Criteria

Characteristic of the 2017 Atlantic Hurricane Season

All-Time Record

Ÿ The ACE units produced by the Atlantic basin storms in September (155.4, surpassed that of September 2004 to become the most active calendar month in the Atlantic on record.

Ÿ More ACE was generated on September 8, 2017 than any other calendar day in the Atlantic basin on record, jointly contributed by Hurricanes Jose, Irma and Katia.

Ÿ First time on record since that to Category 4 major Hurricanes (Irma and Harvey) made landfall in the continental USA in a single year.

Ÿ Ophelia was the easternmost major hurricane in the Atlantic basin on record that underwent extratropical transition as it impacted the United Kingdom and Ireland in mid-October.

Ÿ Tropical Storm Bret was the earliest named storm to form in the main development region¹² on record, surpassing the record of Tropical Storm Ana in 1979.

Ÿ Harvey was the most enduring tropical storm on record after making landfall as a hurricane in Texas staying at tropical storm strength or greater for 117 hrs.

Ÿ Harvey was the wettest tropical cyclone in the US history, dropping 34 trillion gallons of water across East Texas and Western Louisiana and almost 52 inches of rain in six days

Ÿ Harvey produced 51.8 inches of rain at Cedar Bayou, Texas—the most ever recorded in US mainland from a tropical cyclone.

Ÿ Hurricane Harvey was the first storm to make two landfalls in the Gulf of Mexico more than 60 hours apart.

Ÿ Irma was the strongest Atlantic storm in Caribbean Sea on record.

Ÿ Irma was the strongest hurricane to hit the Leeward Islands on record.

Ÿ Irma stayed as a Category 5 hurricane in the Atlantic for the longest time (78 hours)

Ÿ Irma is the only tropical storm to have sustained very intensive wind speeds at 185 mph (298 km/h) for about 37 hours.

Ÿ Hurricane Nate’s forward speed of 28 mph (45 km/hr) was the fastest recorded motion of a hurricane in the Gulf of Mexico.

Ÿ Hurricane Irma was the closest approach of a Category 5 hurricane to the Turks and Caicos Islands

Compared to Other Seasons

Ÿ The most active since the record-breaking season of 2005, with 17 named storms, 10 hurricanes, and six major hurricanes above Category 3.

Ÿ Seventeen named storms formed, above the 1950-2016 average1 (11.6 named storms) and above the 1996-2016 average (14.4).

Ÿ Ten hurricanes formed, above both the 1950-2016 average (6.2 hurricanes) and 1996-2016 average (7.2).

Ÿ There were six major hurricanes (Category 3 or greater), which lies above the average of 1950-2016 (2.5 major hurricanes and 1996-2016 (3.3).

Ÿ The seventh season since 1950 to have at least six major hurricanes.

Ÿ Hurricanes developed in the Atlantic for more than 52 days, being the sixth highest number of days since 1851, the most since 2004, and are more than double the seasonal average.

Ÿ The stretch of hurricanes was the longest since the early twentieth century.

Ÿ The ACE index total of 226 was well above both the 1950-2016 (101 ACE) and 1996-2016 (124 ACE) averages.

Ÿ The season’s ACE total ranks as the fourth largest since 1950 and the largest since 2005.

Ÿ Hurricane Irma (the season’s largest ACE contributor), generated 67.5 ACE units, the second largest ACE total for a single storm in the Atlantic since 1966 when the satellite era began.

Ÿ The TIKE total was approximately 25% higher than the annual mean calculated from 1990 onward.

Ÿ Tropical Storm Arlene was the second tropical storm on record to form in the month of April (20th), before the official start of the hurricane season since Ana in 2003.

Ÿ Tropical Storm Bret was the lowest latitude named storm in the month of June, since 1933.

Ÿ The joined presence, on June 20, of Tropical Storms Cindy and Bret in the Atlantic, marked the first time in 49 years, and only the third time on record, that two named storms co-existed in the Atlantic before July 1.

Ÿ Hurricane Harvey was the first Category 4 hurricane to make landfall in the US since Hurricane Charley in 2004.

Ÿ Hurricane Irma was the first Category 5 hurricane to make landfall on the Camaguey Archipelago of Cuba since 1924.

Ÿ It was the first time since 2010 that three hurricanes (Irma, Jose, and Katia) were active in the Atlantic basin at the same time (September 8)

Ÿ Hurricane Nate was the first hurricane to make landfall in Louisiana since Hurricane Katrina in 2005 and the fourth hurricane to make landfall in mainland USA in 45 days.

Ÿ The fourth on record and the first year since 1893 to have 10 consecutive storms gain hurricane status in the Atlantic basin.

Ÿ Hurricane Irma was the first Category 5 hurricane to make landfall in the Bahamas since Andrew in 1992.