Tropical Cyclone Nine—soon to be Tropical Storm Helene—is gradually forming between the east coast of Nicaragua and western Cuba over the southwest Caribbean Sea. This is a bad location for Florida, and as my last tropical update on Sept. 10 indicated, late September and October are climatologically the worst times for the west coast of Florida.

I expect Helene to rapidly intensify into a major hurricane (winds of 111 mph and higher) before it makes landfall on Florida’s west coast—probably on Thursday, north of Tampa. Warnings will likely be issued on much of the west coast for tropical storm- or hurricane-force winds, associated storm surge and flooding rain.

This will be another large storm in areal extent, and again, it could well be in the category 3 or 4 range when it strikes.

Helene is forming at a time when a La Niña is also forming, resulting in low wind shear. Plus, sea surface temperatures in the Gulf of Mexico are at record highs– moist, mid-level conditions are in place. All of this is rocket fuel for hurricanes. 

As far as Helene's effects on the Suncoast area, I expect a long period—24 hours or more—of gale-force winds, 5 or more inches of rain, and storm surges after the eye passes some distance offshore Wednesday. After that happens, onshore winds will create storm surge on all the keys from Sarasota and Manatee counties northward. 

High tides are about the highest of the year during early fall. In Sarasota, high tide on Thursday morning is at 7:01 a.m., and on Friday morning at 8:42 a.m.

With more than three days to go before Helene's impacts begin, there is still some uncertainty about where the storm's eye will be when it crosses the coast. A small deviation in landfall could make a big difference in local impacts. 

Also, a reminder that the storm's cone is the likely path of the eye. It's very important to remember that the effects from this storm will be well outside of the cone—and can produce very serious, life-threatening damage. This is why you must stay alert and up to date

While this hurricane season has produced less named storms than expected, every one has hit land—and two unnamed storms also made landfall and created record amounts of rain. 

While the 2024 season is more than half over, this second half looks like a thriller. The 2024 season has had mostly Gulf storms this year—the unnamed storm on June 11, and storms Alberto, Beryl, Chris, Debbie and Francine roaring ashore on the Gulf Coast. Helene will likely become the fifth hurricane and second major hurricane of the season, and this will be the fourth time four hurricanes have struck the U.S. in a single hurricane season since 2000. (The maximum number of hurricanes to hit the U.S. in one year was six. Human health is being impacted by these repeated storms; the Climate Adaptation Center (CAC) will be talking about that at the upcoming Florida Climate Conference in November. Please join us.

The CAC has been forecasting a big year for local impacts—and we've already had a lot! We must be very careful to prepare for Helene's impacts now, then adjust as the storm takes shape in the next few days.