Tropical Cyclones

A tropical cyclone is a rotating, organized system of clouds and thunderstorms that originates over tropical or subtropical waters and has a closed low-level circulation. Tropical cyclones rotate counterclockwise in the Northern Hemisphere. They are classified as follows:

Tropical Depression: A tropical cyclone with maximum sustained winds of 38 mph (33 knots) or less.
Tropical Storm: A tropical cyclone with maximum sustained winds of 39 to 73 mph (34 to 63 knots).
Hurricane: A tropical cyclone with maximum sustained winds of 74 mph (64 knots) or higher. In the western North Pacific, hurricanes are called typhoons; similar storms in the Indian Ocean and South Pacific Ocean are called cyclones.
Major Hurricane: A tropical cyclone with maximum sustained winds of 111 mph (96 knots) or higher, corresponding to a Category 3, 4 or 5 on the Saffir-Simpson Hurricane Wind Scale.

North Carolina is especially vulnerable to direct tropical cyclone strikes because the coastline extends out into the ocean. Heavy winds, tornadoes, flooding, and storm surges can all be caused by hurricanes, causing billions of dollars in damage.

All tropical cyclones should be taken very seriously regardless of the category. Although categories of hurricanes are determined by wind speed, most damage occurs from flooding so wind speed alone does not determine the severity of a storm. Hurricane Florence, which made landfall in Wrightsville Beach in 2018 as a category one hurricane, caused $24 billion in damages; more than the cost of Hurricane Matthew (2016) and Hurricane Floyd (1999) combined.

If New Hanover County's Emergency Operations Center (EOC) is activated due to a hurricane or other emergency event, emergency information and instructions will be provided.

ReadyNHC: Make a Plan, Build a Kit, Stay Informed

what is the cone of uncertainty?

The cone represents the probable track of the center of a tropical cyclone, and is formed by enclosing the area swept out by a set of circles along the forecast track (at 12, 24, 36 hours, etc). It assesses the official forecast errors over the previous 5 years and notes where 2/3 of those errors fell. This means that 2/3 of the time (60%-70%), the storm should stay within the area of the cone...ANYWHERE within the area of the cone. But, it also means that 1/3 of the time, the storm could move outside of the left side of the cone or the right side of the cone.

In our example of the anticipated track of Hurricane Laura:

The dots in the middle of the cone represent the strength of the storm and when the storm might reach that strength at that point in the forecast. It does NOT pinpoint the center of the storm or indicate the exact track of the storm.
The center of the storm could be ANYWHERE in the white portion of the cone. 60% to 70% of the time, the center of the storm will stay in that general area of the cone.
One-third of the time, the storm could be to the left or to the right of the cone.
In all instances, impacts of the storm can be felt WELL outside of the cone all together.
You should use the cone as an awareness tool. When you see that a storm might impact your region, you should, at a minimum, review your plans and check your emergency kits. If the storm moves and does not impact you, you'll know your resources are ready; if it does hit you, you'll be ready to go and protect you and your family.

DO NOT USE THE CONE ALONE, OR THE LINE IN THE MIDDLE OF THE CONE, AS AN INDICATOR TO WHERE DAMAGE WILL BE LIMITED TO DURING A STORM.

It is important to note that winds, rain, storm surge, and damage can occur WELL outside of the white part of the cone. Check out this video for info from the National Hurricane Center on how to use this information to help keep your family safe during the next storm.

what is storm surge?

Storm surge is an extremely dangerous hazard associated with hurricanes and tropical storms. Storm surge happens when wind from a storm drives water onshore, causing an unusual and rapid rise in water level. Larger, stronger storms typically produce the greatest storm surge flooding. Storm surge occurs in addition to the normal tides, so coastal storm surge flooding is worst during high tide.

Storm surge can raise the water level several feet or more, causing flooding in normally dry areas many miles from the shore, especially in low-lying coastal areas. Moving water is an incredibly powerful force. Just one foot of water can carry a small car, but during storm surge, many feet of water can move onshore. The force of this water can not only carry cars, but can completely sweep houses and buildings off of their foundations. As a result, damage from storm surge can be catastrophic.

Learn your risk for storm surge and review the National Hurricane Center storm surge hazard maps.

Storm surge can reach many miles from a coast in low-lying areas. Rivers inland from the ocean can also be subject to storm surge. Visit Know Your Zone to enter your address and see what evacuation zone you live in.

What is a rip current?

Strong winds from tropical storms and hurricanes can cause rip currents. Rip currents and high surf can be deadly, even when storms are hundreds of miles offshore, sometimes days before a hurricane makes landfall. The storm may not be headed to impact us at all, and passing well to our east.

