What is a Hurricane? Hurricane Basics

  • Sep 06, 2017

What is a Hurricane?

The first thing to understand about hurricanes is what they really are. Hurricanes are enormous storms that form over water and move toward land in the Western Hemisphere. These storms have wind speeds greater than tropical depressions and tropical storms. To be classified as a hurricane, a storm must have sustained winds higher than 74 mph.

Common threats from hurricanes include:

  • High winds
  • Heavy rainfall
  • Storm surge
  • Flooding
  • Rip currents
  • Tornadoes


These large storms are called typhoons in the North Pacific Ocean and cyclones in other parts of the world.

Where Do Hurricanes Happen?

Now that we’ve answered “What is a hurricane,” you might be wondering where these storms often occur. Each year, many parts of the United States experience heavy rains, strong winds, floods, and coastal storm surges from tropical storms and hurricanes. Affected areas include all Atlantic and Gulf of Mexico coastal areas and areas over 100 miles inland, Puerto Rico, the U.S. Virgin Islands, Hawaii, parts of the Southwest, the Pacific Coast, and the U.S. territories in the Pacific. A significant

Affected areas include:

  • All Atlantic and Gulf of Mexico coastal areas and areas over 100 miles inland
  • Puerto Rico
  • The U.S. Virgin Islands
  • Hawaii
  • Parts of the Southwest
  • The Pacific Coast
  • U.S. territories in the Pacific


Hurricane Season

Hurricanes don’t happen throughout the year. Instead, there is a defined hurricane season. The Atlantic hurricane season runs from June 1 to November 30. The peak of the season occurs between mid-August and late November. The Eastern Pacific hurricane season begins May 15 and ends November 30.

How Do I Know if a Hurricane is Approaching?

You’ll know when a hurricane is approaching based on watches and warnings. The National Weather Service in the United States has four main watches and warnings related to tropical storms.

Tropical Storm Watch

The first is a Tropical Storm Watch. Tropical Storm Watches are issued when a tropical cyclone containing winds of 39 to 73 mph or higher poses a possible threat to an area. This threat is generally within 48 hours. These winds may be accompanied by storm surge, coastal flooding, and./or river flooding.

It’s important to note that a watch does not mean that tropical storm conditions will occur. It only means that these conditions are possible.

Tropical Storm Warning

The second is a Tropical Storm Warning. A Tropical Storm Warning is issued when sustained winds of 39 to 73 mph or higher associated with a tropical cyclone are expected in 36 hours of less. These winds may also be accompanied by storm surge, coastal flooding, and/or river flooding.

Hurricane Watch

The third is a hurricane watch. A Hurricane Watch is issued when a tropical cyclone containing hurricane force winds (74 mph or higher) poses a possible threat, generally, within 48 hours. These winds may also have storm surge coastal flooding, and/or river flooding happening at the same time.

Like a Tropical Storm Watch, a Hurricane Watch does not mean that hurricane conditions will occur, only that they are possible.

Hurricane Warning

The fourth and most urgent is a hurricane warning. A Hurricane Warning is issued when sustained winds of 74 mph or higher associated with a tropical cyclone are expected in 36 hours or less. These winds may be accompanied by the dangerous conditions listed above. A Hurricane Warning can remain in effect when dangerously high water or a combination of dangerously high water and exceptionally high waves continue, even though winds may be less than hurricane force.

Real-Time Weather Data

On top of paying attention to hurricane watches and warnings, businesses can also rely on real-time weather data visualization. This type of advanced weather tool allows decision-makers to monitor over 40 layers of real-time weather data to help them understand not only a hurricane’s category and track but the other conditions that come with it. If you would like to try out a weather visualization application, you can start a free trial of Sferic Maps by clicking the link below. We have a complete Tropical Storm layer section to help keep you informed.

Learn more

How Hurricanes Are Classified

In the United States, we classify hurricanes on the Saffir–Simpson hurricane wind scale (SSHWS). This scale measures hurricane wind-speeds to rank intensity. There are five different levels of the SSHWS. These levels range from Category 1 to Category 5. Category 5 is the most intense.

These classifications can provide some indication of the potential damage and flooding a hurricane will cause upon landfall.

The SSHWS is used only to describe hurricanes forming n the Atlantic Ocean and the northern Pacific Ocean. Other areas use different scales to label cyclones and typhoons.

While Category 5 storms are more intense than Category 4 storms, the National Weather Service indicates that both have catastrophic results.


How to Prepare for Hurricanes

The best advice when preparing for hurricanes is to prepare before tropical storm force winds begin blowing in your area. Acting ahead of time ensures you have time to prepare your home, business, family, and coworkers. Before a hurricane hits, a lot of people don’t know what to do. Some of the time, people believe that the storm won’t be “that bad.” Never underestimate the power of Mother Nature. The National Weather Service only issues these warnings and watches when they are necessary.

Here’s a business checklist for hurricane preparedness. This list also includes a good disaster preparedness kit for families as well.