How to Understand a Hurricane Forecast

Hurricanes occur all over the world throughout the year. The United States has a 6-month “hurricane season” that initially starts in June and ends in November. If you have never heard an actual hurricane forecast, then you may not be familiar with the typical terms used. It is of the highest importance to have the knowledge to understand what is being forecasted. The following are the most common terms used in hurricane forecasts.

Difficulty: Easy

Instructions

1. Advisory
   
   This official information provides details on all watches and warnings that are in effect for tropical cyclones.

2. Best Track
   
   It is a hurricane track that has been estimated using recent data.

3. Center
   
   It is the middle (core) of a tropical storm.

4. Eye
   
   This is the calm center area of a storm. A wall cloud will frame it (at least part way).

5. Eye Wall or Wall Cloud
   
   Either word is used to describe the area of clouds adjacent to the eye of the storm.

6. Hurricane or Typhoon
   
   It will depend on your location to the International Dateline, as to which word you use. They both are a warm centered tropical storm with a sustained surface wind that is 74 mph or more.

7. Hurricane Warning
   
   It is a forecast provided to an area when sustained winds of at least 74 mph (hurricane conditions) are expected within the next 24 hours.

8. Hurricane Watch
   
   It is a forecast provided to a specific region when hurricane conditions are expected within 36 hours.

9. Landfall
   
   It is the point where the middle of a tropical cyclone meets with land.

10. Present Movement
    
    It is the calculated movement of the middle of a system.

11. Storm Surge
    
    It is the rare rise in the sea levels associated with a storm.

12. Tropical Cyclone
    
    It is a low-pressure, non-frontal, warm-centered system with a clear surface circulation and is located above tropical or sub tropical waters.

13. Tropical Depression
    
    It is a tropical cyclone with a surface wind speed not above 38 mph.

14. Tropical Disturbance
    
    It is a large organized system formed over the tropical or sub tropical waters, which has held for 24 hours or longer.

15. Tropical Storm
    
    It is an organized system of thunderstorms with distinct surface rotation and wind speed from 39 to 73 mph.

Tips & Warnings

• Advisories are given by tropical warning centers.
• Tropical storms located in the Northern Hemisphere from the Greenwich Meridian to east of the International Dateline, are called hurricanes.
• Tropical storms located in the west of the International Dateline and north of the Equator are called typhoons.
• See resources for more information.
• When evacuation notices are given, you should leave the designated area as soon as possible.
• Even if past warnings about hurricanes were incorrect, you should still consider each hurricane warning seriously.

Resources

• National Hurricane Center

[grouch]

on 12/13/2007 This is very well written and helpful to anyone who lives or will be visiting a tropical area during the season.