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Information about Hurricanes

Hurricanes are extremely powerful storms that threaten the Southeast coast of the United States. Hurricane season is June 1 - November 30. During this time each year, these powerful storms that originate off the coast of Africa, in the Gulf of Mexico and the Carribean follow warm ocean currents and sometimes make landfall. The Gulf Stream, a warm current that flows northward parallel to the Southeast coast of the US, often leads the storms onto the coast. The states in the Southern US that border the Atlantic ocean and Gulf of Mexico are most often effected by these hurricanes. These states include: Texas, Louisiana, Mississippi, Alabama, Florida, Georgia, South Carolina, North Carolina, and Virginia. Since coastal regions are densely populated, especially during summer vacation when hurricanes are the greatest threat, it is very important that the paths of these powerful storms are tracked and forecast. This ensures that when landfall becomes a possibility, people know to evacuate the coast and travel inland to safety. The tracking and forecasting of these storms is an extremely important job performed by meteorologists. For more information about hurricanes, click here.

Hurricane Tracking Tools

There are many tools used by meteorologists to track hurricanes. Radar, Satellite Imagery, reports from weather buoys, and observations taken by airplane are all useful tools used in determining the size, location, and magnitude of hurricanes.

Radar stands for Radio Detection And Ranging. It works by sending out a radio wave in a circular path. Part of the signal bounces back to the radar when it hits raindrops. By knowing where on the circular path the raindrops are being hit and how fast the signal is traveling, the location of the rain can be determined.

Satellites are man made devices that are launched into space and used to monitor the earth. Weather satellites are used to take pictures of the atmosphere from above. These satellite images are useful for determining the location and size of storms.

Weather observations are taken from many different locations in the ocean by buoys. These floats are placed in the ocean to make measurements of atmospheric pressure, air and sea temperature, wind speed, and wind direction as they drift along in ocean currents. The measurements listed on buoy reports are important in accessing the strength and location of hurricanes.

Airplane observations are also used when gathering information about hurricanes. The airplanes actually fly directly into the eye of hurricanes. Once inside the hurricane, weather reconnaissance aircraft report several types of observations such as the exact location of the hurricane, and sea level pressure.

Using Map Skills to Track Hurricanes

In addition to the tools used above, hurricanes can also be tracked by simply using a map and map reading skills. The position of the hurricane is made available to the public and can be found in newspapers, on the Internet, and on television. With this information available, the hurricane track can be plotted on a map by the latitude and longitude coordinates.

Latitude and Longitude

Latitude and Longitude lines are imaginary lines on the earth that are used to measure locations on the globe. These lines are measured in degrees, minutes, and seconds. Lines of Latitude, also called parallels, run horizontally on the globe, north and south of the Equator. The Equator is latitude zero, and the North and South Poles lie at 90 degrees North and 90 degrees South. Lines of Longitude, also called meridians, run vertically on the globe, east and west of the Prime Meridian. The Prime Meridian is longitude zero, and the longitude of other locations are referenced by whether they are east or west of the Prime Meridian. Often, rather than spelling out North, South, East and West, coordinates for locations north of the equator and east of the prime meridian are shown as positive, and coordinates for locations south of the equator and west of the prime meridian are shown as negative. When coordinates are given as a pair, the first number is the latitude, and the second number is the longitude. For example, 14.6, - 46.2 is 14.6 degrees north latitude, and 46.2 degrees west longitude.

Activity

Below is a table of coordinates from Hurricane Floyd (September 7-17, 1999) that made landfall in North Carolina. Track the coordinates on the hurricane tracking chart provided by NOAA.

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