The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in recorded history, shattering previous records on repeated occasions. The impact of the season was widespread and ruinous with at least 2,280 deaths and record damages of over $100 billion USD. Of the storms that made landfall, the five of the seven major hurricanes that did so—Dennis, Emily, Katrina, Rita, and Wilma—were responsible for most of the destruction. The Mexican states of Quintana Roo and Yucatán and the U.S. states of Florida and Louisiana were each struck twice by major hurricanes; Cuba, The Bahamas, Haiti, Mississippi, Texas, and Tamaulipas were each struck once and in each case brushed by at least one more. The most catastrophic effects of the season were felt on the United States' Gulf Coast, where a 30-foot (10 meter) storm surge from Hurricane Katrina caused devastating flooding that inundated New Orleans, Louisiana and destroyed most structures on the Mississippi coastline, and in Guatemala, where Hurricane Stan combined with an extratropical system to cause deadly mudslides.
The season officially began on June 12005, and lasted until November 30, although effectively the season persisted into January 2006 due to continued storm activity. A record twenty-eight tropical and subtropical storms formed, of which a record fifteen became hurricanes. Of these, seven strengthened into major hurricanes, a record-tying five became Category 4 hurricanes and a record four reached Category 5 strength, the highest categorization for hurricanes on the Saffir-Simpson Hurricane Scale. Among these Category 5 storms were Hurricanes Katrina and Wilma, the former the costliest and the latter the most intense Atlantic hurricane on record.
Forecasts of hurricane activity are issued before each hurricane season by noted hurricane expert Dr. William M. Gray and his associates at Colorado State University (CSU), and separately by forecasters with the U.S. Government's National Oceanic and Atmospheric Administration (NOAA). Prior to and during the 2005 season, Dr. Gray issued four forecasts, each time increasing the predicted level of activity. The NOAA issued two forecasts, one shortly before the season and one two months into the season, drastically increasing the predicted level of activity in the second release. Nonetheless, all forecasts fell far short of the actual activity of the season.
Preseason forecasts
On December 3, 2004, Dr. Gray's team issued its first extended-range forecast for the 2005 season, predicting a slightly above-average season. Additionally, the team predicted a greatly increased chance of a major hurricane striking the East Coast of the United States and the Florida peninsula. Though the forecast predicted above-average activity, the level predicted was significantly less than the 2004 season. On April 1, 2005, after confirming that El Niño conditions would not develop, Dr. Gray and his team revised the December forecast upward, expecting thirteen tropical storms instead of eleven and seven hurricanes instead of six. In addition, the chance of a storm impacting the United States was raised slightly.
On June 9, nearly two months earlier than when the 2004 season started, Tropical Storm Arlene formed in the western Caribbean, crossing Cuba before making landfall on the Florida Panhandle on the 11th. Arlene caused only moderate damage, although one swimmer was caught in a riptide and drowned in Miami Beach, Florida.Tropical Storm Bret formed in the Bay of Campeche on June 28 and made landfall in Veracruz the next morning. The storm damaged hundreds of homes and caused flooding which killed two people.Hurricane Cindy formed in the Gulf of Mexico on July 4. Originally thought to be a tropical storm, Cindy made landfall in Louisiana on the 5th as a minimal hurricane, dropping up to 5 inches (130 mm) of rain, spawning several tornadoes, and killing three people. Cindy was upgraded to a hurricane in the post-storm analysis.On July 5, Hurricane Dennis formed in the eastern Caribbean; it crossed Grenada before intensifying into a Category 4 hurricane, the strongest ever recorded in July with a pressure of 930 mbar (hPa). Dennis struck Cuba at full force, then made a final landfall on the Florida Panhandle. The hurricane killed 89 people (mostly in Haiti) and caused $4â€"$6 billion in damages in Cuba and the United States.Soon thereafter, Hurricane Emily formed in the Atlantic on July 11. It entered the Caribbean Sea and quickly intensified to a Category 4 storm, breaking Dennis's record for July intensity when its pressure reached 929 mbar (hPa). Emily then briefly reached Category 5 intensityâ€"the earliest such storm ever recorded in the Atlantic. Emily crossed the Yucatán Peninsula at Category 4 strength before hitting Tamaulipas at Category 3 strength. Emily killed at least 14 people over the course of its path. An estimated $400 million in damages have been reported.Tropical Storm Franklin formed off the Bahamas on July 18. The storm moved northeast and became extratropical off the coast of Atlantic Canada without ever having threatened land.Tropical Storm Gert followed soon after on July 24. Gert struck Veracruz near where Emily had hit a few days before; roughly 1,000 people were evacuated for fear of flooding, but no damages or deaths were reported.Like July, August also got off to a fast start: Tropical Storm Harvey formed southwest of Bermuda on August 3. Harvey dropped some rain on Bermuda as it moved to the northeast; it became extratropical on August 8 in the open Atlantic Ocean.The tropical depression that would become Hurricane Irene formed west of the Cape Verde Islands on August 4. The system moved west and north and did not reach hurricane strength until August 14, at which point it became the second Cape Verde-type hurricane of the season. Irene turned northeast and briefly reached Category 2 status before weakening and becoming extratropical on August 18. It never posed a threat to land.Tropical Depression Ten formed east of the Lesser Antilles on August 13. The system dissipated the next day. Its remnants soon merged with another system and eventually contributed to the formation of Hurricane Katrina.Tropical Storm Jose followed, forming in the Bay of Campeche on August 22. It strengthened rapidly but quickly reached the coast and made landfall in the Mexican state of Veracruz on August 23, preventing further strengthening. Jose forced 25,000 people to evacuate their homes in Veracruz and killed six people in the state of Oaxaca; two more were reported missing.
