1999 Atlantic hurricane season

The 1999 Atlantic hurricane season was a very active, destructive and deadly season in which 16 tropical cyclones formed. Among them, 12 became named storms, of which 8 became hurricanes. Five hurricanes intensified further into major hurricanes. The season featured a record-tying five Category 4 hurricanes. This high activity is mostly due to a persistent La Niña that developed in the latter half of the previous year. The season officially began on June 1, and ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. The first storm, Arlene, formed on June 11 to the southeast of Bermuda. It meandered slowly for a week and caused no impact on land. Other tropical cyclones that did not affect land were Hurricane Cindy, Tropical Storm Emily, and Tropical Depression Twelve. Localized or otherwise minor damage occurred from Hurricanes Bret, Gert, and Jose, and tropical storms Harvey and Katrina.

The most significant storm of the season was Hurricane Floyd, a strong Category 4 hurricane that caused devastating flooding along the East Coast of the United States, especially in North Carolina. Damage from the storm totaled approximately $6.5 billion (1999 USD) and there were at least 77 fatalities, making it the deadliest hurricane in the United States since Hurricane Agnes in 1972. Flooding from Floyd in North Carolina followed Hurricane Dennis, a slow and erratic–moving storm that dropped heavy rainfall in the eastern portion of the state. Tropical Depression Eleven in October contributed to extreme flooding in Mexico, which left 636 people dead and caused $491.3 million in damage, though impact could not be distinguished from the storm itself. Hurricane Irene caused extensive flooding in Cuba and Florida, with lesser effects in the Bahamas and North Carolina. Irene was the second–costliest storm of the season, with about $800 million in damage. Hurricane Lenny was an unusual eastward–moving storm in the Caribbean Sea and a strong late–season storm. It caused extensive damage in the Lesser Antilles in the month of November. Collectively, the storms of the 1999 Atlantic hurricane season caused at least 775 fatalities and $8.78 billion in losses.

Seasonal forecasts

{| class="toccolours" cellspacing=0 cellpadding=3 style="float:right; margin-left:1em; text-align:right; clear: right;"

|+Predictions of tropical activity in the 1999 season

|- style="background:#CFCFCF; text-align:center;×÷≥"

|align="center"|Source

|align="center"|Date

|align="center"|Named storms

|align="center"|Hurricanes

|align="center"|Major hurricanes

|align="center"|Ref

|align="center" colspan="2"|Average (1981–2010) || 12.1 || 6.4 || 2.7 ||

|align="center" colspan="2"|Record high activity

|30

|15

|7†

|align="center" colspan="2"|Record low activity

|0†

|align="left"|WRC

|align="left"|Early 1999

|10

|N/A

|align="left"|CSU

|align="left"|April 7, 1999

|14

|align="left"|CSU

|align="left"|June 4, 1999

|14

| Early in 1999, WRC issued its forecast for the season, projecting ten named storms and six hurricanes, but no prediction on the number of major hurricanes. In their outlook on May 27, experts at NOAA noted that an above average season was a strong possibility. An addition to a La Niña, vertical wind shear would be decreased across much of the Caribbean Sea and tropical Atlantic Ocean, and a favorable jet pattern for tropical waves to develop into tropical cyclones. On June 1, TSR predicted that there would be 12 named storms, 7 hurricanes, and 2 major hurricanes.

Seasonal summary

thumb|right|250px|Hurricanes [[Hurricane Floyd|Floyd (left) and Gert (right) pictured on September 13]]

The Atlantic hurricane season officially began on June 1, 1999, later tied again in 2005 and 2020. These were Bret, Cindy, Floyd, Gert, and Hurricane Lenny. Between August and October, there was very low wind shear over the Caribbean Sea and western Atlantic Ocean, attributed to a combination of abnormal upper-level easterly winds and low-level westerly winds. Six hurricanes and two tropical storms made landfall during the season and caused at least 123 deaths and approximately $8.19 billion in damage. Hurricane Gert also caused damage and fatalities, despite not making landfall.

