If you are renting a villa in Sept in the VI make sure that there is local representation-- on island!! -- the onsite response time and ability is very important at this time of year.
The house must have hurricane shutters and someone to make sure they are installed and all exterior preparations like removing deck furniture, potted plants, awnings,etc. must be done well ahead of a storm and would certainly impact your trip - the house should have a generator as the power may be out for longer periods than usual - you should definitely have trip insurance that includes/defines what is covered should you have to evacuate early or even have to change your plans hours or days ahead of departure - I would not suggest you stay through a major hurricane or even a direct hit by a minor one - there have been some reports here of the experiences of forumites during a brush with OMAR last Oct. and I hope some of those posters would chime in here to add their thoughts - even with the threat of a storm coming most islanders will prepare their personal residences 1st and many businesses are closed immediately as the owners are busy with their own preparations - with all the satellite weather there is ample warning these days so just being aware while you are on island can relieve a lot of stress and combat the early rumors that will abound when there is a storm anywhere in the Atlantic.
Of course the beaches will be deserted and beautiful that time of year - some restaurants and businesses are closed for vacation but there are enough open to live like a local quite comfortably - the rates on villas must be very reasonable - available flights are likely discounted and not crowded and you will certainly be heartily welcomed everywhere during the slowest time of the year here.

exit zero,
Nice response!
To add, most villas (not all) will ask you to vacate the property if we are to get a direct hit. You can relocate to a hotel or vacate the island.
DEFINITELY get travel insurance! This way no one looses out with the loss of the financial part of it. I suppose that the percentage of an actual hit is pretty low, but we never know. We will still prepare for the most part, if we are anywhere within the cone and it might look like a miss. Better to be safe than sorry! 😮
As mentioned above, everyone will be very happy to have you here and it will be a very quiet time. Enjoy!

Is August and September months the better chance of having a major storm? Should we choose a different month? Our travel is flexible and other then a Disney trip this year we can travel at anytime. I just don't do well in HIGH humidity due to a medical reason. So any low humidity month would be good. Any suggestion? Thanks in advance as we cant cant to come back again....

Well if you want to play the odds...

Storms for the last 60 years and the weeks they came to visit and how strong they were.

We have been in Late July and Late September and both were great trips

Insurance in advised, but you will more than make up for the expense on the deals to be had.

Enjoy!

Here is a link to seasonal averages: http://www.wunderground.com/NORMS/DisplayNORMS.asp?AirportCode=TIST&SafeCityName=Saint_Thomas&StateCode=VI&Units=none&IATA=JSJ

There isn't much variation in temperature , but you will see the rainier months. I couldn't find anything specifically on humidity, but it is probably higher in the rainy months. In the tropics it is consistently fairly humid, but one doesn't feel it due to the prevailing tradewinds.

Thanks so much for all the information. I'm still a little torn on when will be the best time to visit. I guess I better get going on trying to figure this out. Plus I have a decision on which villa we want.

Be here BEFORE July 1st and after November 30th

Well, it wont be before July 1st. due to our son graduating and November 30th I will be in Walt Disney world so it will definitely be I'm assuming after January 2nd.

This year is an El nino year, our chances are less for a hurricane this year! There is always a chance, but come on. I would not discourage some one from coming down. The odds are small.
OK, stay up there and get hit with a Tornado! At least we have a fare warning!

We don't get tornado's in northern Michigan but I will never say it wouldn't happen the way the weather is these days. Actually, If I find the right villa and the air price is right I'm so there. I will drop everything and hop a plane. I'm just having a hard time with some villa reports. So I might have to research them some more and that could take me a little while. Your right at least with hurricanes you do get some advance notice and that is good but knowing me like I do and like adventure I probably would stay it out. lol