Matthew Is the Most Powerful Atlantic Hurricane in a Generation. Here’s What You Need to Know.

October 5, 2016 | 6:09 am
NASA
Astrid Caldas
Senior Climate Scientist

UPDATE (October 7, 10:40 a.m.): According to NOAA’s 10/7/16 8 a.m. EDT update, Hurricane Matthew currently has maximum sustained winds near 120 mph, and has been downgraded to a Category 3. Storm surge continues to be the main concern, with the deepest water occurring along the immediate coast in areas of onshore winds. There is still danger of life-threatening inundation along the Florida east coast, the Georgia coast, and the South Carolina coast. Learn more.

UPDATE (October 6, 7:55 p.m.): To help you evaluate the implications of Matthew’s coming storm surge, my colleague and fellow climate scientist Brenda Ekwurzel has just published the post, Hurricane Matthew Storm Surge: How to Evaluate Its Potential Magnitude and Impacts.

UPDATE (October 6, 2:50 p.m.): According to the latest update from NOAA, Hurricane Matthew currently has maximum sustained winds near 140 mph, and has been upgraded to a Category 4 storm. While further strengthening is possible, it is expected to remain a Category 4 hurricane as it approaches the Florida coast.

One of the most serious issues with this hurricane is storm surge, which has caused terrible floods in Cuba, and even worse ones in the Bahamas. NOAA has restated the danger of life-threatening inundation during the next 36 hours along the coast from Deerfield Beach, Florida to Edisto Beach, South Carolina; and during the next 48 hours from north of Edisto Beach to South Santee River, South Carolina. Learn more.

UPDATE (October 5, 5:20 p.m.): The latest update from NOAA has new predictions for rainfall and storm surge and warns of the danger and possibility of life-threatening inundation during the next 36 hours along the Florida east coast from Deerfield Beach to the Flagler/Volusia county line, and during the next 48 hours from north of the Flagler/Volusia county line to the Savannah River. Learn more.

 

It is hard to pull one’s eyes away from the images of Haiti in the aftermath of Hurricane Matthew. If one needed proof that we live in an indifferent universe, that broken land and its suffering people caught in a new, unfolding catastrophe should suffice.

But even as we watch disaster grip Haiti, reports are beginning to flow of a potential U.S. East Coast landfall and mandatory evacuations. Our coastal communities, while so well-resourced and resilient in comparison to Haiti, are still woefully unprepared for major storms. They now need to mobilize for Hurricane Matthew.

Hurricanes are getting increasingly destructive

Through the fog of presidential politics that has enveloped the media, news of this storm is beginning to reach people and disrupt lives and plans. I for one was at the airport, ready to board a flight to Florida to participate in a climate conference, when I received the news that the conference was likely going to be canceled, and that I should not travel. This is how fast this storm developed.

Matthew turned from a tropical storm into a Category 5 hurricane in just 36 hours, mainly fueled by warmer than average waters. According to Climate Signals, as of October 3, Matthew was the longest-lived Category 4-5 hurricane and had generated the most Accumulated Cyclone Energy (or ACE, a measurement that expresses the activity and destructive potential of individual tropical cyclones and entire tropical cyclone seasons) in the eastern Caribbean of any Atlantic hurricane on record.

More powerful hurricanes are not a surprise, given global warming and other factors, and recent research in this area suggests that hurricanes in the North Atlantic region have been intensifying over the past 40 years (learn more in this comprehensive review of hurricane trends and what influences them).

Percent of Atlantic hurricanes each year from 1970 to 2012 that reached categories 3, 4, and 5. Annual data (light blue) and 5-year running average (dark blue). Graphic: Union of Concerned Scientists

Percent of Atlantic hurricanes each year from 1970 to 2012 that reached categories 3, 4, and 5. Annual data (light blue) and 5-year running average (dark blue). Graphic: Union of Concerned Scientists

Impacts of disasters fall disproportionately on the world’s poor and vulnerable communities

This is particularly true of disasters with climate connections.