Hurricane Katrina formed in mid-August over the Bahamas. It became a tropical storm on August 24 and reached hurricane intensity before making landfall in south Florida as a minimal hurricane. A few hours later, the storm entered the Gulf of Mexico and intensified rapidly into a Category 5 hurricane while crossing the Loop Current on August 28. Katrina made landfall on August 29 near the mouth of the Mississippi River as an extremely large Category 3 hurricane. Storm surge caused catastrophic damage along the coastlines of Louisiana, Mississippi, and Alabama. Levees separating Lake Pontchartrain from New Orleans, Louisiana were breached by the surge, ultimately flooding about 80% of the city. Wind damage was reported well inland, impeding relief efforts. Katrina is estimated to be responsible for at least $81.2 billion in damages, making it the costliest recorded hurricane in U.S. history. It was the deadliest U.S. hurricane since the 1928 Okeechobee Hurricane, killing at least 1,836 people.Tropical Storm Lee formed out in the Atlantic on August 31 but dissipated several days later without having threatened land.Hurricane Maria led off the month of September, forming as a tropical storm well east of the Leeward Islands on September 2. Maria reached its peak as a Category 3 hurricane on September 5, turning northeast and weakening before becoming extratropical on the 10th. Unusually, this extratropical storm strengthened as it moved toward Iceland; its remnants struck Norway where one person was killed in a landslide.Hurricane Nate formed southwest of Bermuda on September 5 and moved northeast as it strengthened into a strong Category 1 hurricane. Nate became extratropical on the 10th; the storm never approached land, although it did interfere with Canadian naval vessels en route to the Gulf Coast to help in Katrina relief efforts.Hurricane Ophelia formed as a tropical depression in the Bahamas on September 6 and almost immediately made landfall on Grand Bahama. It became a tropical storm off the coast of Florida before strengthening into a large Category 1 storm and raking a long stretch of the southern North Carolina coast with heavy winds and storm surge on the 12th and 13th. The hurricane's eye never made landfall and moved back out to sea before becoming extratropical on the 17th and striking Atlantic Canada. Damages were around $70 million.Hurricane Philippe formed east of the Leeward Islands on September 17. It moved northwards, reaching Category 1 intensity before weakening and finally dissipating on the 23rd. No landmasses were affected.Hurricane Rita formed as a tropical storm over the Turks and Caicos Islands on September 18. The storm reached Category 2 intensity as it moved south of the Florida Keys on September 20. Rapid intensification ensued as Rita moved into the Gulf of Mexico, and Rita became a Category 5 hurricane on the 21st, becoming the third (now fourth) most intense hurricane ever recorded in the Atlantic Basin. Rita made landfall near the Texas-Louisiana border on September 24. Major flooding was reported in Port Arthur and Beaumont, Texas, while Cameron and Calcasieu Parishes in Louisiana were devastated. Offshore oil platforms throughout Rita's path also suffered significant damage. Six people are confirmed dead from Rita's direct effects, and total damage from the storm is estimated at about $10 billion. One hundred and thirteen indirect deaths have been reported, mostly from the mass exodus from Houston, Texas and surrounding counties.Tropical Depression Nineteen formed west of the Cape Verde Islands on September 30 but dissipated on October 2 without having threatened land.Hurricane Stan was the first October storm, reaching tropical storm status on October 2 just before crossing the Yucatán Peninsula. In the Bay of Campeche, Stan briefly reached hurricane strength before making landfall south of Veracruz, Veracruz, on October 4. Stan was a part of a large system of rainstorms, which dropped torrential rainfall that caused catastrophic flooding and mudslides over southern Mexico and Central America. Well over 1,000 total deaths were caused by the flooding, of which 80â€"100 are directly attributed to Stan. An initially unnoticed Unnamed Subtropical Storm was discovered by the NHC during the postseason analysis. This short-lived subtropical storm formed on October 4 south of the Azores and was absorbed by an extratropical low the next day, after passing over those islands.
