The Atlantic has sprung to life, and there's a lot to cover today. The primary topic and only threat to land is Hurricane Helene in the eastern Gulf of Mexico. Then there's newly-formed Tropical Storm Isaac in the north-central Atlantic, and possibly future-Joyce east of the Lesser Antilles.
The map below shows the Thursday 11am EDT advisory for Hurricane Helene from the National Hurricane Center, with the amazing spread of hurricane and tropical storm warnings covering a wide swath and penetrating far inland.
Helene has not rapidly intensified yet as was feared, but is a powerful Category 2 hurricane that should continue to intensify in the remaining hours before landfall on Thursday evening. It is abnormally large, and tropical storm winds extend as far as 345 miles to the east of the center as of Thursday morning. The Thursday morning set of Hurricane Threats and Impacts (HTI) graphics are included here for reference, but you can always find the most current version with interactive maps at https://www.weather.gov/srh/tropical#hti. I overlaid the "cone of uncertainty" to illustrate that the cone is not (and never was) meant for showing where impacts will be experienced. In fact, the vast majority of impacts shown are outside of the cone!
The storm will be traveling rather quickly tonight as it makes landfall, and that will allow hurricane-force winds to reach far inland, much more so than usual -- notice how far inland those hurricane warnings extend on the NHC forecast map. On top of being a strong hurricane, the large size will help it generate extremely high storm surges in the Big Bend area of Florida.
Remember you can find a long, updating radar loop of Helene as it approaches the coast and moves inland at https://bmcnoldy.earth.miami.edu/tropics/radar/
Next, Isaac is a small storm that had a somewhat complicated evolution... it's been "on our radar" for several days, but clearly lacked tropical characteristics, until Wednesday night when it was named. It's way up at 37N and headed east, so not a threat to land yet, but could reach the Azores by the end of the weekend. The NHC forecast brings this up to hurricane intensity this weekend, which would make it the 6th hurricane of the season so far.
This the 9th named storm of the season, and Isaac is still a name from the original set of six lists, first appearing in 1982 and every six years since then. However, the 1982 and 1994 seasons never reached the "I" storm, so this year is only its 6th time being used.
Then, the easterly wave I've been mentioning for several days is very close to becoming a tropical depression or tropical storm. It's centered about 1600 miles east of the Lesser Antilles and is forecast by models to strengthen in the coming days. However, models also indicate it will turn north way before reaching the Lesser Antilles, so it should not be a threat to land. The next name on the list is Joyce.
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