further over the favorable conditions present in the Caribbean Sea, and attained tropical storm status six hours later, when it was assigned the name Irene. Operationally, the National Hurricane Center (NHC) continued to classify the system as a low-pressure area until 15:00 UTC on October 13, by which time it had already reached tropical storm status.
Tropical Storm Irene strengthened as it moved northward and reached sustained winds of 70 mph (110 km/h) early on October 14. The NHC operationally upgraded Irene to a hurricane on October 14, although later analysis after the hurricane season, including an examination of satellite imagery and observations from weather stations in Cuba, indicated it remained a tropical storm until later. Irene continued to move towards the north-northeast, crossed over the western portion of the Isla de la Juventud as a strong tropical storm, and around 19:00 UTC, it struck mainland Cuba near Batabanó in Mayabeque Province. The cyclone emerged into the Straits of Florida several hours later and resumed intensification, and Irene attained hurricane status early on October 15. It passed over Key West around 13:00 UTC, turned more to the north-northeast, and struck mainland Florida at Cape Sable as an 80 mph (130 km/h) hurricane around 20:00 UTC. Despite Irene strengthening prior to landfall in the state, wind shear caused deep convection to remain mostly displaced to the storm's east side in a semicircular pattern around the center. However, as the hurricane moved northeastward across southeast Florida, deep convection noticeably shifted farther west, likely as a result of a westward movement of the low-level convergence zone due to increased friction. The convergence zone's shift also caused Irene's eye to become better defined.
Irene entered the Atlantic Ocean near Jupiter, Florida, early on October 16, still as a Category 1 hurricane. It turned to the north, remained a hurricane despite little convection, then turned to the northeast in response to an approaching upper-level trough. Just offshore, Irene moved parallel to the coastlines of South Carolina and North Carolina on October 17. While interacting with very warm ocean waters and the upper-level trough on the following day, Irene rapidly intensified, reaching maximum sustained winds of 110 mph (180 km/h) with a minimum barometric pressure of 958 mbar (28.3 inHg), a Category 2 hurricane, at 07:56 UTC. Despite its strength, the circulation was very asymmetrical, and the convection was not particularly organized. The hurricane continued to accelerate to the northeast, steadily weakening until becoming extratropical early on October 19 to the south of Newfoundland. However, the upper-level trough, its associated upper-level jet streak, and warm air advected from the storm resulted in a baroclinic effect, allowing Irene to maintain much of its convection during and following its extratropical transition in spite of decreasing sea surface temperatures. The extratropical storm continued to the northeast until becoming absorbed by another, larger extratropical storm late on October 19.
Preparations
In Cuba, slightly over 228,000 residents were evacuated from low-lying areas before the storm. Around 10% stayed in temporary shelters, while the rest stayed with family or friends. Included in the evacuation total were 6,000 tourists and over 1,000 residents in rickety houses. Workers protected tobacco leaves by moving them to sealed warehouses, and transported cattle and livestock to higher ground. The hurricane forced the closure of schools and the cancellation of some flights. The Cuban government issued a hurricane watch for Pinar del Río Province, Havana, Havana Province, and Isla de la Juventud 21 hours before Irene hit. These areas, along with Matanzas Province, were upgraded to a hurricane warning 15 hours before Irene hit the area.
Initially, forecasters predicted Irene to parallel the west coast of Florida, weakening to a tropical storm before making landfall on the west-central portion of the state. However, when a more eastward track became evident, officials in Monroe, Charlotte, Lee, and Manatee Counties issued evacuation orders for people in mobile homes and recreational vehicles. In addition, Key West issued a curfew during the storm's onslaught. The National Hurricane Center issued a hurricane warning from Florida City around the Florida Peninsula to Boca Grande, including all the Florida Keys and the Dry Tortugas. A tropical storm warning was also issued from Florida City northward to Savannah, Georgia. In addition, the majority of flights during Irene's passage were cancelled in Miami International Airport. Governor Jeb Bush declared a state of emergency on Florida the day before Irene made landfall, and ordered for the activation of the Florida National Guard to aid in disaster efforts.
While moving northward off the coast of Florida, Irene was initially expected to make landfall along the South Carolina coastline, prompting the National Hurricane Center to issue a hurricane warning from Edisto Beach, South Carolina to Cape Hatteras, North Carolina. Because of this, voluntary evacuation orders were issued for portions of South Carolina. However, when the track shifted further to the east, mandatory evacuation orders were issued for coastal areas of North Carolina, with tens of thousands removed from their homes. The evacuation order included several beach towns; those living in low-lying areas and mobile homes were advised to seek shelter. In addition, many of those left homeless from Hurricane Floyd's passage just weeks before were evacuated to shelters. Jim Hunt, the Governor of North Carolina, declared a state of emergency, with the state's emergency management team switching from a recovery objective towards a preparations mission.
