Various forecast guidance continues to point to gradual tropical development somewhere in the Caribbean during the first and second week of November. It looks like to me that based on analysis of current conditions that this possible development may come from a tropical disturbance now located over the eastern Atlantic near about 30 to 35 West Longitude. Before I get into the various forecast guidance details, I want to point out that environmental conditions are forecast to begin becoming more favorable for development across the eastern Caribbean around Friday with the central and eastern Caribbean possibly being favorable for tropical development by this coming weekend.
The GFS model guidance shows a broad low pressure system forming over the central Caribbean by early next week that never really spins up into a tropical cyclone. The GFS ensemble guidance is different than its operational guidance counterpart in that it forecasts a broad low pressure system forming near Jamaica around November 7th which spins up into a tropical cyclone near the Cayman Islands on November 12th that starts to track towards the Yucatan Peninsula and western Cuba by November 13th.
The Canadian model guidance is considered suspect this morning and I'm not using it in my forecast for potential tropical development. It forecasts two tropical cyclones to form. The first one is forecast to develop right over the Virgin Islands on Friday that takes off to the northeast into the open Atlantic. The Canadian model guidance then forecasts a second tropical cyclone developing just south of Jamaica on November 5th that tracks right over the Cayman Islands by November 6th and towards the Yucatan Peninsula and western Cuba by November 7th.
The NAVGEM model guidance clearly hones in on the tropical disturbance now near 30-35 West Longitude as a definite candidate for tropical development. It forecasts this tropical disturbance to track near Barbados and the Windward Islands on Friday bringing squally weather to these islands. The NAVGEM model guidance then forecasts this tropical disturbance to develop into a broad low pressure system that looks to start to spin up into a tropical cyclone just south of Jamaica by about November 5th.
The European model guidance forecasts that low pressure will form just south of Jamaica around November 3rd that appears to originate from that tropical disturbance near 30-35 West Longitude. The European model guidance forecasts that this low pressure system will remain over the southwestern Caribbean through at least November 7th, but the European model never really shows it spinning up into a tropical cyclone.
The FIM model guidance, which has been very consistent in forecasting development, shows a broad low pressure system forming over the central or eastern Caribbean this coming weekend that eventually spins up into a tropical cyclone near the Mona Passage between Hispaniola and Puerto Rico around November 6th that gradually tracks towards and into the southeastern Bahamas by about November 9th and for it to stall over the southeastern Bahamas as a hurricane through at least November 11th.
So, here are my thoughts: During late October and the first half of November, the western Caribbean is normally the spot to look at for potential tropical cyclone development. Additionally, anything that does develop in the western Caribbean normally tracks northeastward across Cuba, Hispaniola, Puerto Rico or the Virgin Islands.
I do think there is a pretty good chance that we will see a tropical cyclone develop somewhere over the Caribbean either next week or at the very latest the following week. The reason why I think that we will see tropical development is that the Madden Julian Oscillation is in a favorable upward motion phase. I do think that the tropical disturbance now near 30-35 West Longitude will be the system to watch closely as it heads into the Caribbean between Friday and Sunday with the most likely time for development between November 5th and November 12th. I do think that pretty much the entire Caribbean will be in play in regards to this potential development as guidance points to favorable environmental conditions spreading westward across the Caribbean this weekend into next week.
So, at this point I would frankly be surprised if nothing develops in the Caribbean during the first two weeks of November based on the forecast favorable environmental conditions and the upward motion pulse of the Madden Julian Oscillation. So, this is something that I will be monitoring closely, especially once we get into next week and the following week. Until then, tropical development is highly unlikely from today through at least Sunday across the Atlantic, Gulf of Mexico and the Caribbean.
Rob Lightbown
Crown Weather Services
http://www.crownweather.com