Hurricane Prepardness Guide
What is a Hurricane?
A hurricane is a type of tropical cyclone, the general term for all circulating weather systems over tropical waters (counterclockwise in the Northern Hemisphere). Tropical cyclones are classified as follows:
- Tropical Depression: An organized system of clouds and thunderstorms with a defined circulation and maximum sustained winds of 38 mph (33 knots) or less.
- Tropical Storm: An organized system of strong thunderstorms with a defined circulation and maximum sustained winds of 39 to 73 mph (34-63 knots).
- Hurricane: An intense tropical weather system with a well defined circulation and maximum sustained winds of 74 mph (64 knots) or higher. In the western Pacific, hurricanes are called "typhoons," and similar storms in the Indian Ocean are called "cyclones."
Hurricanes are products of a tropical ocean and atmosphere. Powered by heat from the sea, they are steered by the easterly trade winds and the temperate westerlies as well as by their own ferocious energy. Around their core, winds grow with great velocity, generating violent seas. Moving ashore, they sweep the ocean inward while spawning tornadoes and producing torrential rains and floods. Each year, on average, 10 tropical storms, of which six become hurricanes, develop over the Atlantic Ocean, Caribbean Sea, or Gulf of Mexico. Many of these remain over the ocean; however, about five hurricanes strike the United States coastline every three years. Of these five, two will be major hurricanes, category 3 or greater on the Saffir-Simpson Hurricane Scale.
Timely warnings have greatly diminished hurricane fatalities in the United States and the Caribbean region. In spite of this, property damage continues to mount. There is little we can do about the hurricanes themselves. However, National Hurricane Center and National Weather Service field offices team up with Office Of Disaster Prepardness & Emergency Management (ODPEM) and local agencies; rescue and relief organizations; the private sector; and the news media in a huge warning and preparedness effort.
Breeding Grounds
In the eastern Pacific, hurricanes start forming by mid-May. In the Atlantic, Caribbean, and Gulf of Mexico, hurricanes season starts in June. For the United States, peak hurricane threat exists from mid-August to late October although the official hurricane season extends through November. Over other parts of the world, such as the western Pacific, hurricanes can occur year-round.
Developing hurricanes gather heat and energy through contact with warm ocean waters. The addition of moisture by evaporation from the sea surface powers them like giant heat engines.
Storm Structure
The process by which a disturbance forms and subsequently strengthens into a hurricane depends on at least three conditions. Warm waters and moisture are mentioned above. The third condition is a wind pattern near the ocean surface that spirals air inward. Bands of thunderstorms form, allowing the air to warm further and rise higher into the atmosphere. If the winds at these higher levels are relatively light, this structure can remain intact and allow for additional strengthening.
The center, or eye, of a hurricane is relatively calm. The most violent activity takes place in the area immediately around the eye, called the eyewall. At the top of the eyewall (about 50,000 feet), most of the air is propelled outward, increasing the air's upward motion. Some of the air, however, moves inward and sinks into the eye, creating a cloud-free area.
Storm Fury
Storm Surge
Storm surge is a large dome of water often 50 to 100 miles wide that sweeps across the coastline near where a hurricane makes landfall. The surge of high water topped by waves is devastating. The stronger the hurricane and the shallower the offshore water, the higher the surge will be. Along the immediate coast, storm surge is the greatest threat to life and property.
Storm Tide
If the storm surge arrives at the same time as the high tide, the water height will be even greater. The storm tide is the combination of the storm surge and the normal astronomical tide. For example as hurricane moves ashore, a 15-foot surge added to the normal 2-foot tide creates a storm tide of 17 feet. This mound of water, topped by battering waves, moves ashore along an area of the coastline as much as 100 miles wide. The combination of the storm surge, battering waves, and high winds is deadly.
Tornadoes
Hurricanes also produce tornadoes, which add to the hurricane's destructive power. These tornadoes most often occur in thunderstorms embedded in rain bands well away from the center of the hurricane. However, they can also occur near the eyewall.