Overall, the season's activity was reflected with a high cumulative accumulated cyclone energy (ACE) rating of 177. ACE is, broadly speaking, a measure of the power of the hurricane multiplied by the length of time it existed, so storms that last a long time, as well as particularly strong hurricanes, have high ACEs. It is only calculated for full advisories on tropical systems at or exceeding or tropical storm strength.

Systems

Tropical Storm Arlene

Along a diffuse front, a broad area of low pressure in association with an upper-level low was noted several hundred miles northeast of Puerto Rico on June 8. After the circulation reformed within the area of stronger convection, the NHC estimated that Tropical Depression One developed at 18:00 UTC on June 11 about southeast of Bermuda. Initially, the system resembled a subtropical cyclone, due to its frontal characteristics. The nascent depression drifted northward for 24 hours, and during this time, it strengthened and was upgraded to Tropical Storm Arlene at 12:00 UTC on June 12, based on Dvorak satellite classifications. The storm intensified further to its peak intensity at 00:00 UTC on June 13, with estimated maximum sustained winds of and a minimum barometric pressure of , based on ship reports and satellite. Subsequently, weakening due to westerly wind shear, Arlene tracking westward on June 13 and turned northwest the following day. Because the steering current became poorly defined, it drifted starting on June 15, and executed a small cyclonic loop later that day. At 00:00 UTC on June 17, Arlene was downgraded to a tropical depression. Later that day, it passed about east of Bermuda, where gale-force winds and abnormally high tides were observed. The depression weakened further due to decreasing sea surface temperatures and dissipated early on June 18. The depression dropped heavy rain on the area amounting to a maximum of at Tanzabaca, San Luis Potosí. In some areas, up to of precipitation fell in 24 hours.

Bret was a small tropical cyclone that made landfall in a sparsely–populated region of Texas, resulting in relatively little damage. Strong winds left approximately 64,000 people without electricity in South Texas. Four people died after a truck and a tractor collided near Laredo due to slick roads. In Mexico, the storm brought flooding to Coahuila, Nuevo Leon, and Tamaulipas, with an estimated of rain falling in Nuevo Leon. Three people died in Mexico – one was trampled to death during evacuation, another was electrocuted, and the third drowned. Overall, the storm caused $15 million in damage.

Hurricane Cindy

On August 18, a tropical wave moved westward off the coast of Africa. With low pressures and gradually organizing convection, Tropical Depression Four developed west of Senegal early on August 19. Initially it failed to intensify due to wind shear, After passing south of Cape Verde, the depression intensified into Tropical Storm Cindy as the convection became concentrated around the center. Due to a strong ridge, Cindy moved westward, before turning northwestward by August 21. Banding features gradually increased as outflow improved, and late on August 21, Cindy became a hurricane. Afterward, increased wind shear dislocated the convection from the center, which weakened Cindy to a tropical storm.

By August 23, high wind shear remained, and the storm's winds decreased to . The shear decreased on August 24, By late on August 25, Cindy regained hurricane status. and early the next day it attained major hurricane status. Cindy turned north-northwestward, now showing a well-defined eye, Turning northward, the storm remained at peak intensity until August 30, when prominent wind shear weakened Cindy again. and later that day it merged with a large extratropical storm northwest of the Azores.

