New disturbance in the south western Caribbean
Thursday 10th November 2016
I was poised yesterday to sign off for the season but just before hitting the send button on my annual ‘Finished With Engines' message, I decided to go with an inexplicable hunch. Just as well.
Almost overnight, the chatterers have trained their sights on the far south-western Caribbean for a potential development around the middle of next week. This is one of the areas where I believe there is still some decent warm water and would be vulnerable if a break in the ramparts of upper level shear were to materialise. There is no tropical disturbance in the area at present, but pressure contours lines have started to shape up for a low pressure development east of Nicaragua/north of Panama early next week. This will be disturbance fifty-two from hereon. Any development here would in all likelihood track north to north east, possibly towards Haiti and the Dominican Republic but no further north. The Gulf of Mexico and, to a degree the south eastern United States would be ring-fenced by strong westerly winds aloft which seem to be in place for the winter now. Having said that, late storms don't have well-trodden paths to follow, so unexpected tracks are always possible.
The strong, wide air stream from the north coast of South America, north east into the central Atlantic is buffering westbound air from the convergence zone just east of the Windward Islands. This pile-up has caused a disturbance – fifty one to form. This is unlikely to develop due to high wind shear but has been holding position for several days now and is causing enhanced showers and thunderstorms across the Lesser Antilles. I would expect this to dissipate into a retreating front quite soon but in the meantime, will produce line squalls across the islands of the eastern Caribbean for the next day or two.