I'm late in posting tonight. Anyway this is the CV part of the disco..
http://www.independentwx.com/discussion
What may soon become the main story in the tropics is the tropical wave exiting Africa this evening. Every global model, with the exception of NOGAPS, is very bullish on this system. The GFS has consistently depicted development for several days, and the latest runs are not backing off. Additionally, the CMC, UKMET, and ECMWF have become equally as aggressive over the last 24 hours. Based soley on the model consensus, it is not a question of if there will be development, but when the first advisories will be issued. Several models, most notably the GFS and UKMET, continue to show tropical cyclone formation almost immediately once the low level center enters the Atlantic. One must question if such immediate formation is realistic regardless of how favorable conditions in the eastern Atlantic may be. By day 6 and beyond, all of the aforementioned models show a significant hurricane due east of the Virgin Islands.
The synoptic setup in the eastern Atlantic does appear favorable for significant development. The Saharan Air Layer near the African coast is retreating northward along with much of the additional dry air or subsidence. the mid-level easterly jet to the south of the wave axis is very strong, and that is often a good indicator of a favorable upper air environment. The easterly flow south of the Cape Verde Islands is even a bit too strong at the moment, but the global model guidance shows those winds relaxing with time. All track guidance also keeps the wave in question well south of the 26ºC isotherm, thus making sea surface temperatures warm enough and favorable for development. We should know if all of this is hogwash or not very soon as we should begin to see signs of actual development within 72 hours at the latest. The three day mark even accounts for the possibility that the models may be developing this wave too rapidly. By Day 7, there's good reason to believe a significant hurricane will be looming in the central Atlantic.
Once the wave begins to strengthen, the evergrowing question will become where is it headed? For the next week or so, the GFS will likely provide interests between Texas and the Canadian Maritimes with a lot of entertainment as each 6 hourly model update shifts 2,000 miles give or take a few. The GFS simply cannot forecast whether the United States will be directly impacted by this storm just yet. It's not only the tropical cyclone that it will have a hard time forecasting, but also the entire global pattern that will be responsible for steering the storm in the first place. The GFS Ensembles are not immune to medium range errors either. Furthermore, even though the ECMWF is looked upon as the superior medium range model, it too often has trouble forecasting tropical cyclones with any high degree of skill beyond 5-6 days. A lot can happen. I only have two general ideas that I think are most probable. The best scenario is recurvature near 60ºW before a trough over the central Atlantic lifts out. Unfortunately, if that trough lifts out too early, then the ridge over the southeast United States and the Azores Ridge will merge. The potential hurricane would then bend westward toward the Bahamas, Florida, and Gulf of Mexico. The third scenario is an East Coast Carolinas landfall, but the ridge over the southeast should block any storm from recurving into that region. But even that cannot be ruled out at this time, because it is based on the assumption that the synoptic pattern provided by the models is at least halfway accurate.
With that said, the more immediate concern is what threat the northeast Caribbean could be facing within 6-10 days. I'm sure interests in the northeast Caribbean that keep up with the models will be looking for a yes/no answer soon as each model update makes them a bit more uneasy. There's no definite answer even for that region this evening. But now is not yet the time to become increasingly alarmed or concerned. There's still no tropical cyclone on the maps, and any storm is still 6+ days away. The 18Z GFS and 12Z ECMWF have trended closer to the Caribbean, but that is a trend that will have to be given another look over the next couple days. Until then, this is the perfect time to re-evaluate your hurricane preparedness plan.