How's the Weather? Tips for Reading Weather Maps

Most folks will evaluate weather conditions by taking a peek out the window or turning on the television for a temperature reading, but weather maps rarely come into the picture. However, learning to read a weather map or two can be fascinating stuff when you realize that all of those dots, squiggles and patterns of color running across the chart actually mean something significant. Meteorologists use a variety of charts to keep the public abreast of current weather conditions and what they can expect in the future.

The first step in familiarizing yourself with the weather outside is to understand the different types of weather charts that are available. Different maps will be used by different groups for a variety of purposes. For example, aviation weather maps will offer much more information about cloud formations, wind direction and visibility, since they can greatly affect a flight. Other maps will track storms forming in the ocean, or weather patterns that evolve as they move across mountain ranges. Two of the most common types of maps that are used include live weather maps and satellite charts.

Live Weather Maps
Live weather maps are created by weather radar that is referred to as Doppler radar by many television stations. Doppler radar is also used by numerous airports to assess conditions for the planes flying in and out. However, the largest system of weather radar is the National Weather Service Next Generation Weather Radars, or NEXRAD. Radar images are formed when energy beams are sent out into the atmosphere. When they return, the amount of beam left is measured in terms of size and how long it took to return. Types of objects that reflect the beam include different forms of precipitation like sleet, snow or rain.

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Live weather maps are not an exact science, however. Objects like mountains and trees can sometimes skew the images on the maps, making you think that there is no precipitation in an area where it is currently snowing. The radar images follow a color code that will determine how intense the precipitation is. In addition to precipitation, live weather maps can also detect when wind direction changes and when there might be rotation that could indicate conditions are ripe for a tornado. The National Weather Service can issue a tornado warning for an area based on this information.

Satellite Weather Maps
Meteorologists can utilize the satellites orbiting high above the earth for viewing cloud formations over land and sea. This type of weather map can be particularly helpful in tracking large storms across the ocean, like those that come fast and furious during hurricane season. By watching a storm while it is still far from shore, meteorologists can give plenty of advanced warning for a big storm, allowing residents to make necessary preparations or evacuate the area. In addition to pictures, satellites can also use radiometers to measure the amount of infrared radiation of the clouds. This helps meteorologists to know how low and how big clouds are, which will give them a more accurate weather analysis of the current conditions. Understanding Meteorology

Weather maps have been used for decades by those who are fascinated in what the future holds in terms of temperatures and precipitation. As technology increases, so does the ability of weather maps to more accurately pinpoint weather conditions in a given area and predict what the weather will be a day or a week in the future.

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