In the Bahamas, Dennis produced moderate winds, rain, and storm surge on San Salvador, Crooked Island, Eleuthera, and Abaco Islands, resulting in damage to roofs and coastal properties. Dennis brought waves to the east coast of Florida, causing minor erosion and four drowning deaths. The waves left severe erosion and coastal flooding along the Outer Banks of North Carolina. In Carteret, Craven, and Dare counties, the storm damaged at least 2,025 homes and businesses to some degree. Heavy rainfall, peaking at at Ocracoke, fell in eastern North Carolina. Although the precipitation was generally beneficial due to drought conditions, it also damaged crops. Similar inland flooding occurred in northern and eastern Virginia, The NHC did not initiate advisories until 2100 UTC, when a reconnaissance aircraft observed winds of in association with the small circulation of Emily. The agency initially predicted that the storm would intensify into a hurricane near the Windward Islands. Increased wind shear generated by Hurricane Cindy caused Emily to weaken slightly on August 25. Emily began moving slowly northwestward and progressively became more influenced by Cindy, developing occasional convective bursts. Later on August 26, the movement turned northward, well offshore the Lesser Antilles. Eventually, the storm no longer produced convective bursts, and by 12:00 UTC on August 28, Emily weakened to a tropical depression. Six hours later, the storm was absorbed into Cindy northeast of the Leeward Islands. Shortly thereafter, the center of circulation of the depression became difficult to locate, but was likely heading north-northwestward. Due to warm ocean temperatures, the SHIPS model predicted further intensification, despite the storm having almost no deep convection and being close to land.

At 12:00 UTC on September 6, the depression made landfall near La Pesca, Tamaulipas, with winds of . The depression quickly weakened inland, and dissipated about twenty-four hours after landfall. Due to forecasts that the depression would strengthen to a tropical storm, the government of Mexico issued a tropical storm warning for Tampico to Matamoros, Tamaulipas.

Hurricane Floyd

A westward moving tropical wave developed into a tropical depression while located about east of the Lesser Antilles on September 7. The depression strengthened and was upgraded to Tropical Storm Floyd on the following day. Floyd became a hurricane on September 10, while curving northwestward, before the storm resumed its initial west-northwestward course late on the following day. Significant intensification occurred on September 12 and September 13. At 12:00 UTC on the latter date, Floyd peaked with maximum sustained winds of and a minimum barometric pressure of . Thereafter, the storm began weakening while approaching the Bahamas, decreasing to Category 3 intensity at 06:00 UTC on September 14. Six hours later, Floyd made landfall near Alice Town on Eleuthera with winds of , around the time that the cyclone began moving north-northwestward. Shortly before striking the Abaco Islands at 19:00 UTC, the hurricane re-intensified into a Category 4 hurricane. Early on September 15, Floyd weakened to a Category 3 hurricane and passed offshore Florida. Floyd weakened to a Category 2 hurricane late on September 15, while re-curving to the north-northeast. At 16:30 UTC on September 16, Floyd made landfall near Cape Fear, North Carolina, with winds of . Thereafter, the storm rapidly weakened and was a tropical storm by early on the following day. Floyd moved along the coasts of the Delmarva Peninsula and New Jersey, before striking Long Island in New York early on September 17. Shortly thereafter, Floyd transitioned into an extratropical cyclone while interacting with a frontal zone over Maine.

In the Bahamas, a combination of strong winds and storm surge destroyed numerous restaurants, hotels, shops, and homes, and left tens of thousands without water, electricity, and food. One death was reported. Although millions of people in Florida evacuated, damage was relatively minor.

