How to Read a Typhoon Track Map? A Complete Guide to Track Points, Forecast Lines, and Wind Circles
On a typhoon track map, the color of the dots indicates intensity, solid lines show the past track, dashed lines show the forecast track, and concentric circles represent wind circles. Master these elements to assess typhoons on your own.
Basic Elements of a Track Map
When you open the real-time track map on TyphoonSays, you will see the following elements:
1. Track Points (Colored Dots)
Each dot represents the center position of the typhoon at a specific time, with colors indicating the intensity level at that moment:
| Color | Intensity Level |
|---|---|
| Blue-Green | Tropical Depression |
| Yellow | Tropical Storm |
| Orange-Yellow | Severe Tropical Storm |
| Orange-Red | Typhoon |
| Red | Severe Typhoon |
| Dark Red/Purple | Super Typhoon |
Clicking on any track point reveals detailed data for that moment: latitude/longitude, central pressure, maximum wind speed, movement direction, and speed.
2. Solid and Dashed Lines
- Solid Line: The actual path the typhoon has already traveled.
- Dashed Line: The future path forecasted by meteorological agencies, with each forecast point marked with the estimated time of arrival.
3. Wind Circles (Concentric Circles)
Irregular circles centered on the typhoon's eye, indicating the range of influence for different wind forces:
- Grade 7 Wind Circle: Area with wind speeds ≥ Grade 7; entering this zone means experiencing noticeable strong winds.
- Grade 10 Wind Circle: Area with wind speeds ≥ Grade 10; damaging gales.
- Grade 12 Wind Circle: Area with wind speeds ≥ Grade 12; destructive hurricane-force winds.
Note that the radii of the wind circles are often unequal across the four quadrants (Northeast, Southeast, Southwest, Northwest), as asymmetric typhoon structures are common.
Three-Step Practical Assessment Method
- Check Distance: Use the distance measurement tool to determine the shortest distance between your city and the typhoon center or its forecast path. Combine this with the wind circle radii to judge whether you will enter the high-wind zone.
- Check Trends: Refresh the forecast several times. Is the track stable? Are forecasts from multiple agencies converging?
- Check Intensity Changes: Are the track point colors deepening (intensifying) or fading (weakening)? The intensity near landfall is the key factor.
A Common Misconception
The typhoon center not passing over your location ≠ No impact. A typhoon is a system hundreds of kilometers in diameter. The impact range of spiral rainbands, outer gales, and storm surges extends far beyond the central track. To assess impacts, look at the wind circles and rainfall forecasts, not just the track line.