Matthew may end up dumping as much as 40 inches of rain in Haiti and the Dominican Republic, whipping the country with sustained winds of 145 mph (the average annual rainfall in Port-au-Prince is 33.68 inches). Already reports are coming in of the devastation it is bringing to those nations.

Cuba is also in high alert, and a 10 to 15-foot storm surge is expected in the Bahamas, where the average elevation appears to be less than 15 feet.

The impacts from Matthew will be felt by wealthy and poor communities alike, but the latter usually are not well prepared and lack the resources to rebound and get back on their feet in a timely or comprehensive manner. And this is not true only of foreign nations: many communities along the US coast find themselves in the same situation.

Florida has a whole generation of people who have not witnessed a major hurricane

Such a powerful hurricane brings rain and storm surge that can be life-threatening, as we have already seen in Haiti. With each recent update, the track of the now Category 4 hurricane has moved farther west, and closer to the US East Coast.

Right now, Matthew is on track to skim very close to the Florida coast from late Thursday, October 6 through Friday, October 7. By Saturday, October 8, the storm will begin impacting Georgia and the Carolinas. In the Southeast, some evacuation orders have already been issued.

This is a gravely serious storm, the likes of which states like Florida have not seen in a generation.  Indeed, since Hurricane Andrew, in 1992, millions of people have taken up residence along the Florida coast.

Most of today’s East Coast residents have never experienced a hurricane of this magnitude and power, nor much considered the risks. And they now have a matter of hours to prepare.

Here I will focus on what we need to know to weather this storm.  In subsequent posts, we will address what can be learned in its aftermath.

Tracking Hurricane Matthew, The National Hurricane Center's forecast track, October 6, 2 p.m. ET

Tracking Hurricane Matthew, The National Hurricane Center’s forecast track, October 6, 2 p.m. ET

Preparedness is essential and must be taken seriously

A storm moving along the Atlantic can have a variety of impacts. Such a powerful hurricane brings rain and storm surge that can be life-threatening. For Matthew, the most up-to-date predictions are:

  • Storm surge will build as the hurricane approaches land and drives water ashore. Forecasts are still preliminary given the uncertainty of the precise storm track, but suggest that coastal areas in Florida, Georgia, and the Carolinas will see flooding greater than 1 foot and greater than 3 feet in some places. Check here for the latest updates and forecasts.
  • There is currently up to a 30 percent probability of 74 mph or higher surface winds in Florida, and winds of 50-60 mph with gusts up to 70-85 mph in North Carolina, with storm surge potentially as high as 4 feet.

For those beginning to wonder what this storm may mean for them, UCS has compiled a set of resources not only for the US but for the other affected nations:

In the US, September was National Preparedness Month and the administration took that opportunity to release four new actions to increase our nation’s resilience (Leveraging Data, National Security, Building Community Capacity, and Smart Cities Initiative).

Matthew reminds us, however, that we need to continue to talk about climate, and not only our country’s disaster policy shortcomings but also (and importantly) the impacts of on the world’s poor and vulnerable communities.

UPDATE (October 7, 10:40 a.m.): According to NOAA’s 10/7/16 8AM EDT update, Hurricane Matthew currently has maximum sustained winds near 120 mph, and has been downgraded to a Category 3. It is expected to remain a Category 3 hurricane as it moves up the Florida coast, with some weakening forecast. The center of the storm will be near or over the coast of Florida most of today, and near or over the coast of Georgia and South Carolina on Saturday.

Hurricane and/or tropical storm conditions are expected to continue in Florida during the next several hours, and in Georgia and South Carolina Friday night into Saturday. Residents should look for local information and warnings.