Flooding in Virginia damaged about 182 businesses and 9,250 houses, and left about of standing water in Franklin. There were three deaths and $101 million in losses. In Maryland, flooding damaged at least 694 homes, impacted numerous bridges and roads, and left over 250,000 residents without power. Similar effects occurred in Delaware, with at least 171 houses damaged and numerous roads being inundated or washed out. In New York City, Floyd dropped of rainfall at the Central Park observatory, setting a daily record for precipitation on September 16. Overall, Floyd caused about $6.5 billion in damage and 73 fatalities. After increases in intensity, banding features, and outflow improvement, the depression was upgraded to Tropical Storm Gert on September 12. Early on September 15, Gert attained major hurricane strength, as it developed well-defined outflow around a central dense overcast. Early on September 16, Gert reached peak winds of and a minimum barometric pressure of , based on satellite-estimates. This made Gert a Category 4 hurricane. At the time, it was located about 720 mi (1160 km) east-northeast of Guadeloupe in the Lesser Antilles. but Gert re-strengthened to a Category 4 hurricane on September 19. That day, the hurricane passed about east of Bermuda. Gert weakened to a tropical storm on September 23 after convection decreased around the center. About six hours later, the remnants of Gert were absorbed by a larger extratropical storm. Wind gusts on Bermuda reached , while sustained winds peaked at 80 mph (130 km/h). Gert also dropped light rainfall of around . Approximately 12,000 residents temporarily lost power. Several roads were flooded, and the intense winds downed trees. In Maine, a rogue wave generated by Gert killed two people at Acadia National Park after sweeping them out to sea. Along the coast of Newfoundland, Gert produced wave heights of 30 ft (9 m). In St. Bride's along the Avalon Peninsula, a large wave severely damaged a wharf, destroying five boats and damaging 45 others. The wave swept three people into the ocean, hospitalizing one of them. The wharf required $2 million (1999 CAD, $1.9 million 1999 USD) in repairs, forcing its closure. Further west, high waves damaged a fish plant in Lord's Cove. Gale-force winds extended across southeastern Newfoundland. The remnants reached Atlantic Canada before dissipating on September 24. as well as two tornadoes, neither of which caused left severe impact. Damage estimates in Florida reached about $15 million.

Tropical Depression Eleven

Until a westward moving tropical wave reached the western Caribbean Sea on September 30, minimal organization occurred. The system eventually emerged into the Gulf of Mexico and developed into Tropical Depression Eleven on October 4. Weak steering current caused the depression to drift slowly and erratically, with the depression initially heading southward, before curving northwest. A surface trough over the central and eastern Gulf of Mexico prevented significant strengthening. The depression remained below tropical storm intensity, attaining its peak intensity on October 5, with maximum sustained winds of and a minimum barometric pressure of . While approaching the Gulf Coast of Mexico, the depression was absorbed by the surface trough at 18:00 UTC on October 6. Throughout Mexico, 90,000 houses were damaged or destroyed, leaving about 500,000 people homeless. and more than 400 people dead.

Flooding caused thousands of landslides and 39 rivers to overflow, leading to the destruction of bridges, houses, widespread crop fields, schools, and electrical networks. Flooding also extended into Central America in late September through early October, causing $40 million (385 million pesos) in crop damage and 70 deaths. However, impact by the depression itself cannot be distinguished. Due to an anticyclone, conditions appeared favorable for significant strengthening, with the National Hurricane Center predicting the depression to be at least a strong tropical storm by October 9. However, wind shear began undercutting the anticyclone, which prevented any significant intensification. The depression never re-organized and instead deteriorated in structure due to shearing. Despite a burst in convection on October 8, the depression dissipated at 18:00 UTC while located about east-northeast of Barbuda.

Irene dropped heavy rainfall throughout its path, especially in Cuba and Florida. Rainfall on Cuba peaked at in Manaca-Iznaga, while the rest of the island reported more than . Hurricane forces winds were also reported in Havana. The storm brought flooding to Florida, particularly the southern portion of the state, where of rain fell in Boynton Beach. Hundreds were displaced from their homes and thousands were isolated. Five people died from walking through electrified water after a power line fell, while three others drowned after unintentionally driving their vehicle into a canal. Total damage in Florida was around $800 million. Irene also contributed slightly to ongoing flood problems in North Carolina in the aftermath of Hurricane Floyd.

The worst of the effects from Jose occurred in Antigua and Barbuda, as winds up to were reported. About 500 houses and a newly built church were destroyed. About 50% of residents were left without water and 90% of people experienced power outages. Overall, twelve people were injured, one fatality occurred, and an elderly blind man was listed as missing. Flooding in Saint Kitts and Nevis washed out several major roads and caused landslides. Additionally, one person was killed during the storm. In Sint Maarten, mudslides and flooding damaged houses and roads, especially those in low-lying areas. Strong winds and heavy rainfall in Puerto Rico and the United States Virgin Islands caused extensive power outages and minor damage, estimated at $40,000. Overall, losses from the storm was less than $5 million.

