TD 12 has formed across the far eastern Atlantic, approximately 400 miles south-southwest of the Cape Verde Islands. This storm is moving to the west around 15 mph, and will make a slight turn to the west-northwest later today or tonight. The storm is in an environment with very little shear (on the order of 4-8 knots), warm sea surface temperatures (around 80F), and very little dry air or dust to the north. As this storm continues to move off to the west or just due north or west, it will develop in Tropical Storm Katia later today or tonight.
The environment will remain conducive for development over the next five days, and it will likely become a hurricane by sometime Thursday. The track of soon to be Katia beyond this weekend is uncertain. Everything depends on the strength and placement of the Bermuda high. There is one trough over the US east coast now, and this will move out over the Atlantic and then lift northward by the middle of this week. So this trough will not really be of concern as far as the track of TD 12 goes.
However, what is interesting is that the EURO breaks off a piece of this upper-level trough and sends it southward towards Bermuda. The GFS has a similar solution as well. Once this piece of the shortwave trough interacts with the convection near and to the southwest of Bermuda, the EURO has this forming into some sort of a tropical disturbance. The GFS is not quite as gung ho about this, but it does try to form at least a weak area of low pressure.
While my first reaction would be to think that this is unlikely due to the shear that will be associated with the shortwave trough as it breaks off, I am forced to take into consideration what just happened to Tropical Storm Jose. Jose formed in basically the same area with upwards of 45-50 knots of shear! So while this shear will likely limit some formation, it is not to say that something can’t form. If something does form, it will likely just move northward and have minimal impacts with land. It could, however, bring some rain to parts of Atlantic Canada. The NHC does not have this area hatched for any possible development, but this is something that bears watching.
Now lets get back to TD 12. Currently, both the EURO and GFS are showing TD 12 cutting up across the central Atlantic towards Bermuda by the middle of next week. This is because both models are showing troughs moving across the eastern US, thus weakening the Bermuda high and drawing the storm more northward. This far out, the models handle timing of troughs (especially those that have not even formed) terribly, so anything is possible. I will have updates on this storm as necessary.
Finally, one last thing I want to talk about. Deep tropical moisture will move into the southern and southwest Gulf of Mexico over the next couple of days. This area of deep moisture may help to create an organized tropical system later this week. Quick development will be possible across the southwest Gulf of Mexico between this Wednesday and this coming weekend. This will be something to keep a close eye on. I will have updates on this as well if something looks like it will form in the Gulf of Mexico.