Storm surge continues to be the main concern, with the deepest water occurring along the immediate coast in areas of onshore winds. If peak surge occurs during high tide the water could reach the following heights above ground:

  • Sebastian Inlet, Florida, to Edisto Beach, South Carolina, including portions of the St. Johns River: 7 to 11 feet
  • Edisto Beach to South Santee River, South Carolina: 4 to 6 feet
  • Jupiter Inlet to Sebastian Inlet, Florida: 4 to 6 feet
  • South Santee River, South Carolina, to Cape Fear, North Carolina: 2 to 4 feet

There is still danger of life-threatening inundation during the next 36 hours along the Florida east coast, the Georgia coast, and the South Carolina coast from Jupiter Inlet, Florida, to South Santee River, South Carolina, and during the next 48 hours from north of South Santee River, South Carolina, to Cape Fear, North Carolina.

UPDATE (October 6, 2:50 p.m.): According to the latest update from NOAA, Hurricane Matthew currently has maximum sustained winds near 140 mph, and has been upgraded to a Category 4 storm. While further strengthening is possible, it is expected to remain a Category 4 hurricane while it approaches the Florida coast.

One of the most serious issues with this hurricane is storm surge, which has caused terrible floods in Cuba, and even worse ones in the Bahamas. NOAA has restated the danger of life-threatening inundation during the next 36 hours along the coast from Deerfield Beach, Florida to Edisto Beach, South Carolina; and during the next 48 hours from north of Edisto Beach to South Santee River, South Carolina.

The latest storm surge predictions say if peak surge coincides with high tide, water levels in the following locations could be raised above normal tide levels by as much as:

  • Central and Northwestern Bahamas: 10 to 15 feet
  • Sebastian Inlet to Edisto Beach, including portions of the St. Johns River: 7 to 11 feet
  • Edisto Beach to South Santee River: 4 to 6 feet
  • Deerfield Beach to Sebastian Inlet: 4 to 6 feet
  • Virginia Key to Deerfield Beach: 1 to 3 feet

Here are the updated predictions of total rainfall amounts for each location:

  • The Bahamas: 8 to 12 inches, isolated totals of 15 inches
  • Coastal eastern Florida, Georgia, and South Carolina: 4 to 8 inches, isolated 12 inches
  • The Florida Keys: 1 to 3 inches, isolated 5 inches

In addition, NOAA warns of the likelihood of life-threatening flash floods and mudslides in central and eastern Cuba, and the possibility of tornadoes along the Atlantic coastal area of north and central Florida tonight.

UPDATE (October 5, 5:15 p.m.):  The latest update from NOAA states that hurricane Matthew currently has maximum sustained winds of 120mph, and that “some strengthening is forecast during the next couple of days, and Matthew is expected to remain at category 3 or stronger while it moves through the Bahamas and approaches the east coast of Florida”.

It also warns of the possibility of a combination of storm surge and high tide, which would increase the actual flood levels, and highlights the danger and possibility of life-threatening inundation during the next 36 hours along the Florida east coast from Deerfield Beach to the Flagler/Volusia county line, and during the next 48 hours from north of the Flagler/Volusia county line to the Savannah River.

It gives the following new predictions for storm surge and rainfall:

STORM SURGE

The combination of a dangerous storm surge and large and destructive waves could raise water levels well above normal tide levels. If the peak surge occurs at the time of high tide, the water could reach the following heights above ground.

  • Sebastian Inlet to Savannah River: 5 to 8 feet
  • Deerfield Beach to Sebastian Inlet: 3 to 5 feet
  • Virginia Key to Deerfield Beach.: 1 to 2 feet

In other locations, water levels could rise by as much as the following amounts above normal tide levels:

  • The Bahamas: 10 to 15 feet
  • Northern Coast of Cuba east of Camaguey: 4 to 6 feet

RAINFALL

  • Coastal eastern Florida: 4 to 7 inches, isolated 10 inches
  • Florida Keys: 1 to 3 inches, isolated 5 inches
  • The Bahamas: 8 to 12 inches, isolated 15 inches
  • Eastern Cuba: 8 to 12 inches, isolated 20 inches
  • Central Cuba: 3 to 5 inches, isolated 8 inches
  • Western Haiti: additional 2 to 4 inches, isolated storm totals of 40 inches