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Irma's Notable Extremes: All the Historical Benchmarks It Has Hit So Far
Published: September 9, 2017
Hurricane Irma is one of the most powerful hurricanes to roam the Atlantic Basin in more than a decade, and it could hit more historical benchmarks in the days ahead.
(HURRICANE CENTRAL: Latest Coverage on Irma)
Here's a rundown of Irma's notable extremes so far.
Strongest Winds in Almost 12 Years
Irma's maximum sustained winds have so far maxed out at 185 mph. Those winds are well above the 157 mph Category 5 threshold and are the highest registered in any Atlantic hurricane since 2005.
Hurricane Wilma on Oct. 19, 2005, was the last hurricane to have maximum sustained winds reach 185 mph.
One of Four Hurricanes With 185+ MPH Winds
The 185 mph winds also place Irma in the upper echelon of Atlantic hurricanes based on wind speed.
Only three other hurricanes have had winds of 185 winds or greater, including Wilma (2005), Gilbert (1988) and Allen (1980), according to Dr. Phil Klotzbach, a tropical scientist at Colorado State University.
Allen had the strongest winds of those four hurricanes, maxing out at 190 mph in early August 1980.
Longest Duration of 185 Winds Anywhere in the World
Irma's winds were at 185 mph for 37 hours. That's the longest a tropical cyclone has maintained winds at that level or stronger anywhere in the world, according to Klotzbach.
The previous record was Super Typhoon Haiyan (2013) in the northwest Pacific which held winds of that intensity for 24 hours.
Most Powerful Hurricane to Strike the Leeward Islands
Irma's maximum winds were 185 mph as it raked through the Leeward Islands, including Barbuda, Anguilla and Saint Martin.
Klotzbach says that Irma's winds are the strongest for any hurricane on record to wallop the Leeward Islands region, beating out the Okeechobee Hurricane (1928) and David (1979). Both of those hurricanes had 160 mph winds at their peak in the Leeward Islands.
(NOAA GOES-16 Experimental)
Lowest Central Pressure in a Decade
The central pressure observed in Irma dropped to 914 millibars early Wednesday morning, the lowest pressure for any Atlantic hurricane since Dean in August 2007, according to Klotzbach.
Irma's pressure ranks as the tenth-lowest in the satellite era (since 1966) for the Atlantic.
In general, a lower pressure means a more intense hurricane in terms of its winds and overall destructive potential. Conversely, a higher pressure indicates a weaker system when it comes to wind speeds.
Irma Ranks Among Longest-Lived Category 5 Hurricanes
Hurricane Irma was a Category 5 for 3.25 days total, tying it with the Cuba Hurricane (1932) for the longest lifetime as a Category 5.
In the satellite era, since 1966, Irma was the longest-lived Category 5 hurricane, according to Klotzbach.
Hurricane Allen (1980) and Hurricane Ivan (2004) held the previous record for the longest duration as a Category 5 in the Atlantic at three days total.
2017 Could Be the First Year With Two U.S. Category 4 Landfalls
Irma has a chance to be the second Category 4 hurricane landfall in the U.S. this season.
The first Category 4 landfall was Hurricane Harvey which roared ashore near Rockport, Texas, with 130 mph winds on Aug. 25.
In historical records dating to 1851, the U.S. has never been struck by two Category 4 or stronger hurricanes in the same year, according to Bob Henson, a meteorologist with wunderground.com.
First Category 5 Hurricane to Make Landfall in Cuba Since 1924
Irma made landfall as a Category 5 hurricane late Friday night along the Camaguey Archipelago of Cuba.
This was the first Category 5 landfall in Cuba since the Cuba Hurricane of 1924, according to Klotzbach.
Irma also made landfall as a Category 5 in the Bahamas, the first such occurrence since Hurricane Andrew (1992).
In the Turks and Caicos, Irma made the closest approach to the archipelago of any Category 5 hurricane on record.
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