Perception of Risk
Over the past several years, the warning system has provided adequate time for people on the barrier islands and the immediate coastline to move inland when hurricanes have threatened. However, it is becoming more difficult to evacuate people from the barrier islands and other coastal areas because roads have not kept pace with the rapid population growth. The problem is further compounded by the fact that 80 to 90 percent of the population now living in hurricane-prone areas have never experienced the core of a "major" hurricane. Many of these people have been through weaker storms. The result is a false impression of a hurricane's damage potential. This often leads to complacency and delayed actions which could result in the loss of many lives.
Surveillance and Forecasting
Satellite
Geostationary satellites orbiting the earth at an altitude of about 22,000 miles above the equator provide imagery both day and night. The satellite imagery helps provide estimates of the location, size, and intensity of a storm and its surrounding environment.
HURRICANE WATCH: Hurricane conditions are possible in the specified area of the Watch, usually within 36 hours. During a Hurricane Watch, prepare to take immediate action to protect your family and property in case a Hurricane Warning is issued. HURRICANE WARNING: Hurricane conditions are expected in the specified area of the Warning, usually within 24 hours. Complete all storm preparations and evacuate if directed by local officials. SHORT TERM WATCHES AND WARNINGS: These provide detailed information on specific hurricane threats, such as tornadoes, floods, and high winds. All of the above information must be used to make an informed decision on your risk and what actions should be taken. Remember to listen to release's from Office Of Disaster Preparedness And Emergency Management (ODPEM) recommendations and to your Radio Stations for the latest hurricane information.
Personal and Community Preparedness
Before the Hurricane Season
- Know the hurricane risks in your area.
- Learn safe routes inland.
- Learn location of official shelters.
- Ensure that enough non-perishable food and water supplies are on hand.
- Obtain and store materials, such as plywood, necessary to properly secure your home.
- Clear loose and clogged rain gutters and downspouts.
- Keep trees and shrubbery trimmed.
- Review your insurance policy.
Individuals with special needs or others requiring more information should contact their local National Weather Service office, emergency management office, or American Red Cross chapter.
During the Storm
When in a Watch Area...
- Frequently listen to radio, TV, for latest Weather update. progress.
- Fuel and service family vehicles.
- Inspect and secure mobile home tie downs.
- Prepare to cover all window and door openings with shutters or other shielding materials.
- Check batteries and stock up on canned food, first aid supplies, drinking water, and medications.
- Prepare to bring inside lawn furniture and other loose, light-weight objects, such as garbage cans, garden tools, etc.
- Have on hand an extra supply of cash.
Plan to evacuate if you...
- Live in a mobile home. They are unsafe in high winds, no matter how well fastened to the ground.
- Live on the coastline, an offshore island, or near a river or a flood plain.
- Live in a high-rise. Hurricane winds are stronger at higher elevations.
When in a Warning Area...
- Closely monitor radio, TV, and ODPEM for official bulletins.
- Complete preparation activities, such as putting up storm shutters, storing loose objects, etc.
- Follow instructions issued by local Disaster Preparedness officials. Leave immediately if told to do so!
- If evacuating, leave early (if possible, in daylight). Stay with friends or relatives, at a low-rise inland hotel/motel, or go to a predesignated public shelter outside a flood zone.
- Leave mobile homes in any case.
- Notify neighbors and a family member outside of the warned area of your evacuation plans.
- Put food and water out for a pet if you cannot take it with you. Public health regulations do not allow pets in public shelters, nor do most hotels/motels allow them.
What to bring to a shelter: first-aid kit; medicine; baby food and diapers; cards, games, books; toiletries; battery-powered radio; flashlight (one per person); extra batteries; blankets or sleeping bags; identification, valuable papers (insurance), and cash.
If you ARE told to leave, do so immediately!
If Staying in a Home...
Only stay in a home if you have NOT been ordered to leave. Stay inside a well constructed building. In structures, such as a home, examine the building and plan in advance what you will do if winds become strong. Strong winds can produce deadly missiles and structural failure.
- Turn refrigerator to maximum cold and open only when necessary.
- Turn off utilities if told to do so by authorities.
- Turn off propane tanks.
- Unplug small appliances.
- Fill bathtub and large containers with water for sanitary purposes.
If winds become strong...
- Stay away from windows and doors even if they are covered. Take refuge in a small interior room, closet, or hallway.