Tropical Storm Katrina

The remnants of a cold front moved southward through the western Caribbean Sea on October 22, leading to a broad low pressure area forming by October 26. The pulsing thunderstorms and circulation organized into Tropical Depression Fifteen on October 28, located about 175 mi (280 km) east of Bluefields, Nicaragua. Although wind shear displaced the circulation from the thunderstorms, the depression also developed rainbands, a sign of intensification. Late on October 29, the NHC upgraded the depression to Tropical Storm Katrina, based on gale-force winds recorded by the Hurricane Hunters. Soon thereafter, Katrina moved ashore eastern Nicaragua near Puerto Cabezas with peak winds of 40 mph (65 km/h) around 00:00 UTC on October 30. However, there was little remaining thunderstorms, and Katrina failed to re-intensify before making landfall again near the northern Belize–Mexico border on October 31. Katrina dissipated on November 1 off the northern coast of the Yucatán Peninsula, where it was absorbed by another cold front. The flooding also damaged five bridges in Honduras, and the cities of Tocoa and Trujillo were isolated as the Aguán and Siline rivers overflowed their banks. Katrina also destroyed water pipes that were replaced after Mitch, worth HNL 170,000 (US$9,000). Between October 30 and November 1, the remnants of Katrina produced widespread moderate rainfall across the Yucatan Peninsula, peaking at in Cunduacán. Moisture from the remnants of the storm enhanced rainfall across southern Florida in association with the cold front that absorbed the system.

Hurricane Lenny

A low pressure area developed into a tropical depression about south of the Cayman Islands at 18:00 UTC on November 13. The depression began to move in an unusual eastward track across the Caribbean Sea along the southern periphery of a trough and strengthened into Tropical Storm Lenny on the following day. It attained hurricane status south of Jamaica on November 15 and passed south of Hispaniola and Puerto Rico over the next few days. Beginning on November 16, Lenny underwent rapid deepening, becoming a major hurricane early on November 17 while south of the Mona Passage. Later that day, Lenny peaked as a Category 4 hurricane with winds of and a minimum pressure of while near Saint Croix. It gradually weakened due to wind shear while moving through the Leeward Islands, where it struck Saint Martin, Anguilla, and Saint Barthélemy. The system weakened to a tropical storm on November 19. After clearing the islands, Lenny deteriorated to a tropical depression on November 21 and dissipated on November 23, while located about east of the Lesser Antilles.

Before moving through the Lesser Antilles, Lenny produced rough surf that killed two people in northern Colombia. Despite the hurricane's passage near Saint Croix at peak intensity, In nearby Antigua and Barbuda, the hurricane killed one person; torrential rainfall there contaminated the local water supply. Significant storm damage occurred as far south as Grenada, where high surf isolated towns from the capital city.

Storm names

The following list of names was used for named storms that formed in the north Atlantic in 1999. This was the same list used for the 1993 season as no names were retired from that year. A storm was named Lenny for the first (and only) time in 1999.

{| style="width:80%;"

Arlene
Bret
Cindy
Dennis
Emily
Floyd
Gert

Harvey
Irene
Jose
Katrina
Lenny

Retirement

The World Meteorological Organization retired the names Floyd and Lenny in the spring of 2000 from the Atlantic hurricane name lists on account of their destructiveness. They were replaced with Franklin and Lee for the 2005 season.

Season effects

This is a table of all of the storms that formed in the 1999 Atlantic hurricane season. It includes their name, duration, peak classification and intensities, areas affected, damage, and death totals. Deaths in parentheses are additional and indirect (an example of an indirect death would be a traffic accident), but were still related to that storm. Damage and deaths include totals while the storm was extratropical, a wave, or a low, and all of the damage figures are in 1999 USD.

Notes

References

External links

Monthly Weather Review
National Hurricane Center 1999 Atlantic hurricane season summary