Hurricane Season begins mid-May in the warm Pacific and early June in the warm waters of the Atlantic. In most years, the peak time for hurricanes in the Caribbean, Gulf of Mexico and Atlantic regions is September and lasts until November. Historically, September 10th is the day that most frequently sees an Atlantic hurricane. Hurricane season in the Pacific peaks earlier than in the Atlantic and wanes by late September.

Atlantic-, Gulf of Mexico- and Caribbean- spawned hurricanes can come ashore anywhere from the Gulf Coast of Texas to Florida, the Bahamas and the East Coast from Florida to New England. Hurricanes and Tropical Storms occasionally hit portions of eastern Canada.

Hurricanes that form in the western Pacific are called typhoons or cyclones, and frequently hit Japan and Korea. Eastern Pacific storms that form off the west coast of Mexico will sometimes curve north into Mexico and rarely hit Hawaii. Occasionally, the remnants of a storm will move into the southwest U.S. Most eastern Pacific hurricanes never make landfall.

Tropical storm and hurricane formation can occur when a "wave" of energy moves over warm tropical waters (above 80^oF or 27^oC). This wave, or small disturbance can create enough instability to cause an area of thunderstorms accompanied by falling barometric pressure. The pressure drops due to the continual rising motion from the thunderstorms.

Once the pressure falls enough the Coriollis force will cause a full counter-clockwise circulation to develop. The Coriollis Force is the turning of winds caused by the rotation of the Earth on its axis. As the Earth rotates, it creates a force that causes the wind to deflect or curve. The winds "curve" to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

This circulation will then work to strengthen the low pressure area if conditions are right. Weak winds aloft allow thunderstorm complexes to build over the circulation center. The rising motion in these storms can continue to lower the pressure and draw more warm, moist air toward the center, which feeds the storms -- and the cycle continues.

Once the circulating low pressure area deepens enough so the pressure difference across the system is high, winds will be strong enough to classify the storm as a tropical storm. As long as the upper level conditions and sea surface temperatures remain favorable, the storm could strengthen to become a hurricane.

Hurricanes are categorized using the Saffir-Simpson Scale, which rates hurricanes from 1- 5 according to wind speed. The fastest winds are located around the "eye" of the storm.

During a hurricane, water is built up in the quadrant to the upper right of the direction of movement. Winds, which are the most intense in this area, pile the water up into a wall or dome. This water-wall is called the storm surge. As the surge approaches land, where the sea floor is higher, the wall or dome of water will grow in height. A powerful hurricane can push a storm surge over 18 feet or 5.5 meters high onto the shore. NOAA hosts a web page about storm surge . Most deaths from tropical storms or hurricanes are caused by storm surge.

Hurricane prediction has improved greatly, yet it is still difficult to make accurate forecasts more than 3-4 days from landfall. Some meteorologists spend their entire careers studying these magnificent storms.

Hurricanes are named so the National Weather Service and the public can keep storms straight without knowing their exact locations. Hurricane names are planned six years in advance. There is a separate list for storms that form in the Pacific and Atlantic. The names alternate between male and female names that are common in the countries affected by the storms. This year's list will be used again in 2009. The number of storms fluctuates from year to year.

One weather event that is known to have an effect on hurricane generation is El Nino. During and El Nino event, the number of Atlantic hurricanes is historically reduced. During La Nina, the number of hurricanes is normal or above normal. That said, even these patterns do not always occur as predicted during hurricane season.

NOAA's Hurricane Center has information on present hurricanes and an archive of past hurricanes. You will also find important information regarding safety during and preparation for hurricanes. And there are hurricane tracking charts so that you too can be a hurricane tracker from the safety of your home or school.

More great links to Hurricane Information:

The National Hurricane Center, Hurricane Awareness for Kids

The Canadian Hurricane Centre, Just for Kids

Review the Water Cycle:

1. Energy from Sun changes water to water vapor.
2. Water vapor rises. It cools and condenses to form clouds.
3. Winds blow the clouds over land.
4. Clouds meet cool air, and rain or snow falls to the ground.
5. Most of the water returns to large lakes and oceans.

Materials Needed:

• Glass jar
• Rubber band
• Plastic wrap

Next, demonstrate the water cycle.

1. Fill a large, glass bottle or jar half full of water.
2. Cover the top of the jar with plastic wrap and secure the plastic wrap in place with a rubber band.
3. Place the jar in a sunny window.
4. Observe for a few hours.

What happens? Why did it happen?

Answer: Water drops form on the underside of the plastic wrap. Energy from the sun turned the water into water vapor (evaporation), which caused water drops to form (condense) on the plastic wrap.

More to Think About:

• How can you speed up the process of evaporation and condensation?
• How does the Water Cycle help to explain a hurricane?

What is the rush of water preceding a hurricane called?

1. Funeral dirge
2. Tidal surge
3. Storm surge
4. Vacuum purge

The "Select Schools" program is a fundamental part of WeatherNet for schools. The program selects "model" WeatherNet schools for their expertise and familiarity with the program to serve as a resource for other WeatherNet schools or schools interested in joining WeatherNet. Many times, prospective schools ask to speak with a school in their area that is using the program. WeatherNet Select Schools agree to talk with these schools and possibly host a visit to "show off" just what WeatherNet means to their students, teachers and the community.

Select Schools are rewarded for their support with product upgrades, promotion as a community resource, priority access to new products and offerings and $25.00 to $250.00 gift certificates that can be used for classroom supplies, etc., for every referral that is completed.

We are looking for schools to add to the program. If you would like to have your school considered for inclusion in the WeatherNet Select Schools program, contact Diana at 800-544-4429 x 112 or email me at ddell@aws.com.

The Select Schools program is one of many WeatherNet activities to keep schools in touch with each other as well as with the support team here at WeatherNet. I hope to hear from you soon.

While most hurricanes occur between June 1 and November 30 in the Atlantic and between May 15 and November 30 in the Pacific, there is an organization whose job is to monitor activity in the tropics all year round. This organization is known as the Tropical Prediction Center (TPC). The TPC works with the Canadian Hurricane Centre and other national organizations around the world to closely watch and forecast tropical cyclone activity.

The National Hurricane Center (NHC), a branch of the TPC, watches the oceans during "hurricane season". Their job is to prepare and issue forecasts, watches and warnings for the United States and 24 other countries in the Americas, Caribbean and for the waters of the North Atlantic Ocean, Caribbean Sea, Gulf of Mexico and the eastern North Pacific Ocean. During the "off season" the NHC conducts educational programs to teach people to prepare for and address damage caused by hurricanes.

The Canadian Hurricane Centre (CHC) gathers information on tropical storms in the Atlantic and assesses their potential impact on Canadian territory. They report on activity in the areas along the Canada -- United States border and into Canadian waters to 200 nautical miles. On average, three or four tropical storm systems affect Canada each year and are closely monitored by the center. When they are not following tropical systems, the meteorologists from the CHC are also deeply involved in educating the Canadian public about the preventative measures for and affects of hurricanes. The two centers often work closely together to ensure the safety of the public in both countries.