Community Corner

A Primer on Hurricanes

How they are measured, a history of some of the worst and more.

Here is a primer on hurricanes, including interesting hurricane facts, an explanation of the Saffir-Simpson scale, descriptions of some of the most devastating hurricanes in recent history, and a guide to how you and your family should prepare in case of a hurricane.

What IS a hurricane?

A hurricane is a storm with sustained wind speed of at least 74 miles per hour.

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A tropical storm has wind speeds of 39 to 73 mph. A tropical depression is a storm with a wind speed of 38 mph.

The anatomy of a hurricane

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To have a hurricane, you have to have warm water; this is why hurricanes only happen in the summer.

Hurricanes are started by tropical depressions over water that’s at least 80 degrees. Air from surrounding areas with higher air pressure pushes in to these low-pressure areas, then that “new,” cooler air becomes warm and moist and rises. As that warm air rises, more new, cooler air feeds in to take its place. Eventually, when it rises high enough, the warm air cools, forming clouds, and sinking. The warmth of the ocean, and the water evaporating from its surface continues to rise and swirl, forming the hurricane.

 A typhoon is a hurricane in the Pacific.

The word “hurricane” comes from the Taino Native American word, hurucane, meaning “evil spirit of the wind,” according to HurricaneFacts.com.

The planet Jupiter has a hurricane that's been going on for more 300 years, according to HurricaneFacts.com. It can be seen as a red spot on the planet. This hurricane on Jupiter is bigger than the Earth itself.

Measurement

Hurricanes are measured 1 to 5 on the Saffir-Simpson scale. The scale, according to the National Weather Service, was developed by Herb Saffir, a wind engineer, and Bob Simpson, a meteorologist.

While the scale makes references to wind speed, it’s really concerned with the type of damage that winds at particular speeds will create – in other words, intensity, which is not always a direct link to wind speed.

The Scale

Category 1

Sustained winds of 74-95 mph. “Very dangerous winds will produce some damage.”

“People, livestock and pets struck by flying or falling debris could be injured or killed,” the description says. A Category 1 hurricane could destroy older mobile homes and damage newer ones and poorly built houses. Well-built homes could have damage to shingles, siding, gutters and  soffit panels.

Commercial signs will be damaged, large branches of trees will break and shallow-rooted trees could fall.

Hurricane Dolly, in South Padre Island, Texas, in 2008, was a Category 1 hurricane.

Category 2

Sustained winds of 96-110 mph. “Extremely dangerous winds will cause extensive damage.”

“Substantial risk of injury or death to people, livestock and pets.”

Mobile homes built before 1994 will probably be destroyed, as will some newer ones, and some poorly built homes. Porches and gables of well-built homes could be damaged. Unreinforced masonry walls will collapse. Shallow trees will be snapped or uprooted, roads will be blocked, and power will be lost, with outages that could last from days to weeks.

Hurricane Frances, in 2004, was a Category 2 storm.

Category 3

Sustained winds of 111-130 mph. “Devastating damage will occur.”

“High risk of death or injury to people, livestock and pets due to flying and falling debris.”

Nearly all mobile homes built before 1994 will be destroyed. Most newer ones will suffer severe damage. Poorly built frame homes will be wrecked. Unprotected windows will be broken by flying debris. Well-built homes will be damaged, older metal buildings will fail.

Hurricane Ivan, in 2004, was a Category 3 storm.

Category 4

Sustained winds of 131-155 mph. “Catastrophic damage will occur.”

Very high risk of injury or death to people, livestock and pets. In addition to all of the above, well-built homes will lose most of their roofs and exterior walls. Top floors of apartment buildings will be damaged, most windows will be blown out of high-rise buildings, and fallen trees and wires will isolate residential areas. Power outages will last for weeks or months, and most of the area will be uninhabitable. Hurricane Charley, in 2004, was a Category 4 storm.

Category 5

Sustained winds greater than 155 mph. “People, livestock and pets are at very high risk of injury or death from flying debris, even indoors in mobile homes or frame homes.”

Almost complete destruction of all mobile homes, regardless of how new they are or how well built they are. Many frame homes will be destroyed. Nearly all unprotected windows, and many protected ones, will be destroyed. Nearly all trees will be snapped or uprooted. Power outages will last for weeks or months, and most of the area will be uninhabitable.

To read the entire descriptions, click on the pdf in the photo box. 

Some of the storms

In Maryland -

HURRICANE HAZEL Mid-October in 1954, brought sustained winds of 78 MPH and gusts near 100 MPH were reported around the Chesapeake Bay and on the Eastern Shore.

HURRICANES CONNIE AND DIANE arrived back-to-back in August of 1955. The storms sunk the schooner Levin J Marvel and 14 passengers drowned.

HURRICANE AGNES came in June of 1972, and is still to date one of the most destructive natural disasters in history, roads were destroyed by floods and thousands of people were evacuated.

