Hurricane Hermine – upgraded from a tropical storm on Thursday afternoon – has taken aim at Florida’s western Big Bend area, and should strike late Thursday night or early Friday morning.
It will be the first full-fledged hurricane to hit Florida since 2005. That’s an astonishingly long run for the southeasternmost US state. Expected to make landfall as a category one storm, Hermine doesn’t carry quite the same risks as a larger storm, which the Washington Post reports could cost the state as much as $200 billion.
But Hermine is still a plenty powerful storm in its own right. The NOAA warning reports gusts as high as 75 miles per hour, with hurricane-force winds extending 45 miles from its center and tropical storm-force winds as far as 185 miles from its center.
It’s still unknown precisely how Hermine will behave after striking Florida.
The most consistent model has shown that Hermine could move up the East Coast and spend several days fairly immobile off the coast of New Jersey and New York.
— Eric Holthaus (@EricHolthaus) September 1, 2016
That would likely be bad news for those areas. When storms sit in on place, centered offshore, they can kick up larger and larger storm surges and high tides with their winds. That’s a big part of what made Hurricane Sandy so devastating. At the same time, the NOAA does not anticipate that Hermine will retain its hurricane force at that point.
But that’s still a bit too far in the future to predict confidently.
Hurricanes and tropical storms are notoriously difficult to predict, though computer models have improved drastically in the last decade. Unlike broad patterns of warmth and cooling in the atmosphere, tropical storms can shift, shrink, or grow because of tiny events that models aren’t very good at understanding.
NOAA hurricane specialist James Franklin told Business Insider that beyond three days out, hurricane models live in a kind of “fantasy land.”
It’s normal for models to look a bit chaotic that far in the future.
Thomas Downs, a meteorologist with Weatherbell Analytics, told Business Insider that some particular weather events in the middle latitudes are making Hermine especially difficult to precisely predict.
“What I see as a meteorologist is that the computer model’s very confused right now,” he said. “When there are shifts [from one run of a model to another] like this, we know something funky is going to happen because of the different, strange tracks.”
Right now, there’s an atmospheric “trough” over the Carolinas. Hermine could smack into it, intermingle, and move over land as a weaker storm that moves quickly and dissipates – more like a typical winter storm than a cyclone.
Or it could shunt out to sea, where warm water would likely help the storm maintain its power.
“Does that mean it’s going to hit Washington, DC, or New York or Boston?” Downs said. “This storm especially is one that has a mind of its own. The science of meteorology hasn’t really caught up to quite the way hurricanes intensify and interact. And that’s quite frankly why we’re seeing this right now.”
Follow along with Business Insider for updates on Hermine.