Atlantic hurricane season 2017: Facts and figures thus far
Monday, September 18, 2017, 6:25 PM - As we move into the second half of the Atlantic hurricane season, which typically reaches its peak in activity around Sept. 10, it’s a good time to look back at the season so we can gauge where we currently stand in terms of the long term averages and records.
Though this is not the most active hurricane season ever recorded, it comes at the end of a long, quiet period in Atlantic hurricane activity, and has produced two back to back major hurricane landfalls along the U.S. coast with devastating effects.
Dr. Phil Klotzbach, Research Scientist at the Department of Atmospheric Science at Colorado State University, is an expert in both hurricane seasonal forecasting and hurricane climatology. He frequently shares summaries of facts and statistics about the current hurricane season through his Twitter account (@philklotzbach).
Here are just a few of Dr. Klotzbach’s notes about the 2017 season so far:
- Through Sept. 11, Atlantic Accumulated Cyclone Energy (a measure of overall tropical activity in the Atlantic basin) is the seventh highest year to date. Years with higher values of ACE to date are 1893, 1933, 1950, 1995, 2004, and 2005.
- Through Sept. 10, the Atlantic hurricane season has produced 12.75 major hurricane days (thanks to Harvey, Irma, and Jose). The only years with more major hurricane days to date were 1899 and 1933.
- The continental U.S. had two Category 4 landfalls (Harvey and Irma) in the same year for the first time on record. But in 1933 two Category 3 hurricanes made landfall within 23 hours of each other – one in Brownsville, TX and one in Jupiter, FL.
- Hurricane Harvey broke the longest-running U.S. landfalling major hurricane drought at 4323 days. Hurricane Irma made landfall only 16 days later.
- Hurricane Harvey produced 1.31 m (51.88 inches) of rain at Cedar Bayou, Texas – the most ever recorded in the mainland U.S. from a tropical cyclone, and breaking the old record of 1.22 m (48 inches) set in Texas by Tropical Storm Claudette in 1979. (It was still raining when the gauge broke, so the number may be higher than even Hawaii’s record of 1.32 m [52 inches])
- Hurricane Irma reached a maximum wind speed of 298 km/h (185 mph) – tied with the Florida Keys Hurricane of 1935, Gilbert (1988), and Wilma (2005) for the second strongest max winds of all time in an Atlantic hurricane. The record is held by Hurricane Allen (1980), which reached 305 km/h (190 mph).
- Hurricane Irma maintained 298 km/h (185 mph) for 37 hours, the previous record time anywhere on the globe for a storm of that intensity was Typhoon Haiyan, which was at peak intensity for 24 hours.
- Hurricane Irma was a Category 5 for 3.25 days, tied with the Cuba Hurricane of 1932 as the longest time at Category 5 strength.
- Hurricane Irma generated more Accumulated Cyclone Energy than any Atlantic tropical cyclone on record, and more than the first eight named storms of the season (including Harvey) combined.
- Hurricane Irma was the first Category 5 hurricane to make landfall in Cuba since 1924, and the first major hurricane (Category 3 or greater) to make landfall in Florida since Wilma (2005)
- Hurricane Irma’s second US landfall on Marco Island, Fla., was at the exact same latitude and longitude, as well as the same Saffir-Simpson Category as Wilma in 2005 (25.9°N, 81.7°W).
As of mid-September, we are only through the first half of the 2017 Atlantic hurricane season. Though we don’t expect the second half to be quite as active at the last few weeks, many of the same favorable conditions for storm formation and intensification will continue to be present through the early fall. So it is very likely that we will hear from the tropics at least a few more times before the season ends.
Note: Since this list was complied, Hurricane Maria, a Category 4 storm, developed in the Atlantic.
Watch below: Prior to a hurricane arriving, follow these steps
Source: Dr. Phil Klotzbach