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On the morning of Aug. 30, over the open waters of the far eastern Atlantic, Irma became the ninth named tropical system of the 2017 Atlantic hurricane season. By the next day, it had rapidly intensified into a major hurricane and was being closely scrutinized by meteorologists.

Meteorologists provided early warnings of US impacts

Even with the storm thousands of miles away from the Caribbean and mainland United States, AccuWeather meteorologists and other agencies knew that the storm would have the potential to be a serious threat to life and property.

This is due to our team of over 100 operational meteorologists, including tropical experts with decades of experience analyzing weather patterns, weather forecast computer model data, and other proprietary inputs, according to AccuWeather Vice President of Forecasting and Graphic Operations Marshall Moss.

Fresh off the catastrophic impacts of Hurricane Harvey in South Texas, it had become clear that another strike on the U.S. by a major hurricane was a growing possibility.

"The heightened awareness from the disastrous impact of Harvey, I think, helped elevate the level of awareness and need to prepare for Irma," said Jonathan Porter, vice president of business services for AccuWeather Enterprise Solutions, the AccuWeather specialized team responsible for providing highly detailed and actionable weather warnings and forecasts for businesses around the world.


With Harvey’s devastation fresh on the mind of the American people, advance notice and information on Irma’s possible impacts in the U.S. were vital.

“For about a week [ahead of time], we were talking about Florida impacts,” Moss said.

Irma, a record-shattering storm, sustained 185-mph winds for 37 hours, the longest any hurricane or typhoon in the world has maintained such intensity.

Irma wrought tremendous devastation across the northern Caribbean en route to Florida. Irma's first Florida landfall occurred Sunday, Sept. 10 as a Category 4 storm. The second came later in the day at Marco Island, Florida, located near Naples.

Florida Gov. Rick Scott declared a state of emergency on Monday, Sept. 4, and the first mandatory evacuations in the Florida Keys began on Sept. 6.

Floridians, who hadn’t seen a major hurricane (Category 3 or higher) pound their state since Wilma in 2005, seemed to grasp the urgency of the situation. Over 6 million residents left in one of the largest evacuations in U.S. history in the days prior to landfall.


The evacuation proved vital because Irma’s devastating impacts were felt statewide.

Although the storm came up the west coast, 100-mph winds reached the east coast. Storm surge and record-setting flooding besieged cities as far north as Jacksonville.

“It’s a good thing that people were brought out of the way," Moss said, adding that the forecast accuracy and lead time allowed enough time for millions to evacuate.

As of Sept. 14, at least 32 people have died in Florida, South Carolina and Georgia while another 38 people were killed in the Caribbean, according to the Associated Press.

Over 15 million people were left without power across Florida, one of the largest power outages to ever occur from a natural disaster.

Major hurricanes killed thousands in years past

While the death toll may rise in the U.S. and Caribbean as recovery efforts continue, the number of casualties for a storm of Irma’s magnitude could have been much higher.

Key advancements in forecasting as well as disaster preparation and response at the local and federal levels of government helped prevent a death toll that could’ve skyrocketed into the hundreds or thousands as in past years.

In 1900, a massive hurricane struck Galveston, Texas, and unleashed a storm surge of 8-15 feet. Around 8,000 people were killed although some estimates surpass 12,000. In 1928, more than 1,800 people died in Florida due to the San Felipe-Okeechobee hurricane.

Hurricane Donna killed over 50 people when it took a similar track to Irma in 1960 as it slammed the Florida Keys as a Category 4 before curving northeastward across the Florida Peninsula. Andrew was the last Category 5 storm to strike the U.S. when it slammed South Florida in 1992; the storm was responsible for 23 deaths.

For this century, the deadliest storm to lash the U.S. is Katrina in 2005, which killed approximately 1,200 people in Louisiana and Mississippi. More recently, Superstorm Sandy claimed at least 147 lives in the Northeast during October 2012.

AccuWeather Expert Senior Meteorologist and Chief Operating Officer Evan Myers said that accurate forecasts help engender trust with the public.

“Accuracy breeds confidence,” Myers said. “The public has much more confidence in the forecast than 20-30 years ago because the forecasts are more accurate. So when a forecast is issued, people are more likely to believe it, and so they’re more likely to react to it and get out of harm’s way.”

AccuWeather predicts that Irma will cost at least $100 billion in damage. Along with the predicted $190 billion in damage from Hurricane Harvey, the two storms could cost nearly $300 billion with two months left in the Atlantic season.

Communication, forecasting have improved significantly in past decade

A key to improved forecasting capability according to AccuWeather Hurricane Expert Dan Kottlowski is the way satellite technology is utilized. Along with tools used to collect key atmospheric measurements such as flying an aircraft around the outer periphery of hurricanes, this helps send better data to the computer models, he explained.

We didn't have the robust set of data and input into the computer models back during Katrina, he said.

Kottlowski credited the government, particularly the National Oceanic and Atmospheric Administration (NOAA), for better public interaction to help promote awareness of a hurricane’s dangers. Each year in May, NOAA conducts a hurricane preparedness week.

As one of the first NOAA Weather-Ready Nation Ambassadors, AccuWeather's year-round prepardness program, AccuWeather Ready, focuses on keeping people informed and safe. The AccuWeather Ready page features preparedness checklists, videos and news content to help people stay safe when tropical storms and hurricanes threaten.

Kottlowski said a monster storm like Irma is the reason people should develop a hurricane safety plan in the months ahead of the Atlantic hurricane season, which begins in June.

Chris Renschler, an associated professor of geography at the University of Buffalo and extreme events researcher, said in the past there were limited model predictions and not as much information available to the public.

Today, more weather data is available for public consumption and this information is readily translated and transported to the people, said Renschler, who was part of New York state’s respond commission after Sandy.


Even though emergency managers can issue mandatory evacuations, people can decide to evacuate on their own based on the available information, according to Renschler.

"I think that has changed quite a bit over the past 10 years," he said.

Social media has helped the dissemination of information which allows people to continuously track news updates from the palm of their hands, Renschler added.

“I have little doubt that social media helped reduce the number of fatalities when the forecasts and warnings were spread ahead of the storm," AccuWeather Social Media Manager Jesse Ferrell said.

For meteorologists, while it’s their job to warn the public that devastating impacts will occur with a storm like Irma, it can take an emotional toll.

“It’s heart-wrenching to forecast, but we know we need to get that word out to help save lives and protect property. I think the weather enterprise as a whole did a great job with that overall,” Moss said.