What are a Hurricane's Characteristics?Hurricane Intensity |
The hurricane strength or hurricane intensity can either be measured based on the central pressure or the maximum sustained wind speed. The wind speed is most commonly used to describe the intensity of a hurricane. The Saffir-Simpson Scale is a "hurricane potential damage scale" [1] based on maximum sustained (one-minute) wind speeds. The Saffir-Simpson Scale has five categories. Category 1 hurricanes have winds of 74 to 95 mph, while Category 5 hurricanes have winds of 155 mph or greater [1],[2].
Hurricane Tracks and Forward Speed
Due to the shape (and length) of the Texas coastline, there is no typical path that hurricanes take when they make landfall in Texas. As shown in the figure, there is a slight tendency for storms to be moving in a northerly or northwesterly direction at landfall. Corpus Christi provides a good example of this since many of the storms that have affected this area moved from south to north or from southeast to northeast.
The forward speed (or translation speed) of hurricanes can also be highly variable. On average these storms are moving at ~16 km/h (10 mph) at landfall. However, some storms move very slowly or stall, while others move very quickly. The forward speed of the storm is determined by upper level steering winds and interaction between the tropical cyclone and mid-latitude systems.
The forward speed (or translation speed) of hurricanes can also be highly variable. On average these storms are moving at ~16 km/h (10 mph) at landfall. However, some storms move very slowly or stall, while others move very quickly. The forward speed of the storm is determined by upper level steering winds and interaction between the tropical cyclone and mid-latitude systems.
The figure shows distribution of daily hurricane direction of movement (a) and Histogram of hurricane translation speed for all hurricanes that influenced Texas between 1950-2009 (b).
Acknowledgements & Credits: Click here for literature cited in this section, "What's a Hurricane?" This material is based upon work supported by the Texas Department of Public Safety's Division of Emergency Management. Background photo courtesy of Mark Moran (Creative Commons license CC BY 2.0). Forward speed figure by Zhu and Quiring (2016).
© 2019 Jennifer L. Irish & Steven M. Quiring. All rights reserved.
© 2019 Jennifer L. Irish & Steven M. Quiring. All rights reserved.