Storm enthusiasts facing disappointing early end to 2015 season
General overview 18th September 2015
GRACE is still hanging on by the skin of its teeth. This is now an elongated area of low pressure that extends from the eastern Gulf of Mexico across the Florida peninsula and onto the Outer Banks of North Carolina. Most of the associated thunderstorms are concentrated well east of Florida and the risk of development in the Gulf of Mexico has ended. There is still a slight chance it could become a tropical or subtropical depression or fish storm east of Florida over the next few days but in any event will fade to an extratropical low-pressure system as it moves north east into the Atlantic.
Tropical depression nine is located about 850 miles north-nor'east of the Amazon delta and is moving toward the north-nor'west at a leisurely 5 knots with maximum sustained winds of just over 25 knots, little more than a strong breeze really. After a burst of convection overnight, shear and dry air appear to be getting the best of the depression, with no deep convection remaining near the low-level centre. If deep convection does not return, the depression could be declared a remnant low by tonight.
Disturbance forty three is mid-Atlantic now and slightly north of the beaten storm track and moving west-nor'west at 6 knots. This system has decent organisation and some meaty thunderstorms and squalls associated with it, with a good chance of development over the next week as it moves toward the west-nor'west over the eastern Atlantic, where it will only interest fish and sailors.
We passed the mathematical mid-season on the 10th September, thus would theoretically expect the second half of the season to mirror the first, but a significantly higher than normal El Nino is piling upper-level wind shear over the Caribbean as is a very strong jet stream over the northern Gulf of Mexico. Between the two, if nothing seizes an opportunity in the next few weeks, this may pull the shutters down on the windstorm season well in advance of normal closing time for all points west of the Leeward Islands. There are still some keen pressure systems springing up in the east and central Atlantic, which always provide an outside chance of a visit to the eastern seaboard, but even the keenest catastrophists are looking despondent. Yes, even including the mad Canadian guy.