Impact
Cuba
While crossing Cuba, Irene produced heavy rainfall, totaling as high as 35.6 inches (900 mm) in Manaca-Iznaga. Further, at least 10.7 inches (270 mm) of rain was noted at Playa Girón in Matanzas Province, while many other locations reported more than 7 inches (178 mm). The Casablanca section of Havana also observed 4.8 inches (120 mm) of precipitation and a peak wind gust of 78 mph (126 km/h). Abnormally high tides generated by the storm overtopped the Malecón seawall in Havana, inundating nearby low-lying areas and prompting the evacuation of several hundred people.
The flooding caused by Irene damaged more than 471,000 acres (1,910 km2) of sugar cane and 39,000 acres (160 km2) of banana plantations. Irene's rainfall also flooded tobacco fields. Throughout the country, Irene's rainfall damaged 27,336 houses and caused the total loss of 730. At least one-third of the city of Havana lost electricity. In all, four people were killed by the storm in Cuba, two of whom in Havana due to electrocution.
Florida
While moving through the Florida Keys, Irene produced a storm surge of up to 2.3 feet (0.70 m) in Key Vaca, while Key West reported a surge of 1.5 feet (0.46 m). The hurricane produced sustained winds peaking at 79 mph (127 km/h); it also produced strong gusts, the strongest of which was clocked at 102 mph (164 km/h) at Big Pine Key. Irene produced heavy rainfall in the Keys, including 12 inches (300 mm) of rain in Key West. The rainfall flooded roads throughout the Keys, prompting officials to close 50 miles (80 km) of U.S. Highway 1. Irene spawned a tornado in Islamorada, causing heavy damage to three houses. Moderate wind gusts caused power outages throughout the Keys, but damage was overall minor. Overall, Irene left 81 homes uninhabitable in Monroe County.
Because Irene continued northeastward after making landfall at Cape Sable, Southwest Florida reported little impact, mostly limited to a few downed trees, palm frons, and power lines in Collier and Lee counties. In Everglades City, however, a seafood store lost its entire roof. Despite moving across the state as a minimal hurricane, there were no observations of sustained hurricane-force winds on mainland Florida. The highest official recorded wind report was 60 mph (97 km/h) in Miami Beach, while the highest accurate wind gust was 71 mph (114 km/h) in Vero Beach. In addition to the National Weather Service Reports, the South Florida Water Management District reported higher wind gusts near Lake Okeechobee of up to 93 mph (150 km/h) in Belle Glade, though these were likely caused by small-scale meso-cyclone-induced downbursts. Irene produced heavy rainfall across southeastern Florida, peaking at 17.45 inches (443 mm) at Boynton Beach, though many areas in the Miami metropolitan area received from 10 to 15 inches (254 to 381 millimetres). One F1 and three F0 tornadoes touched down in Broward and Palm Beach counties, injuring three people.
Strong wind gusts left 700,000 people without power from Miami to West Palm Beach, including the National Hurricane Center. The center briefly lost power, but during an hour and a half delay to reboot the computers, they obtained information from computers in the Mid-West and Washington, D.C. Officials from the Florida Power & Light Company were unable to repair power lines due to strong wind gusts, while Irene's flooding submerged underground lines, preventing repairs until the waters subsided. Five people, including three in one family, were killed when they walked through electrified waters due to downed power lines. The rains from Irene flooded roads and canals, stalling numerous cars. Three people drowned when they drove their vehicles into the canals. The floodwaters persisted for nearly a week in areas, displacing hundreds from their homes and isolating thousands. Property damage in southeastern Florida added up to $262 million, which included damage to approximately 1,200 homes in Broward County and 879 in Miami-Dade County. The storm also demolished or nearly demolished 225 residences in Palm Beach County.
Additionally, Irene caused severe agricultural damage in southeastern Florida adding up to $338 million, approximately $75 million of which occurred to crops alone in Miami-Dade County. Impacts to crops and farming also accounted for the vast majority of Palm Beach County's overall damage total of about $100 million. Floodwaters killed 30 cattle at one farm, though the owners protected the rest of their 1,700 cattle by raising the feeding areas above the flood plain. According to an initial estimate, the flooding destroyed between 5% and 15% of fruit groves along its path. The flooding delayed the winter planting of corn and bell peppers and damaged tomato plants, forcing Miami-Dade County growers to replant damaged crops. The hurricane also damaged sugar cane, vegetables, and citrus crops, with citrus canker spreading after the storm passed through the area. A U.S. Sugar processing mill in Bryant suffered about $4 million in damage after winds demolished two cooling towers and toppled some of the facility's walls. The company also lost around 500,000 boxes worth of oranges, equivalent to roughly 90% of its orange crops.