Hurricanes are powerful and dangerous storms that form over tropical waters and can strike land areas in their path with deadly force. Hurricanes bring with them extremely high, sustained winds above 119 kilometers (74 miles) per hour and possibly reaching upwards of 257 kilometers (160 miles) per hour. Other destructive effects of hurricanes include storm surges, which can inundate coastlines; inland flooding from heavy rainfall; and tornadoes spawned by the ferocity of the storm. The longer that hurricanes remain over land can amplify these destructive effects, but typically only to a limited extent.
Landfall Signals Death Knell
Although there are extremely rare exceptions, landfall equals the ultimate demise of hurricanes. Hurricanes weaken over land because they are fueled by evaporation from warm ocean water, which dry land surfaces cannot provide. After only a few hours over land, hurricanes begin rapidly to deteriorate, with wind speeds decreasing significantly. If they remain over land long enough, they are eventually absorbed into other weather systems or dissipate entirely.
Size of Land Mass
The amount of time it takes a hurricane to travel over land depends partially on the size of the landmass involved. For instance, hurricanes appear to race through small island groups, such as the Cayman or Virgin Islands, with extreme swiftness, simply because the islands don’t encompass a great deal of land. And hurricanes tend to track across Florida relatively quickly, also, since it is a peninsula surrounded by water on three sides. In contrast, because of the extensiveness of the North American continent, hurricanes on northward tracks striking the central Gulf Coast spend a longer period of time over land. Additionally, hurricanes can strike multiple land areas -- particularly islands or peninsulas, such as the Bahamas, Florida and the Outer Banks -- and regain strength again over the ocean after each brief encounter with land.
Another major factor influencing how long a hurricane will remain over land is its forward speed. This is not to be confused with its wind speed, but instead is the speed at which the entire storm system as a whole travels. Forward speeds of hurricanes generally average from 18 to 39 kilometers (about 11 to 24 miles) per hour, with the fastest-moving storms occurring at the highest latitudes. Thus, hurricanes impacting New England, for instance, tend to move more quickly than hurricanes striking Cuba. However, it is possible for a hurricane to remain stationary for a period of time, as did Hurricane Mitch over Honduras in 1998.
All told, the amount of time it takes a hurricane to travel over land can vary from multiple days to mere hours. Depending on myriad meteorological factors, certain hurricanes may barely move over land or even stall entirely; Hurricane Mitch sat over Honduras for nearly a week, causing catastrophic loss of life. Hurricanes also may combine with non-tropical weather systems, such as fronts or troughs of low pressure, producing drenching rains for an extended period of time, as did Hurricane Agnes in the Mid-Atlantic in 1972. Some hurricanes never make landfall entirely, merely skirting coastlines so that their eyewall remains entirely at sea. Depending on the girth, distance from land and intensity of such storms, coastal land areas may experience anything from light rain bands and higher-than-normal tides to damaging floods and intense storm surges. And hurricanes don’t necessarily travel over land at all. Many never make landfall, completing their entire life cycle -- from formation to dissolution -- over the open ocean, such as powerful Hurricane Linda in the Eastern Pacific in 1997.