Eye of the Storm

Activity Source: 

A tropical storm is brewing in the Atlantic Ocean. It’s causing rain and thunderstorms over the Caribbean, and it will soon be a tropical depression — the beginning of a hurricane. By the time Hurricane Mitch leaves the Central America, more than 11,000 people will be dead and as many as 18,000 more will be missing. (Activity adapted from Mapping Our World at http://edcommunity.esri.com/MOW.)


  • Computer with Internet connection.


  1. To find Map 1 online, go to http:// esriurl.com/2014ESW1. Click the “Details”button and select “Contents” (middle button). Turn on Precipitation layer.
  2. The annual precipitation appears on the map, but you cannot determine the average precipitation for each country. You must adjust the transparency of the precipitation layer to view each country’s average precipitation data.
  3. Hover over the Precipitation layer, click on the right arrow that appears and click on Transparency. Drag the slider over to 50%. Click off of the slider and the country lines appear lightly through the Precipitation layer. In each country, click on each area of precipitation to see how many millimeters of rainfall there was in that area.
  4. Estimate and record the annual precipitation for five countries of your choice. Be sure to include country name.
  5. Now, close Map 1 and open Map 2 online at http://esriurl.com/2014ESW2. Click the “Details” button and select “Contents” (middle button). Turn on “Pre-Hurricane Mitch” and “Mitch2.” Click the name “Pre Hurricane Mitch” and “Mitch 2” to expand the legend.
  6. Both of these layers show the locations of the eye of the storm at different time points. For locations when Mitch was a hurricane, the legend indicates Mitch’s category.
  7. Click on the most southeastern dark square representing Tropical Storm Mitch. A window displays time and wind velocity in miles per hour, and pressure (PR) in millibars, among other things. The time is in the format month/day/hour (24-hour clock); the Z stands for Zulu time. When was Tropical Storm Mitch at this location? What was Mitch’s wind speed at this location?
  8. Once Hurricane Mitch made landfall, the winds weakened and Mitch downgraded to a tropical storm. Nonetheless, in the days that followed, Mitch poured more than 30 inches of rain!
  9. Turn off all layers except “Mitch3 Satellite Image,” “Central America,” and “Continents.” Turn on the “Rain3” layer. The rain pattern is overlaid on top of Mitch 3 Satellite Image. Zoom and pan to position map so you can see the entire satellite imagery along with the rain pattern. What pattern do you notice in the amount of rainfall? Is this a pattern you expected to find? Why or why not?
  10. Turn remaining rain and satellite layers on and off as needed to answer these questions: What is the highest range of rainfall in the Rain4 layer? Which country received the majority of this heavy rain?