Path of Tropical Storm Helene, spaghetti models

According to the National Hurricane Center, a series of tropical storm warnings and advisories are in effect for parts of Florida's Gulf Coast on Wednesday as Tropical Storm Helene continues to strengthen.

The NHC said in its 7 a.m. CDT warning Wednesday that Helene is currently located about 60 miles east-northeast of Cozumel, Mexico, with maximum sustained winds of about 70 mph. The storm is moving northwest at about 9 mph, the NHC said, and that motion should continue through Wednesday morning.

A “general northerly motion” is expected sometime Wednesday and will continue through Friday, the hurricane center said. The center of the storm is expected to pass near the northeastern coast of the Yucatan Peninsula Wednesday morning, move across the eastern Gulf of Mexico late Wednesday and Thursday, and reach Florida's Big Bend coast late Thursday.

The NHC expects Helene to strengthen into a hurricane on Wednesday and from there “rapidly strengthen” over the eastern Gulf of Mexico, becoming a major hurricane on Thursday.

Helene’s aggressive prognosis: Helene’s explosive forecast is one of the “most aggressive” in hurricane history

Helene’s forecast is one of the “most aggressive” in hurricane history

The forecast of rapid intensification of Helene from a potential tropical cyclone to a Category 3 hurricane appears to be the fastest development the National Hurricane Center has ever predicted for a low pressure system.

“They had never forecast a major hurricane within 60 hours for a sub-tropical storm disturbance,” Sam Lillo, a meteorologist and software engineer at DTN Weather, told USA TODAY on Tuesday, based on a computer analysis of the center's historical forecast data. “The entire forecast is also basically faster than you've ever seen for 36 hours and 48 hours after a tropical depression.”

The National Hurricane Center did not have those statistics on hand Tuesday because it was focusing on the operational weather forecast for Helene, now a tropical storm, but “it's either the highest or one of the highest,” said John Cangialosi, one of the center's senior hurricane specialists.

The prediction of a “70 knot increase in wind speed within 72 hours on Monday” is one of the most aggressive forecasts for a possible tropical cyclone, Cangialosi said.

“This is an aggressive forecast for good reason,” he said. “We are trying to get ahead of the potential rapid intensification before it reaches Florida.”

Watch and warnings apply to Florida

Here's a look at the watches and warnings in effect in Florida.

Tracker for Tropical Storm Helene

Spaghetti models of tropical storm Helene

The figures show a range of forecasting tools and models, and not all are the same. The Hurricane Center uses only the four or five best performing models for its forecasts.

NHC tracks two more tropical waves in the Atlantic

The hurricane center also announced Wednesday morning that it was tracking two more tropical waves in the Atlantic, one of which could develop into a tropical depression in the coming days.

The disturbance is currently located west of the Cape Verde Islands and continues to produce “disorganized rain and thunderstorm activity,” according to the NHC.

Environmental conditions appear favorable for gradual development of the system, and “a tropical depression is likely to form within a few days” as the wave moves westward to north-northwestward across the eastern and central tropical Atlantic, the NHC said. The system has an 80 percent chance of forming within the next seven days.

The second wave is currently described as a “non-tropical low pressure area” located several hundred miles northeast of Bermuda.

According to the hurricane center, early satellite data indicated that the system was generating storm-force winds and that environmental conditions “could favor subtropical or tropical development over the next few days” as the system moved eastward and remained over the open waters of the central subtropical Atlantic.

The NHC gives this system a 20 percent chance of forming over the next seven days.

Storm tracker for the Atlantic

Gabe Hauari is a national trending news reporter for USA TODAY. You can follow him on X. @GabeHauari or email him at [email protected].

Dinah Voyles Pulver covers climate change and the environment for USA TODAY. She has covered hurricanes, tornadoes and severe weather for more than 30 years. Reach her at [email protected] or @dinahvp.