Hurricanes are a way of life in Florida. Our state faces the threat of these large and complex storms every summer and fall throughout the hurricane season, which is officially from June 1 to November 30. No two storms are the same and in that fact, each one offers different challenges and threats to the City and its residents. In recent years we have been reminded numerous times of the potentially destructive power of hurricanes, highlighting why everyone must be prepared for them.
With human-induced climate change compounding these already dangerous systems, residents, business owners, and governance must be on watchful guard. Sea level rise will exacerbate storm surge. A warmer atmosphere will allow for more rainfall. Warmer ocean waters will serve to make storms longer lasting, stronger, and will give them the ability to strengthen more quickly.
Fortunately, though we do have warning for these storms with real-time weather forecasting, continuous media coverage, and state of the art weather satellites and other equipment that help to track and observe their every move. We can be prepared. What follows is some hurricane basics and information on how you can be better prepared.
What is a hurricane?
According to the National Hurricane Center, a hurricane is a tropical cyclone in which the maximum sustained surface wind (using the US 1-minute average) is 74 mph (64 kt or 119 km/hr) or more. The term hurricane is used for Northern Hemisphere tropical cyclones east of the International Dateline to the Greenwich Meridian. The term typhoon is used for Pacific tropical cyclones north of the Equator west of the International Dateline.
Hurricanes across the world only form over open warm ocean waters. Environments with moist air and low wind shear (a change in wind direction with height) are also required for their formation. As heat from the sun warms air it rises and condenses into clouds and thunderstorms. This rising motion leaves less air at the surface, forming a low-pressure center. More air rushes into this low-pressure area to try and fill the gap left behind by the rising air, feeding into a cycle. Eventually, this air flow begins to rotate due to the Earth’s rotation. Storms in the Northern Hemisphere rotate counterclockwise. Storms in the Southern Hemisphere rotate clockwise.
As the storm begins to spin faster and faster its structure tightens. A developing system will first be designated a tropical depression or a system that has wind speeds of 38 mph or less. Tropical depressions receive a number for their designation by the National Hurricane Center, not a name. Once the storm surpasses 38 mph it becomes a tropical storm and receives a name. Once the tropical storm is measured to have wind speeds over 73 mph it is designated a hurricane.
Hurricanes can have wind fields hundreds of miles in diameter and deliver feet of rainfall over a very short period of time. It is important when watching an approaching storm that one does not only look at the center forecast track and cone as effects can be felt far from the storm’s center. Hurricanes can also bring storm surge to both coastal and inland areas. Storm surge is a wind-driven water rise where the hurricane’s winds literally push water onto the coast for hundreds of yards, sometimes even miles. Storm surge is the number one killer in a tropical cyclone, so be wary of evacuation orders and storm surge maps for your particular area. Such maps can be found here.
What’s the deal with hurricane categories?
The National Hurricane Center who is responsible for all hurricane tracking in the Atlantic basin uses the Saffir-Simpson Hurricane Wind Scale to measure a hurricane's wind speed and intensity. The scale is as follows:
Each category should not be taken lightly as each one can and have caused significant damage to property and lives. A notable example is 2018's Hurricane Florence, which struck the Carolinas as only a category one hurricane with winds of 80 mph. However, the storm caused an estimated $38 to $50 billion in damages, putting it within the top ten most costly US hurricanes in history, and unfortunately killed over 50 people.
What’s the deal with all those watches and warnings?
The National Hurricane Center uses a system of watches and warnings to alert the general public about when to expect worsening conditions. The chart below shows the differences between hurricane watches and warnings. Tropical storms also receive watches and warnings. The information below is also pertinent to them except instead of hurricane conditions, tropical storm conditions are what to be expected.
What should I do to be prepared?
There are many things you can do to prepare for a tropical system, hurricane or not. Below are several excellent links that can you and your family get ready for an approaching storm. Some of the basics you can cover are:
Having enough supplies to last you and your family at least a week.
Knowing your evacuation route should the need arise.
Signing up for weather alerts on your smart device.
Having enough supplies for your pet(s) for at least a week.
Having a first aid kit and being up to date with all needed medications.
Having the ability to shutter your home or business.
Having a full tank of gas for your car or generator or charging up your electric vehicle.
Have a weather radio.
The following links can be of great help as well when it comes to knowing what to do before, during, and after a storm, as well as receiving relevant and up to date storm information. Be careful of misinformation regarding these storms from non-official sources and only consult hurricane forecast from the National Hurricane Center.