Do not travel to the beach to surf, swim, or loiter. Pay attention to signs on the beach and guidance from local officials and lifeguards. Click here to see an aerial rip current video from Wrightsville Beach.

What's a watch versus a Warning?

Tropical Strom Watch: Tropical storm conditions (sustained winds of 39 to 73 mph) are possible somewhere within the specified area within 48 hours.

Tropical Storm Warning: Tropical storm conditions (sustained winds of 39 to 73 mph) are expected somewhere within the specified area within 36 hours.

Hurricane Watch: Hurricane conditions (sustained winds of 74 mph or greater) are possible somewhere within the specified area.

Hurricane Warning: Hurricane conditions (sustained winds of 74 mph or greater) are expected somewhere within the specified area. Evacuate immediately if so ordered.

Storm Surge Watch: There is a possibility of life-threatening storm surge flooding from rising water moving inland somewhere within the specified area, generally within 48 hours.

Storm Surge Warning: There is a danger of life-threatening storm surge flooding from rising water moving inland somewhere within the specified area, generally within 36 hours. If you are under a storm surge warning, check for evacuation orders from your local officials.

A easy way to think about it is to think of cupcakes.

(Photo credit Brad Panovich, Meterologist)

You've decided you want cupcakes and you say "I think I want cupcakes sometime later today." That's a statement or advisory.
You visit the store and buy all of the ingredients to make cupcakes. You have them all measured out and ready, the cupcake foils are in the tins, the oven is warming up, and you follow the recipe. That's a watch.
You have successfully made and frosted the cupcakes and are ready to eat them! All of the ingredients came together to make the richest most delicious cupcake. That's a warning.

What should I do if there is a tropical cyclone or storm surge watch or warning?

When a Storm Is 36 Hours From Arriving

Bookmark Emergency Information and check the page frequently for storm updates and emergency instructions from county officials. The latest weather forecast and emergency information will also be available on TV and the radio.
Plan how to communicate with family members if you lose power. Identify an out-of-town contact, and try to send texts instead of calling as texts can be faster than making phone calls when lines are overloaded.
Restock your emergency supply kit. Include food and water sufficient for seven to ten days for each family member, medications, a flashlight, batteries, cash, and first aid supplies.
Stay informed
- Check Emergency Information frequently for updates from county officials
- Register for emergency alerts by phone, text, or email
- Sign up for New Hanover County emergency news updates
- Subscribe to National Weather Service updates
- Follow New Hanover County on Facebook, Twitter, and YouTube
- Download the ReadyNC app
- National Oceanic and Atmospheric Administration (NOAA) Weather Radio
Know the types of flood risks in your area.
Review your evacuation routes and shelter locations. You may have to leave quickly so plan ahead.
Make sure your car is in good working condition, and keep the gas tank full; stock your vehicle with emergency supplies and a change of clothes.
If you have flood insurance, check your policy to see if loss avoidance measures are covered. National Flood Insurance Program (NFIP) policies cover the cost of loss avoidance measures, like sandbags and water pumps, to protect your insured property. Keep copies of all receipts and a record of the time spent performing the work to submit to your flood insurance adjuster for reimbursement. Learn more about Flood Loss Avoidance on FEMA's website.

When a Storm Is 18 to 36 Hours From Arriving

Continue to check Emergency Information often and turn on your TV and / or radio to get the latest weather updates and emergency instructions.
Bring loose, lightweight objects inside that could become projectiles in high winds (such as patio furniture, garbage cans); anchor objects that would be unsafe to bring inside (such as propane tanks); trim or remove trees close enough to fall on your house.
If possible, cover all of your home's windows. Although permanent storm shutters offer the best protection for windows, another option is to board up windows with 5/8 inch exterior grade or marine plywood, cut to fit and ready to install.
If encouraged by local officials, plan to evacuate.

When a Storm Is 6 to 18 Hours From Arriving

Continue checking Emergency Information frequently and turn on your TV and / or radio to get the latest weather updates and emergency instructions.
Charge your cell phone so you will have a full battery in case you lose power.

When a Storm Is 6 Hours From Arriving

If you are not in an area that is recommended for evacuation, plan to stay at home or where you are, and share your location with friends and family.

Close storm shutters and stay away from windows. Flying glass from broken windows could injure you.

Turn your refrigerator or freezer to the coldest setting and open only when necessary so that if you lose power, food will last longer. Keep a thermometer in the refrigerator to be able to check the food temperature when the power is restored.

Turn on your TV or radio, and check Emergency Information every 30 minutes in order to get the latest weather updates and emergency instructions.

Prepare before a tropical cyclone

Most importantly, you need to know what your local hazards are. Find out if you live in an evacuation zone so you are ready to follow evacuation orders. Learn whether storm surge is a risk in your area (even if you are inland).

