Good morning! Wow, have things changed in the tropical Atlantic Ocean since we passed August 20. Why August 20 you might ask? This date is typically the date where tropical activity begins to spike in the Atlantic basin, a spike that lasts through September and (in a season like this one is expected to be) into October. This morning, we have two active tropical cyclones, a large tropical wave moving off the west coast of Africa, and at least 2 or 3 new waves building across equatorial Africa. It promises to be very busy in the coming days!
Hurricane Danielle
Danielle is now a strong category 2 hurricane, with wind back to 105 mph -- the strongest it has been during its history. Over the last few hours though, the convection has died down on satellite imagery, and Danielle may be feeling the effects of some stronger wind shear on its northern side -- which may be allowing drier air to become entrained in the cyclone (similar to a couple of days ago). Danielle is now being tugged northwest by a trough of low pressure to its north, but it will move back underneath a high later today and could turn back toward the WNW before ultimately curving away from the United States.
Danielle may bring tropical storm conditions (at least) to Bermuda this weekend as well as high seas to the east coast. It won't affect our weather (if anything, it will actually help bring drier weather to the area as it forces sinking air on its western side into south Florida after the weekend). I don't see why Danielle won't be picked up by the east coast trough and carried out to sea. I should note, though, that there is a little more spread in our models this morning -- with a few allowing Danielle to linger off the east coast most of next week as the trough leaves it behind. Right now, I think this is very unlikely.
Tropical Storm Earl
Earl is located about 3100 miles from SWFL this morning in the eastern Atlantic. Likely feeling the effects of sinking air on the eastern side of Danielle plus the upwelling of cooler water from below by Danielle, Earl is unlikely to develop nearly as fast as Danielle did. Earl is also starting at a farther south latitude than Danielle, so a more westerly track for a longer period of time is likely. Earl is forecast to become a hurricane in a couple of days; I think the models may be too fast to do this because of the close proximity of Danielle.
Down the line, most of our models hint that Earl will follow a similar (but slightly more westerly) path compared to Danielle. A couple of points, though: if the break in the high pressure over the western Atlantic fills in behind Danielle -- Earl would have a chance to come back even more to the west. Also, a weaker Earl would feel the northward tug of Danielle less, allowing it to track more westerly. The bottom line with Earl is that, unlike Danielle, its path definitively away from SWFL is not a "done deal." Earl is worth watching over the next few days.
African Wave Train
A strong tropical wave has moved off the west coast of Africa today and may slowly develop (or become dominant compared to Earl) as it moves westward. A couple of our models put this wave in the Caribbean over Labor Day weekend while others squash it and don't develop it. There are also several other waves headed west across Africa, all worth watching as they approach the Atlantic
Brian
