Suggestion that the current southward jet stream dip just to the east of Florida will pick up Erika or its remnants and steer them in the direction of the North Atlantic towards the end of next week - to boost the wind and rain we currently have!

http://www.weather.com/storms/hurricane/news/tropical-storm-hurricane-erika-atlantic-august-2015

Perhaps - but there is growing concern that a ridge may build to the north of Erika before it has a chance to follow that path. The ECM 00z operational showed such an evolution, which resulted in a major hurricane wandering about just east of Florida days 8-10.

The uncertainty with this will have implications for our own weather beyond a week's range I expect.

GFS 6z showing a major tropical storm heading into he North Atlantic well into FFI, i.e. around the 10 Sept. It probably won't happen quite like that, and Erika would have to go a couple of times round Florida to arrive that late, but it is an indication that the Atlantic hurricane season is finally coming to life.

It's due to a ridge building north of Erika and causing steering currents to collapse in its vicinity. The storm wanders about for a number of days before being drawn NW by a trough.

Believe it or not, I can see a good chance of a Hurricane Sandy type event, with the storm moving NW into the U.S.

After all, ECM's been hinting at it for a couple of days now, ahead of the other models, and it led the way with Sandy in 2012.

The thing is, the storm is currently behaving erratically in the NE Caribbean, making its presence east of Florida highly uncertain in the first place - give it until the weekend, and the picture ought to be a lot clearer.

Some sad news from Dominica this evening, for as many as 20 people have perished in flash floods caused by Erika's torrential rains Couple that with extensive property damage and there's already a strong case building for the name 'Erika' to be retired post-season. 

I can't see what it is that the Americans are panicking about..

News links to storm centre of facebook say winds of 50mph with gusts as high as 65mph..

lol

Just a typical Atlantic storm for us.

Okay i guess there will be a lot of rainfall but then again I've been to Florida and their storm drains are massive!  

It will probably turn out to be a Super Storm, with a weather reporter standing in a puddle holding his hat on, whilst bracing the gusts.Shouting into a big furry microphone.

They got it bad in Dominica though.

To be fair Dominica has very high mountains to catch the rain... Florida is pretty much flat.

TS Fred forming very close to the coast of Africa and expected to become a hurricane even as it reaches the Cape Verde Islands - speculation that these islands have never before had a hurricane warning.

http://www.weather.com/storms/hurricane/news/tropical-storm-fred-atlantic-2015 

Fred is then forecast to head WNW so substantial energy due to be injected into the Atlantic circulation

Fred has now become a hurricane and is affecting the Cape Verde Islands. A hurricane has never formed this far east in the Atlantic since satellite data became available. It is thought the Cape Verde Islands might have been hit by a hurricane back in 1892.

http://www.bbc.co.uk/news/world-africa-34107755

Believe it or not... Fred is still alive and kicking, and having been so unkind to the Cape Verde islands, may go on to give the Azores Islands a rough time too:

There does seem to be a tendency for ex-hurricanes moving into the sub-tropics to prove resilient against high wind shear the likes of which Fred has been dealing with. Perhaps it's to do with the increasing spin imparted by the Earth, which a well defined circulation can take advantage of, this also increasing the low-level convergence and helping the system to fire off deep convection.

With SSTs of just over 27*C to the SW of the Azores (unusually high), and wind shear falling lower, there's a risk that Fred could gain strength significantly before reaching the islands. To do this, though, the system would need to still be well organised, which recent global model runs have not been keen on.

One to keep an eye on then, as landfalls as a tropical cyclone on both the CV islands and the Azores islands would be another highly unusual (perhaps unprecedented in the last 100 years or so?) achievement to add to Fred's name. 

Elsewhere in the Atlantic, a vigorous tropical wave is moving south of the CV islands and showing signs of development into a tropical depression. That's how things usually go down there, as opposed to a wave rapidly organising into a storm and then hurricane and walloping the CV islands!

Been watching this thing for 6 days

http://www.wunderground.com/hurricane/atlantic/2015/tropical-depression-Ida?map=history

In that time, it hasn't intensified at all; has only moved 9 degrees west and 7 degrees north. Currently it is actually moving slightly eastward! Given that this thing has been alive for 6 days already, and will hardly move in the next 6 days, assuming it then intensifies and follows a normal course into the gulf of mexico before moving eastward after newfoundland that could be an extra 10 days which is getting pretty close to the record for longest lived cyclone.

Thoughts?

Forecast changed :(

Wind sheer increased, humidity declined. I'm really hoping it can hang on though, it just seems to have no will to survive. 

Been going now for 8 days (already longer than any other storm this season). If it survives and doesn't break up (as the GEM predicts) then it could last at least another 10 days which brings us to 18 days. 

ECM once had this turning into a hybrid cyclone similar to Sandy of 2012 (but not hitting the U.S.)

Funnily enough we had a long-term wanderer that year as well I think. I remember it persisting near the Azores for ages, at one point spawning a 'twin' that raced NE to bring some wind and rain to our shores.

Most Atlantic tropical cyclones tend to recurve before reaching the likes of the Gulf of Mexico. Those that don't tend to be the ones we end up hearing about.

Visits to the Caribbean are more common, but news from there often seems to have to be bigger to make it to the UK via the news outlets.

That would be Nadine. I recall there was a nasty storm that was popularly referred to as "Child of Nadine".

Thanks for that Nouska  That storm had me hooked for a while, watching it wander the North Atlantic with varying intensity, at one point temporarily losing tropical status only to gain it back again a day or so later.

Back to the present (not as exciting as Back to the Future), and Ida is barely 'alive' now, so to speak. There's only a few traces of deep convection and a weak swirl with top sustained winds of 25 mph... very few tropical cyclones retain their name for long once their winds have fallen that light. Yet believe it or not, many models keep Ida as an identifiable cyclone for another 5 or 6 days, but this assumes that it holds together in the face of high wind shear associated with a frontal boundary to its north.

The 'hybrid' solutions from ECM seemed to have Ida strong enough at this point in time to in some way use baroclinic forcing associated with the frontal system to intensify. That would have been fascinating to watch unfold... seems unlikely to happen with Ida in its current condition though!

It seems Ida was unable to hold on in the end.

Instead we now have tropical storm Joaquin to watch.

This is a storm experiencing a fair bit of wind shear but also benefiting from great ventilation aloft. It's that process which Ida could have used to become a hybrid storm had it not been hammered down so much prior to meeting this environment.

GFS turns Joaquin into an ex-tropical storm (merging with a frontal boundary) before passing close to the U.S., which given the presence of very warm waters could allow for some hybrid characteristics. However, UKMO keeps the storm tropical right up until it engages with the mid-latitude westerlies many days from now.

With so much uncertainty, this storm is giving the NOAA a real headache!

Two points: 

1) Does a mod/admin want to rename this thread to Atlantic hurricane season and sticky it?

2) Those GFS charts showing warm core, cold core are awesome. Where did you get them?

You'll get the cyclone phase diagrams here...

http://moe.met.fsu.edu/cyclonephase/

Click on the model you want and full globe map then opens to allow you to click on specific systems.

In response to point number one by Q, I reckon the best thing to do is merge this with the existing tropical thread