Develop an Evacuation Plan

If you live in an evacuation zone, determine how you will evacuate and where you will go if an evacuation order is issued. How will you get to your destination? Be sure to plan an alternate route! How can you take care of your pets? You don’t necessarily need to travel hundreds of miles to be safe, but always make sure your evacuation destination provides protection from hurricane hazards, like inland flooding near a river, creek, or dam or mudslides.

Assemble Disaster Supplies

Devastating hurricanes can lead to long recovery times. Be prepared with at least three days of supplies (or more!) including water, non-perishable food, medicine, and pet supplies. Extra cash, a battery-powered radio, flashlights, and a portable crank or solar powered USB charger to charge your cell phone are also important. These supplies are helpful in any disaster, not just a hurricane, so it is always a good idea to have them on hand.

Get an Insurance Checkup

Check with your insurance agency before hurricane season to learn what is covered. Homeowners insurance does not cover flooding. Flood insurance requires a separate policy for both owners and renters and it takes 30 days to kick in. Learn more about the National Flood Insurance Program.

Strengthen Your Home

You can take steps to make your home more resilient to threats from a hurricane. Purchase plywood, steel, or aluminum panels to board up windows and doors and have them on hand. Keep your trees trimmed. Secure loose outdoor items and furniture and find a safe place for your car.

Help Your Neighbor

Get to know your neighbors and their needs. Many people, especially senior citizens, may need help from neighbors before, during, and after hurricanes.

Once you have made all of these preparations, write them down! It’s easy to forget something you planned far in advance. Store your written plan somewhere safe, have photo documentation of valuables, and share your plan with your family.

survive during a tropical cyclone

As a storm approaches, always pay attention to evacuation orders and other information from New Hanover County at www.emergency.nhcgov.com Follow evacuation orders when they are issued. Help may be delayed during and following a storm, so preparation for and awareness of evacuation orders is key.

If your local area is under a hurricane warning and you choose to stay in the area:

Be prepared to shelter in an interior portion of your home. Get as far away from windows and doors as possible. The more walls you can put between you and the outside, the better.
Never go outside during the calm period when the eye of the storm passes. The eyewall is the most dangerous part of a hurricane and can come on suddenly.
Stay out of flooded areas. Just six inches of water can knock an adult off their feet and flood waters can carry disease.
Keep your battery operated radio and a flashlight or camping lantern nearby. You will need them!
Be aware of the possibility of flooding and tornadoes.

Stay safe after a tropical cyclone

There are many hazards that follow a hurricane that can lead to indirect deaths or injuries.

Overexertion is especially dangerous. Following a hurricane, people may want to clean up immediately, but overexertion can lead to heart attacks, heat strokes, and other serious medical issues. Perform cleanups safely and slowly. Be sure to take lots of breaks and not push beyond your limits.
Generator accidents are very common following a hurricane that caused power outages. Familiarize yourself with generator safety if you think you may use one. Carbon monoxide poisoning, electric shock, and fire are the most common hazards,
Power tools, like chainsaws, that are used during cleanup can lead to accidents and death. If you are not trained to use them, leave the power tools to the experts.
Turn Around, Don't Drown - Flooding can still be a major hazard weeks after a hurricane passes, even when evacuation orders may have expired and wind is no longer a threat. Any body of water — a lake, river, stream, or pond, including ones that are inland — is at risk of flooding during a hurricane or tropical storm. The ground may already be saturated with water if there has been heavy rains before the storm, meaning an even higher likelihood of flooding. Flooded roads are very dangerous. It can be difficult to judge how deep or swift the water is moving — just 12 inches of water can float a car. Never drive through flooded roads, even if you are seeking supplies or trying to check on someone. Floods can also compromise bridges and roads. Avoid flooded river areas, as they can continue to rise long after a storm passes. Always keep a safe distance from flooded and damaged areas. Never drive through floodwaters or compromised bridges. Always pay attention to barriers and signage. If you encounter flooding, remember: Turn Around Don’t Drown.
Listen to local authorities for information and special instructions. Continue checking online or weather radio for updates.
Do not touch electrical equipment if it is wet or if you are standing in water. If it is safe to do so, turn off electricity at the main breaker or fuse box to prevent electric shock.
Avoid wading in flood water, which can contain dangerous debris and bacteria. Underground or downed power lines can also electrically charge the water.
Practice good hygiene after contact with flood water, and do not allow children to play in flood water. Learn more about flood water safety.
Save phone calls for emergencies. Phone systems are often down or busy after a disaster. Use text messages or social media to communicate with family and friends.
Document any property damage with photographs. Contact your insurance company for assistance.