HURRICANE GLORIA - The September 1985 storm stayed off shore, but caused severe damage in Ocean City.

HURRICANE FLOYD in September 1999 brought more than 10 inches of rain to the areas along the Eastern Shore, including 11.6 inches in Annapolis City.

HURRICANE ISABEL brought widespread power outages that lasted in some places more than a week. The storm, which raged for nine hours created extreme coastal flooding throughout the Chesapeake Bay region.

Elsewhere -

THE GREAT GALVESTON HURRICANE - The hurricane that hit Texas in 1900, was the deadliest hurricane recorded in the United States. It killed at least 6,000 people. The National Weather Service calls it the greatest natural disaster ever to strike the U.S.

There were storm warnings, and they saved thousands of people, according to a report by Isaac M. Cline, local forecast official and section director. Click here to read his entire, fascinating account of the storm. At one point in the storm, he says, the water rose 4 feet in four minutes.

HURRICANE KATRINA

Katrina was the most devastating hurricane in recent American history. It hit Louisiana on Aug. 29, 2005, as a Category 3 storm, killing nearly 2,000 people, and causing $200 billion in damages. New Orleans and the surrounding areas have still not yet recovered.

HURRICANE ANDREW

Andrew, which hit the U.S. in August, 1992, was “a small and ferocious Cape Verde hurricane,” according to the National Weather Service, that created terrible and unprecedented economic devastation through the Bahamas, the southern peninsula of Florida and south central Louisiana. The nearly $25 billion in damage in the United States made Andrew the most expensive natural disaster in U.S. history, at that time. In Dade County, FL, 15 people died, and as many as 250,000 were left homeless

For more

To read about more devastating hurricanes, click here.

What to do

Editor's note: For more on preparing for hurricanes, see: "

Make a family emergency plan.

First, identify an out-of-town contact whom everyone can call. This person can be the keeper of information for you and your family, keeping track of who is where and what is needed.

Be sure everyone knows the number, and has a cell phone, coins for a payphone, or a prepaid phone care.

Ready.gov says the program that person into your phone as ICE – in Case of Emergency. Emergency personnel will often look for this listing in your phone. Be sure to alert the person you’ve chosen.

The site also says to be sure that everyone knows how to send text messages. These can often get through when phone calls can’t.

Subscribe to alert services. Many communities have them; sign up by visiting your local Office of Emergency Management web site.

Evacuations

You might be forced to leave your home during Hurricane Irene. If you are told to go, go. Make plans with your family about where you will go and how you will meet up.

Emergency Plans

Ready.gov has an online emergency planning tool. Click here to reach it, then use the Quick Share application (click here) to share the information with your family and friends.

Have a plan ready, in case you get separated.

Prepare your home

While you might or might not choose to put plywood on your windows, there are many other tasks that you should do before the storm hits.

Put away everything that could be tossed about by high winds. Imagine a 90-mph wind and what it might pick up and hurl toward you, your cars, your house.

Items to put away might include: 

  • Garden tools that you’ve left leaning against the house
  • Porch furniture, including tables
  • Grills
  • Ladders
  • Building materials
  • Lawn ornaments
  • Windchimes
  • Window boxes

If you have not cleaned your gutters recently, clean them now.

Also, make sure that any loose siding or roofing, any loose shutters or decking is secured.

Water

Buy or bottle plenty of water for drinking. Fill your bathtubs with water for flushing toilets.

Food

Have on hand food that you can eat without cooking. Power could be out for days, so be prepared. Don’t count on being able to buy anything at the grocery store after the storm.

Medicine

Make sure your prescriptions are filled, and that if you leave the house, you take them with you.

Lights

Have candles, kerosene lanterns, flashlights, camplights, etc. Be sure you have batteries for all these items, and that they are working.

Information

You can buy radios that work on batteries, or solar, or which can be hand-cranked. These will be your best source of information if the power is out, so you might want to invest in one. Remember that you can also use your car radio.

Pets

Have a plan for your pets. Some shelters will take pets, but they must be in crates. Other shelters will not accept animals. Check with your town. If your pets are on medicine, make sure that it accompanies them wherever they go.

Money

Get cash. If the power goes out, ATMs will not be working, and banks might very well not be open.

Cars

Make sure the cars are running well, and are parked in a place where falling trees will not hit them. Fill up the gas tanks. If the power is out, gas pumps will not work.

Valuables

If you have a safe-deposit box, now is the time to store your valuable jewelry and papers.

Mementos

“If I lose that, I will be heartbroken.” If you feel this way about anything, take it with you, or put it in a safe place now. The photographs and scrapbooks in the basement, the vase from your grandmother, the kids’ report cards and baby shoes – if you honestly can’t live without them, get them somewhere safe before the storm hits. Anyone who has lived through a flood or hurricane or other disaster will tell you that it’s losing this stuff that hurts most.


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