Hurricanes are the atmosphere’s biggest show of force and energy, and Hurricane Ian is no exception. Forecasters are particularly worried about Ian’s potential impacts on the west coast of Florida and for good reason.
Florida, despite sticking out like a sore thumb into the tropical Atlantic, has lucked out at missing most major hurricanes in recent decades but that may be about to change. Hurricane Ian is expected to strike somewhere along the west-central coast of Florida late Wednesday as a borderline category 3 or 4 hurricane, what we consider a major hurricane.
While the wind may be the thing most of us find jaw-dropping, the biggest force of destruction and damage tends to come from flooding. Unlike a regular storm system, that flooding doesn’t just come from lots of rain. In the case of a tropical system we have to talk about storm surge; literally the wall or swelling of water ahead of an eye that then makes landfall ahead of the storm’s center.
In the case of Hurricane Ian, forecasters are predicting an 8- to 12-foot surge of water from about Fort Myers to just south of Tampa.
When you combine the storm surge with rainfall totals over 20 inches, you can envision a picture of catastrophic flooding up and down the Florida coastline.
Based on the topography, we can predict how deep the water in various areas will be. Here’s a look at a few spots along the west-central coast of Florida. Areas in red represent the potential for more than 9 feet of water covering the ground, orange is 6-9 feet and yellow is 3-6 feet.
Fort Myers, Florida:
Port Charlotte, Florida:
In the first map of the forecast track at the beginning of this article, it’s important to pay attention to the cone of uncertainty. That’s the blue/gray shaded area that encompasses the other possible tracks/paths for the center and worst conditions from Ian. You can get a further idea of this by looking at what forecasters call spaghetti plots:
These are the possible scenarios from numerous computer model forecasts. You can see, there’s quite a degree of uncertainty still in the forecast track for Hurricane Ian and every few miles can make a big difference. That’s because the worst conditions hug the eye wall of a hurricane, including the strongest winds and highest storm surge just north and east of it.
As of midday, Ian’s wind radius looked like this as it left Cuba.
When you look at the entire path of the wind over time, we can see the maximum sustained wind gust swath follows the northeast side of the storm, and the European model is predicting extremely high winds.
Again, the storm surge and flooding rain combination can be catastrophic, but some areas will also be battered by wind gusting over 100 mph. On Monday, some of the models slowed down Ian or even stalled it near Tampa. Luckily the latest model runs don't show that, but it remains a possibility worth monitoring. The slowed or stalled hurricane would be a total catastrophe as it would prolong the storm surge, rain and high winds.
The climate change angle on hurricanes
While our warming climate isn’t necessarily creating more hurricanes, it is making them stronger and more capable of rapid intensification.
Hurricanes only develop over warm ocean water. Their primary fuel source is the incredible amount of energy stored in water vapor over water that is at least 85 degrees. Ocean water, like the rest of the globe, have warmed. But it’s estimated 70% of the heating of our planet so far has been absorbed by our oceans. That’s a staggering amount of energy.
The extra-energized oceans help tropical storms and hurricanes quickly intensify. There’s been a noticeable increase in more intense cyclones over recent decades.
Major hurricanes, defined as category 3 or larger that intensify rapidly cause billions in damage every year.