- Close all interior doors. Secure and brace external doors.
- If you are in a two-story house, go to an interior first-floor room, such as a bathroom or closet.
- If you are in a multiple-story building and away from the water, go to the first or second floors and take refuge in the halls or other interior rooms away from windows.
- Lie on the floor under a table or another sturdy object.
- TORNADOES which often are spawned by hurricanes.
- The calm "EYE" of the storm. After the eye passes, the winds will change direction and quickly return to hurricane force.
After the Storm
- Keep listening to radio, TV, or ODPEM update.
- Wait until an area is declared safe before entering.
- Roads may be closed for your protection. If you come upon a barricade or a flooded road, turn around and go another way!
- Avoid weakened bridges and washed out roads. Do not drive into flooded areas.
- Stay on firm ground. Moving water only 6 inches deep can sweep you off your feet. Standing water may be electrically charged from under-ground or downed power lines.
- Check gas, water, and electrical lines and appliances for damage.
- Do not drink or prepare food with tap water until you are certain it is not contaminated.
- Avoid using candles and other open flames indoors. Use a flashlight to inspect for damage.
- Use the telephone to report life-threatening emergencies only.
- Be especially cautious if using a chainsaw to cut fallen trees.
Community Preparedness Plans
Each community subject to a hurricane threat should develop its own hurricane safety plan. After you have developed a personal/family safety plan, you may want to find out about your community safety plan. Your local officials should have the most detailed information for your immediate area. Please listen to and follow their recommendations both before, during, and after the storm.
FAMILY DISASTER PLAN
Families should be prepared for all hazards that could affect their area. The Office Of Disaster Prepardness & Emergency Management (ODPEM) urges every family to develop a family disaster plan.
Where will your family be when disaster strikes? They could be anywhere at work, at school, or in the car. How will you find each other? Will you know if your children are safe? Disaster may force you to evacuate your neighborhood or confine you to your home. What would you do if basic services water, gas, electricity or telephones were cut off?
Follow these basic steps to develop a family disaster plan...
I. Gather information about hazards. The Office Of Disaster Prepardness & Emergency Management (ODPEM). Find out what type of disasters could occur and how you should respond. Learn your community's warning signals and evacuation plans.
II. Meet with your family to create a plan. Discuss the information you have gathered. Pick two places to meet: a spot outside your home for an emergency, such as fire, and a place away from your neighborhood in case you can't return home. Choose an out-of-state friend as your "family check-in contact" for everyone to call if the family gets separated. Discuss what you would do if advised to evacuate.
III. Implement your plan. (1)Post emergency telephone numbers ;
(2) Install safety features in your house, such as smoke detectors and fire extinguishers;
(3) Inspect your home for potential hazards (such as items that can move, fall, break, or catch fire) and correct them;
(4) Have your family learn basic safety measures, such as CPR and first aid; how to use a fire extinguisher; and how and when to turn off water, gas, and electricity in your home;
(5) Teach children how and when to call 110, 119 or your local Emergency Medical Services number;
(6) Keep enough supplies in your home to meet your needs for at least three days. Assemble a disaster supplies kit with items you may need in case of an evacuation. Store these supplies in sturdy, easy-to-carry containers, such as backpacks or duffle bags. Keep important family documents in a waterproof container. Keep a smaller disaster supplies kit in the trunk of your car.
A Disaster Supplies Kit Should Include:
- A 3-day supply of water (one gallon per person per day) and food that won't spoil
- one change of clothing and footwear per person
- one blanket or sleeping bag per person
- a first-aid kit, including prescription medicines
- emergency tools, portable radio, flashlight, and plenty of extra batteries
- an extra set of car keys and a credit card or cash
- special items for infant, elderly, or disabled family members.
IV. Practice and maintain your plan. Ask questions to make sure your family remembers meeting places, phone numbers, and safety rules. Conduct drills. Test your smoke detectors monthly and change the batteries two times each year. Test and recharge your fire extinguisher(s) according to manufacturer's instructions. Replace stored water and food every 6 months. Contact Office Of Disaster Prepardness & Emergency Management (ODPEM). or local office.