In practice, virtually nobody can tell where a Tropical Storm/Named Storm is exactly going outside of 2 days or about 48 hours (+/-). If you look at the Probable Path projections of the NHC/NWS for more than 48 hours you will see a cone of probability that widens to over 500nm. Which means in the eastern Caribbean
the storms could hit anywhere from Grenada to Antigua
. But when you get down to 48 hours and less the the cone of probable path tightens to a couple hundred miles. What with big storms being a hundred miles wide, you now have a reasonably good idea if you are "in play" to get some nasty stuff.
- - It takes about 12 to 14 hours to motor-sail to Trinidad from Grenada which is enough time to "get out of Dodge" if the storm is likely to cross over the area. I was in Grenada for Hurricane
Ivan and would never stay there if threatened with that situation again. So thereafter during August to November, I kept my boat
ready to move/depart in a hour or less. One year we got down to 42 hours before the storm hooked a right turn and went north. But we had already packed everything away and got the lines shortened down.
- - I use the word "motor-sail" as within 48 hours or less the huge effects of the low pressure system will negate the trade
winds and actually cause winds to come from the west. The old folklore in the eastern islands is that if the winds die to nothing or reverse it is time to head
for the high ground, something big is coming.
- - Basically, there is only one raw source (not counting the French for the French Islands) of weather data in this hemispheric area and it is the NWS/NOAA and their satellites. You can and do have internet
access to all the basic data in chart and photo
versions and can use them to either agree with the NWS/NHC forecasts or disagree.
- - Having been in the meteorology business for over 55 years I can heartily recommend Steve Dashew's "Mariners Weather Handbook." It is quite thick, and if you can successfully get through it you will have a very good knowledge base on weather as it can affect cruising. See: SetSail » Blog Archive » Mariners Weather Handbook: A Guide to Forecasting & Tactics
I have it on CDrom as the actual book is very thick and heavy.
- - The guys back in Miami
sitting in a concrete building with no windows really don't have the level of vested interest you have sitting on your boat
bobbing in the bays of the eastern Caribbean
. Any and all sources of weather information are valuable in helping you to visualize and decide what to do. So, IMHO, learning
how to read and interpret the weather charts and photos puts you in "command" of your future and the safety
of your boat and crew. Which is what long term cruising
is all about.