Exploring Weather Maps

Name: _________________________________       Date: _____________

Thunderstorms are violent disturbances in the atmosphere that involve rapid changes in air pressure. They often form in low-pressure areas where there is a large amount of rising air. This usually occurs where two large masses of air meet each other along boundaries known as weather fronts.

What are today's weather conditions like? In this activity, you will look at real-time current weather data to find out if today's conditions are right for storm formation anywhere in the continental United States.

1. To begin, look at a satellite view of current United States weather. Based on the satellite view of today's cloud cover, which parts of the country might get unsettled weather today?
   
   
   
   
2. Next, you'll take a look at where the areas of low pressure are today. Go to the surface weather page and click the link for Surface Temperature With Sea Level Pressure. You can animate the map by clicking the "animate" button. Use colored pencils to sketch the map of the United States showing isobars, or lines of equal pressure. Include the pressure reading numbers, given in millibars. You should also include the areas marked highs ("H") or lows ("L").
   
   
   
   
   
   
   
   
   
   
   
3. Looking at your answers to the first two questions, describe the relationship between today's unsettled weather and areas of high or low pressure.
   
   
   
   
4. Storms often occur along weather fronts. What is the definition of a front?
   
   
   
   
5. Violent storms are often associated with cold fronts, as shown in the illustration on the page. Use colored pencils and arrows to sketch the way air moves along a cold front.
   
   
   
   
   
   
   
6. Visit the Weather Channel to see a map showing today's fronts. Cold fronts are lines with rows of small triangles. Unsettled weather can also occur along warm fronts, shown as lines with rows of small semi-circles. Use colored pencils to add today's fronts to your map for question 2.
   
   
7. How does the location of the fronts relate to your answer to question 1?
   
   
   
   
8. Based on your observations of today's weather maps, predict three cities (not your own!) in the United States that are likely having unsettled weather today.
   
   
   
   
9. Return to Weather Underground. in the search box in the upper left corner of this page, enter the names of each of the three cities you chose for the previous question. Find out how today's weather actually is in those cities. How accurate were your predictions for each of the cities?