The Mexican state of Quintana Roo was also heavily hit, suffering billions of dollars in damages when Hurricanes Emily and Wilma both made landfall between Cozumel and Cancún. Wilma was particularly devastating, lashing the area with major hurricane-force winds for over a full day, and was possibly the most damaging hurricane in Mexican history.
Wilma caused widespread heavy damage in south Florida, causing $16.8 billion in damages total in the United States.Tropical Storm Delta, Hurricane Epsilon and Tropical Storm Zeta all formed over the cold waters of the late-season eastern Atlantic, much like Hurricane Vince (though at lower latitudes). All three persisted in the face of heavy wind shear, and Epsilon managed to reach hurricane strength over waters well below the temperatures previously thought necessary for hurricane formation. Epsilon became the longest-lasting December hurricane while Zeta became the longest-lasting storm in January.
During the season 28 storms formed (27 named and one unnamed), surpassing almost all records for storm formation in the Atlantic. More tropical storms, hurricanes, and Category 5 hurricanes formed during the season than in any previously recorded Atlantic season; the only major record for number of storms the season did not capture was most major hurricanes, still held by the 1950 season.
The season was the first season to use "V" and "W" names, and when the season ran out of official alphabetical names after the use of Wilma, forecasters resorted to using letters from the Greek alphabet for the first time (although Alpha and Delta had been used for subtropical storms in the 1970s).
Almost every storm in 2005 has set a record for early formation. Of the twenty-eight storms which formed, twenty-two of them qualified as the earliest-forming storm of that number; starting with Hurricane Dennis, almost every storm was such.
Three of the six most intense hurricanes on record formed in 2005, topped off by Hurricane Wilma's 882 mbar minimum pressure, shattering the 17-year-old record set by Hurricane Gilbert. Hurricanes Emily, Katrina and Rita also attained Category 5 intensity, and Hurricanes Rita and Katrina became the fourth and sixth most intense recorded Atlantic storms, respectively. Hurricane Emily was not originally recorded as a Category 5 storm, but it was upgraded in the post-storm analysis by the National Hurricane Center. The 2005 season is the only season on record with four Category 5 storms on the Saffir-Simpson Hurricane Scale; the previous record was only two. In addition, Hurricane Dennis reached Category 4 status, tying the record set by the with five Category 4 storms.
Early strength and activity
In July, Hurricane Dennis became the strongest storm to form prior to August and the earliest Category 4 storm to form in the Caribbean. When Hurricane Emily reached Category 5 intensity later in the month, the 2005 season became the only season to have two hurricanes reach Category 4 intensity before the end of July; Emily also broke Dennis's nine-day-old record for the strongest storm on record before August. Emily was also the first Category 5 hurricane ever recorded in July and the earliest by nearly three weeks (beating Hurricane Allen). The high level of activity and strength was reflected in the accumulated cyclone energy value at the end of July; at 63 it was the highest ever.
Additionally, seven storms formed before the end of July, breaking the record of five set in the 1887, 1933, 1936, 1959, 1966, and 1995 seasons. Five of those storms formed during July, also a new record.
Late activity
After forming on November 29, Hurricane Epsilon became the longest-lasting December hurricane on record when it maintained hurricane strength from December 2 to December 7. Epsilon is the third-strongest hurricane ever recorded in the month of December; only Hurricane Nicole of 1998 and an unnamed storm in the 1925 season were stronger.
When Tropical Storm Zeta formed on December 30, it came second only to Hurricane Alice (also December 30, 1954, but later in the day) as the latest ever that the last storm of the season formed. Zeta also became only the second storm, after Alice, to persist through the end of year and still be active at the start of the next. In addition, Zeta was the longest-lived tropical cyclone to form in December and cross over into the next year, and it was also the longest-lived January tropical cyclone.
The following names were used for tropical storms and hurricanes that formed in the North Atlantic in 2005. This was the same list used for the 1999 season, with the exceptions of Franklin and Lee, which replaced Floyd and Lenny. The names not retired from this list will be used again in the 2011 Atlantic hurricane season. Storms were named Franklin, Lee, Maria, Nate, Ophelia, Philippe, Rita, Stan, Tammy, Vince, Wilma, Beta, Gamma, Epsilon, and Zeta for the first time in 2005 (the names Alpha and Delta had been previously used in 1972 for two subtropical storms, but this is the first time they have been used in this way). This season used fifteen previously unused names, the most ever in an Atlantic season. Additionally, a subtropical storm that formed in early October was not recognized as such at the time and so did not receive a name.
Vince and Wilma were the first named "V" and "W" storms ever in the Atlantic basin. The naming of Wilma exhausted the 2005 list, the first time in Atlantic naming history that all names in the list have been used. Beginning with Alpha, the 2005 season was the first time in Atlantic hurricane history that Greek letters were used due to the exhaustion of the primary list.
