When a hurricane makes landfall, much of the attention often focuses on its intensity—the strength of the storm itself. However, the forward speed, or how fast or slow the storm is moving, can be equally important in determining the overall impact of the storm on a region.
Dr. Gilford, a climate scientist, highlights the significance of this aspect by citing Hurricane Harvey as a prime example. In 2017, Hurricane Harvey stalled over Houston, moving at a sluggish pace of just 7 mph, and unleashed record-breaking rainfall.
The extensive exposure to the storm's rains resulted in severe inland flooding that devastated the region. Similarly, Hurricane Ian moved at only 9 mph when it struck, and Hurricane Dorian, a Category 5 hurricane, was nearly stationary over the Bahamas for almost two days.
The forward speed of a hurricane can influence various impacts, from rainfall to wind damage. Dr. Gilford notes that there is ongoing research into how storm steering patterns and pressure systems might evolve in the future.
Although a study has found that hurricanes have slowed down by about 10 percent since 1949, it remains uncertain whether this trend is directly attributable to climate change.
It is plausible that the changing climate could affect the winds that steer hurricanes, potentially causing them to move more slowly.
A slower-moving storm means that a community is exposed to its effects for a longer period. This extended duration can lead to higher rainfall totals and more wind damage. However, the relationship between forward speed and storm surge is more nuanced.
Dr. Gilford explains that a larger storm generally produces a greater storm surge threat, as does a stronger storm compared to a weaker one.
Additionally, the angle at which a storm approaches the coast can significantly affect storm surge levels; storms approaching perpendicular to the shore typically generate higher surges than those approaching parallel.
In conclusion, while hurricane intensity is a critical factor, it's essential to consider all aspects of a storm, including its forward speed.
Understanding the complete picture can help communities better prepare for and respond to these potentially devastating events.