Frontal activity starting to head south for the winter
Thursday 20th October 2016
Disturbance forty six is still lounging around off the swampy coastal lowlands of eastern Nicaragua, held in place by still air aloft. Pressure gradients are starting to change and it is likely this is going to drift ashore over the next day or so without development. In the meantime, heavy rain will continue to spread across this part of central America.
Disturbance forty four is now about 600 miles southwest of Bermuda, remaining disorganised as it moves to the north-nor'west at 8 knots. There is still some chatter amongst the weather watching community of this developing into a subtropical or tropical depression, perhaps even a weak storm over the next day or two, but I can't see that at the moment. Irrespective of the degree of development, this is still expected to pass well clear of the eastern seaboard with only an outside chance of reaching the east coast of Canada.
Disturbance forty five is now about 1500 miles east of the Windward Islands. Although still moving west at 12 knots, it is becoming clearer that this will curve towards the north soon and pass well to the northeast of the Lesser Antilles early next week. This may yet develop. Jury still out.
Habitually, I disregard anyone offering guarantees of certainty at this stage, but have noticed over the past couple of days that frontal activity across the continental United States has started to head south for the winter. This will bring strong upper level wind shear across the Gulf of Mexico and is usually the first sign of the season drawing to a close. We will see.